text: // Copyright 2008, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: mheule@google.com (Markus Heule)
  //
  // Google C++ Testing Framework (Google Test)
  //
  // Sometimes it's desirable to build Google Test by compiling a single file.
  // This file serves this purpose.
  
  // This line ensures that gtest.h can be compiled on its own, even
  // when it's fused.
  #include "gtest.h"
  
  // The following lines pull in the real gtest *.cc files.
  // Copyright 2005, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  //
  // The Google C++ Testing Framework (Google Test)
  
  // Copyright 2007, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  //
  // Utilities for testing Google Test itself and code that uses Google Test
  // (e.g. frameworks built on top of Google Test).
  
  #ifndef GTEST_INCLUDE_GTEST_GTEST_SPI_H_
  #define GTEST_INCLUDE_GTEST_GTEST_SPI_H_
  
  
  namespace testing {
  
  // This helper class can be used to mock out Google Test failure reporting
  // so that we can test Google Test or code that builds on Google Test.
  //
  // An object of this class appends a TestPartResult object to the
  // TestPartResultArray object given in the constructor whenever a Google Test
  // failure is reported. It can either intercept only failures that are
  // generated in the same thread that created this object or it can intercept
  // all generated failures. The scope of this mock object can be controlled with
  // the second argument to the two arguments constructor.
  class GTEST_API_ ScopedFakeTestPartResultReporter
      : public TestPartResultReporterInterface {
   public:
    // The two possible mocking modes of this object.
    enum InterceptMode {
      INTERCEPT_ONLY_CURRENT_THREAD,  // Intercepts only thread local failures.
      INTERCEPT_ALL_THREADS           // Intercepts all failures.
    };
  
    // The c'tor sets this object as the test part result reporter used
    // by Google Test.  The 'result' parameter specifies where to report the
    // results. This reporter will only catch failures generated in the current
    // thread. DEPRECATED
    explicit ScopedFakeTestPartResultReporter(TestPartResultArray* result);
  
    // Same as above, but you can choose the interception scope of this object.
    ScopedFakeTestPartResultReporter(InterceptMode intercept_mode,
                                     TestPartResultArray* result);
  
    // The d'tor restores the previous test part result reporter.
    virtual ~ScopedFakeTestPartResultReporter();
  
    // Appends the TestPartResult object to the TestPartResultArray
    // received in the constructor.
    //
    // This method is from the TestPartResultReporterInterface
    // interface.
    virtual void ReportTestPartResult(const TestPartResult& result);
   private:
    void Init();
  
    const InterceptMode intercept_mode_;
    TestPartResultReporterInterface* old_reporter_;
    TestPartResultArray* const result_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(ScopedFakeTestPartResultReporter);
  };
  
  namespace internal {
  
  // A helper class for implementing EXPECT_FATAL_FAILURE() and
  // EXPECT_NONFATAL_FAILURE().  Its destructor verifies that the given
  // TestPartResultArray contains exactly one failure that has the given
  // type and contains the given substring.  If that's not the case, a
  // non-fatal failure will be generated.
  class GTEST_API_ SingleFailureChecker {
   public:
    // The constructor remembers the arguments.
    SingleFailureChecker(const TestPartResultArray* results,
                         TestPartResult::Type type,
                         const string& substr);
    ~SingleFailureChecker();
   private:
    const TestPartResultArray* const results_;
    const TestPartResult::Type type_;
    const string substr_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(SingleFailureChecker);
  };
  
  }  // namespace internal
  
  }  // namespace testing
  
  // A set of macros for testing Google Test assertions or code that's expected
  // to generate Google Test fatal failures.  It verifies that the given
  // statement will cause exactly one fatal Google Test failure with 'substr'
  // being part of the failure message.
  //
  // There are two different versions of this macro. EXPECT_FATAL_FAILURE only
  // affects and considers failures generated in the current thread and
  // EXPECT_FATAL_FAILURE_ON_ALL_THREADS does the same but for all threads.
  //
  // The verification of the assertion is done correctly even when the statement
  // throws an exception or aborts the current function.
  //
  // Known restrictions:
  //   - 'statement' cannot reference local non-static variables or
  //     non-static members of the current object.
  //   - 'statement' cannot return a value.
  //   - You cannot stream a failure message to this macro.
  //
  // Note that even though the implementations of the following two
  // macros are much alike, we cannot refactor them to use a common
  // helper macro, due to some peculiarity in how the preprocessor
  // works.  The AcceptsMacroThatExpandsToUnprotectedComma test in
  // gtest_unittest.cc will fail to compile if we do that.
  #define EXPECT_FATAL_FAILURE(statement, substr) \
    do { \
      class GTestExpectFatalFailureHelper {\
       public:\
        static void Execute() { statement; }\
      };\
      ::testing::TestPartResultArray gtest_failures;\
      ::testing::internal::SingleFailureChecker gtest_checker(\
          &gtest_failures, ::testing::TestPartResult::kFatalFailure, (substr));\
      {\
        ::testing::ScopedFakeTestPartResultReporter gtest_reporter(\
            ::testing::ScopedFakeTestPartResultReporter:: \
            INTERCEPT_ONLY_CURRENT_THREAD, &gtest_failures);\
        GTestExpectFatalFailureHelper::Execute();\
      }\
    } while (::testing::internal::AlwaysFalse())
  
  #define EXPECT_FATAL_FAILURE_ON_ALL_THREADS(statement, substr) \
    do { \
      class GTestExpectFatalFailureHelper {\
       public:\
        static void Execute() { statement; }\
      };\
      ::testing::TestPartResultArray gtest_failures;\
      ::testing::internal::SingleFailureChecker gtest_checker(\
          &gtest_failures, ::testing::TestPartResult::kFatalFailure, (substr));\
      {\
        ::testing::ScopedFakeTestPartResultReporter gtest_reporter(\
            ::testing::ScopedFakeTestPartResultReporter:: \
            INTERCEPT_ALL_THREADS, &gtest_failures);\
        GTestExpectFatalFailureHelper::Execute();\
      }\
    } while (::testing::internal::AlwaysFalse())
  
  // A macro for testing Google Test assertions or code that's expected to
  // generate Google Test non-fatal failures.  It asserts that the given
  // statement will cause exactly one non-fatal Google Test failure with 'substr'
  // being part of the failure message.
  //
  // There are two different versions of this macro. EXPECT_NONFATAL_FAILURE only
  // affects and considers failures generated in the current thread and
  // EXPECT_NONFATAL_FAILURE_ON_ALL_THREADS does the same but for all threads.
  //
  // 'statement' is allowed to reference local variables and members of
  // the current object.
  //
  // The verification of the assertion is done correctly even when the statement
  // throws an exception or aborts the current function.
  //
  // Known restrictions:
  //   - You cannot stream a failure message to this macro.
  //
  // Note that even though the implementations of the following two
  // macros are much alike, we cannot refactor them to use a common
  // helper macro, due to some peculiarity in how the preprocessor
  // works.  If we do that, the code won't compile when the user gives
  // EXPECT_NONFATAL_FAILURE() a statement that contains a macro that
  // expands to code containing an unprotected comma.  The
  // AcceptsMacroThatExpandsToUnprotectedComma test in gtest_unittest.cc
  // catches that.
  //
  // For the same reason, we have to write
  //   if (::testing::internal::AlwaysTrue()) { statement; }
  // instead of
  //   GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement)
  // to avoid an MSVC warning on unreachable code.
  #define EXPECT_NONFATAL_FAILURE(statement, substr) \
    do {\
      ::testing::TestPartResultArray gtest_failures;\
      ::testing::internal::SingleFailureChecker gtest_checker(\
          &gtest_failures, ::testing::TestPartResult::kNonFatalFailure, \
          (substr));\
      {\
        ::testing::ScopedFakeTestPartResultReporter gtest_reporter(\
            ::testing::ScopedFakeTestPartResultReporter:: \
            INTERCEPT_ONLY_CURRENT_THREAD, &gtest_failures);\
        if (::testing::internal::AlwaysTrue()) { statement; }\
      }\
    } while (::testing::internal::AlwaysFalse())
  
  #define EXPECT_NONFATAL_FAILURE_ON_ALL_THREADS(statement, substr) \
    do {\
      ::testing::TestPartResultArray gtest_failures;\
      ::testing::internal::SingleFailureChecker gtest_checker(\
          &gtest_failures, ::testing::TestPartResult::kNonFatalFailure, \
          (substr));\
      {\
        ::testing::ScopedFakeTestPartResultReporter gtest_reporter(\
            ::testing::ScopedFakeTestPartResultReporter::INTERCEPT_ALL_THREADS, \
            &gtest_failures);\
        if (::testing::internal::AlwaysTrue()) { statement; }\
      }\
    } while (::testing::internal::AlwaysFalse())
  
  #endif  // GTEST_INCLUDE_GTEST_GTEST_SPI_H_
  
  #include <ctype.h>
  #include <math.h>
  #include <stdarg.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <time.h>
  #include <wchar.h>
  #include <wctype.h>
  
  #include <algorithm>
  #include <iomanip>
  #include <limits>
  #include <list>
  #include <map>
  #include <ostream>  // NOLINT
  #include <sstream>
  #include <vector>
  
  #if GTEST_OS_LINUX
  
  // TODO(kenton@google.com): Use autoconf to detect availability of
  // gettimeofday().
  # define GTEST_HAS_GETTIMEOFDAY_ 1
  
  # include <fcntl.h>  // NOLINT
  # include <limits.h>  // NOLINT
  # include <sched.h>  // NOLINT
  // Declares vsnprintf().  This header is not available on Windows.
  # include <strings.h>  // NOLINT
  # include <sys/mman.h>  // NOLINT
  # include <sys/time.h>  // NOLINT
  # include <unistd.h>  // NOLINT
  # include <string>
  
  #elif GTEST_OS_SYMBIAN
  # define GTEST_HAS_GETTIMEOFDAY_ 1
  # include <sys/time.h>  // NOLINT
  
  #elif GTEST_OS_ZOS
  # define GTEST_HAS_GETTIMEOFDAY_ 1
  # include <sys/time.h>  // NOLINT
  
  // On z/OS we additionally need strings.h for strcasecmp.
  # include <strings.h>  // NOLINT
  
  #elif GTEST_OS_WINDOWS_MOBILE  // We are on Windows CE.
  
  # include <windows.h>  // NOLINT
  # undef min
  
  #elif GTEST_OS_WINDOWS  // We are on Windows proper.
  
  # include <io.h>  // NOLINT
  # include <sys/timeb.h>  // NOLINT
  # include <sys/types.h>  // NOLINT
  # include <sys/stat.h>  // NOLINT
  
  # if GTEST_OS_WINDOWS_MINGW
  // MinGW has gettimeofday() but not _ftime64().
  // TODO(kenton@google.com): Use autoconf to detect availability of
  //   gettimeofday().
  // TODO(kenton@google.com): There are other ways to get the time on
  //   Windows, like GetTickCount() or GetSystemTimeAsFileTime().  MinGW
  //   supports these.  consider using them instead.
  #  define GTEST_HAS_GETTIMEOFDAY_ 1
  #  include <sys/time.h>  // NOLINT
  # endif  // GTEST_OS_WINDOWS_MINGW
  
  // cpplint thinks that the header is already included, so we want to
  // silence it.
  # include <windows.h>  // NOLINT
  # undef min
  
  #else
  
  // Assume other platforms have gettimeofday().
  // TODO(kenton@google.com): Use autoconf to detect availability of
  //   gettimeofday().
  # define GTEST_HAS_GETTIMEOFDAY_ 1
  
  // cpplint thinks that the header is already included, so we want to
  // silence it.
  # include <sys/time.h>  // NOLINT
  # include <unistd.h>  // NOLINT
  
  #endif  // GTEST_OS_LINUX
  
  #if GTEST_HAS_EXCEPTIONS
  # include <stdexcept>
  #endif
  
  #if GTEST_CAN_STREAM_RESULTS_
  # include <arpa/inet.h>  // NOLINT
  # include <netdb.h>  // NOLINT
  # include <sys/socket.h>  // NOLINT
  # include <sys/types.h>  // NOLINT
  #endif
  
  // Indicates that this translation unit is part of Google Test's
  // implementation.  It must come before gtest-internal-inl.h is
  // included, or there will be a compiler error.  This trick is to
  // prevent a user from accidentally including gtest-internal-inl.h in
  // his code.
  #define GTEST_IMPLEMENTATION_ 1
  // Copyright 2005, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  // Utility functions and classes used by the Google C++ testing framework.
  //
  // Author: wan@google.com (Zhanyong Wan)
  //
  // This file contains purely Google Test's internal implementation.  Please
  // DO NOT #INCLUDE IT IN A USER PROGRAM.
  
  #ifndef GTEST_SRC_GTEST_INTERNAL_INL_H_
  #define GTEST_SRC_GTEST_INTERNAL_INL_H_
  
  // GTEST_IMPLEMENTATION_ is defined to 1 iff the current translation unit is
  // part of Google Test's implementation; otherwise it's undefined.
  #if !GTEST_IMPLEMENTATION_
  // If this file is included from the user's code, just say no.
  # error "gtest-internal-inl.h is part of Google Test's internal implementation."
  # error "It must not be included except by Google Test itself."
  #endif  // GTEST_IMPLEMENTATION_
  
  #ifndef _WIN32_WCE
  # include <errno.h>
  #endif  // !_WIN32_WCE
  #include <stddef.h>
  #include <stdlib.h>  // For strtoll/_strtoul64/malloc/free.
  #include <string.h>  // For memmove.
  
  #include <algorithm>
  #include <string>
  #include <vector>
  
  
  #if GTEST_CAN_STREAM_RESULTS_
  # include <arpa/inet.h>  // NOLINT
  # include <netdb.h>  // NOLINT
  #endif
  
  #if GTEST_OS_WINDOWS
  # include <windows.h>  // NOLINT
  #endif  // GTEST_OS_WINDOWS
  
  
  namespace testing {
  
  // Declares the flags.
  //
  // We don't want the users to modify this flag in the code, but want
  // Google Test's own unit tests to be able to access it. Therefore we
  // declare it here as opposed to in gtest.h.
  GTEST_DECLARE_bool_(death_test_use_fork);
  
  namespace internal {
  
  // The value of GetTestTypeId() as seen from within the Google Test
  // library.  This is solely for testing GetTestTypeId().
  GTEST_API_ extern const TypeId kTestTypeIdInGoogleTest;
  
  // Names of the flags (needed for parsing Google Test flags).
  const char kAlsoRunDisabledTestsFlag[] = "also_run_disabled_tests";
  const char kBreakOnFailureFlag[] = "break_on_failure";
  const char kCatchExceptionsFlag[] = "catch_exceptions";
  const char kColorFlag[] = "color";
  const char kFilterFlag[] = "filter";
  const char kListTestsFlag[] = "list_tests";
  const char kOutputFlag[] = "output";
  const char kPrintTimeFlag[] = "print_time";
  const char kRandomSeedFlag[] = "random_seed";
  const char kRepeatFlag[] = "repeat";
  const char kShuffleFlag[] = "shuffle";
  const char kStackTraceDepthFlag[] = "stack_trace_depth";
  const char kStreamResultToFlag[] = "stream_result_to";
  const char kThrowOnFailureFlag[] = "throw_on_failure";
  const char kFlagfileFlag[] = "flagfile";
  
  // A valid random seed must be in [1, kMaxRandomSeed].
  const int kMaxRandomSeed = 99999;
  
  // g_help_flag is true iff the --help flag or an equivalent form is
  // specified on the command line.
  GTEST_API_ extern bool g_help_flag;
  
  // Returns the current time in milliseconds.
  GTEST_API_ TimeInMillis GetTimeInMillis();
  
  // Returns true iff Google Test should use colors in the output.
  GTEST_API_ bool ShouldUseColor(bool stdout_is_tty);
  
  // Formats the given time in milliseconds as seconds.
  GTEST_API_ std::string FormatTimeInMillisAsSeconds(TimeInMillis ms);
  
  // Converts the given time in milliseconds to a date string in the ISO 8601
  // format, without the timezone information.  N.B.: due to the use the
  // non-reentrant localtime() function, this function is not thread safe.  Do
  // not use it in any code that can be called from multiple threads.
  GTEST_API_ std::string FormatEpochTimeInMillisAsIso8601(TimeInMillis ms);
  
  // Parses a string for an Int32 flag, in the form of "--flag=value".
  //
  // On success, stores the value of the flag in *value, and returns
  // true.  On failure, returns false without changing *value.
  GTEST_API_ bool ParseInt32Flag(
      const char* str, const char* flag, Int32* value);
  
  // Returns a random seed in range [1, kMaxRandomSeed] based on the
  // given --gtest_random_seed flag value.
  inline int GetRandomSeedFromFlag(Int32 random_seed_flag) {
    const unsigned int raw_seed = (random_seed_flag == 0) ?
        static_cast<unsigned int>(GetTimeInMillis()) :
        static_cast<unsigned int>(random_seed_flag);
  
    // Normalizes the actual seed to range [1, kMaxRandomSeed] such that
    // it's easy to type.
    const int normalized_seed =
        static_cast<int>((raw_seed - 1U) %
                         static_cast<unsigned int>(kMaxRandomSeed)) + 1;
    return normalized_seed;
  }
  
  // Returns the first valid random seed after 'seed'.  The behavior is
  // undefined if 'seed' is invalid.  The seed after kMaxRandomSeed is
  // considered to be 1.
  inline int GetNextRandomSeed(int seed) {
    GTEST_CHECK_(1 <= seed && seed <= kMaxRandomSeed)
        << "Invalid random seed " << seed << " - must be in [1, "
        << kMaxRandomSeed << "].";
    const int next_seed = seed + 1;
    return (next_seed > kMaxRandomSeed) ? 1 : next_seed;
  }
  
  // This class saves the values of all Google Test flags in its c'tor, and
  // restores them in its d'tor.
  class GTestFlagSaver {
   public:
    // The c'tor.
    GTestFlagSaver() {
      also_run_disabled_tests_ = GTEST_FLAG(also_run_disabled_tests);
      break_on_failure_ = GTEST_FLAG(break_on_failure);
      catch_exceptions_ = GTEST_FLAG(catch_exceptions);
      color_ = GTEST_FLAG(color);
      death_test_style_ = GTEST_FLAG(death_test_style);
      death_test_use_fork_ = GTEST_FLAG(death_test_use_fork);
      filter_ = GTEST_FLAG(filter);
      internal_run_death_test_ = GTEST_FLAG(internal_run_death_test);
      list_tests_ = GTEST_FLAG(list_tests);
      output_ = GTEST_FLAG(output);
      print_time_ = GTEST_FLAG(print_time);
      random_seed_ = GTEST_FLAG(random_seed);
      repeat_ = GTEST_FLAG(repeat);
      shuffle_ = GTEST_FLAG(shuffle);
      stack_trace_depth_ = GTEST_FLAG(stack_trace_depth);
      stream_result_to_ = GTEST_FLAG(stream_result_to);
      throw_on_failure_ = GTEST_FLAG(throw_on_failure);
    }
  
    // The d'tor is not virtual.  DO NOT INHERIT FROM THIS CLASS.
    ~GTestFlagSaver() {
      GTEST_FLAG(also_run_disabled_tests) = also_run_disabled_tests_;
      GTEST_FLAG(break_on_failure) = break_on_failure_;
      GTEST_FLAG(catch_exceptions) = catch_exceptions_;
      GTEST_FLAG(color) = color_;
      GTEST_FLAG(death_test_style) = death_test_style_;
      GTEST_FLAG(death_test_use_fork) = death_test_use_fork_;
      GTEST_FLAG(filter) = filter_;
      GTEST_FLAG(internal_run_death_test) = internal_run_death_test_;
      GTEST_FLAG(list_tests) = list_tests_;
      GTEST_FLAG(output) = output_;
      GTEST_FLAG(print_time) = print_time_;
      GTEST_FLAG(random_seed) = random_seed_;
      GTEST_FLAG(repeat) = repeat_;
      GTEST_FLAG(shuffle) = shuffle_;
      GTEST_FLAG(stack_trace_depth) = stack_trace_depth_;
      GTEST_FLAG(stream_result_to) = stream_result_to_;
      GTEST_FLAG(throw_on_failure) = throw_on_failure_;
    }
  
   private:
    // Fields for saving the original values of flags.
    bool also_run_disabled_tests_;
    bool break_on_failure_;
    bool catch_exceptions_;
    std::string color_;
    std::string death_test_style_;
    bool death_test_use_fork_;
    std::string filter_;
    std::string internal_run_death_test_;
    bool list_tests_;
    std::string output_;
    bool print_time_;
    internal::Int32 random_seed_;
    internal::Int32 repeat_;
    bool shuffle_;
    internal::Int32 stack_trace_depth_;
    std::string stream_result_to_;
    bool throw_on_failure_;
  } GTEST_ATTRIBUTE_UNUSED_;
  
  // Converts a Unicode code point to a narrow string in UTF-8 encoding.
  // code_point parameter is of type UInt32 because wchar_t may not be
  // wide enough to contain a code point.
  // If the code_point is not a valid Unicode code point
  // (i.e. outside of Unicode range U+0 to U+10FFFF) it will be converted
  // to "(Invalid Unicode 0xXXXXXXXX)".
  GTEST_API_ std::string CodePointToUtf8(UInt32 code_point);
  
  // Converts a wide string to a narrow string in UTF-8 encoding.
  // The wide string is assumed to have the following encoding:
  //   UTF-16 if sizeof(wchar_t) == 2 (on Windows, Cygwin, Symbian OS)
  //   UTF-32 if sizeof(wchar_t) == 4 (on Linux)
  // Parameter str points to a null-terminated wide string.
  // Parameter num_chars may additionally limit the number
  // of wchar_t characters processed. -1 is used when the entire string
  // should be processed.
  // If the string contains code points that are not valid Unicode code points
  // (i.e. outside of Unicode range U+0 to U+10FFFF) they will be output
  // as '(Invalid Unicode 0xXXXXXXXX)'. If the string is in UTF16 encoding
  // and contains invalid UTF-16 surrogate pairs, values in those pairs
  // will be encoded as individual Unicode characters from Basic Normal Plane.
  GTEST_API_ std::string WideStringToUtf8(const wchar_t* str, int num_chars);
  
  // Reads the GTEST_SHARD_STATUS_FILE environment variable, and creates the file
  // if the variable is present. If a file already exists at this location, this
  // function will write over it. If the variable is present, but the file cannot
  // be created, prints an error and exits.
  void WriteToShardStatusFileIfNeeded();
  
  // Checks whether sharding is enabled by examining the relevant
  // environment variable values. If the variables are present,
  // but inconsistent (e.g., shard_index >= total_shards), prints
  // an error and exits. If in_subprocess_for_death_test, sharding is
  // disabled because it must only be applied to the original test
  // process. Otherwise, we could filter out death tests we intended to execute.
  GTEST_API_ bool ShouldShard(const char* total_shards_str,
                              const char* shard_index_str,
                              bool in_subprocess_for_death_test);
  
  // Parses the environment variable var as an Int32. If it is unset,
  // returns default_val. If it is not an Int32, prints an error and
  // and aborts.
  GTEST_API_ Int32 Int32FromEnvOrDie(const char* env_var, Int32 default_val);
  
  // Given the total number of shards, the shard index, and the test id,
  // returns true iff the test should be run on this shard. The test id is
  // some arbitrary but unique non-negative integer assigned to each test
  // method. Assumes that 0 <= shard_index < total_shards.
  GTEST_API_ bool ShouldRunTestOnShard(
      int total_shards, int shard_index, int test_id);
  
  // STL container utilities.
  
  // Returns the number of elements in the given container that satisfy
  // the given predicate.
  template <class Container, typename Predicate>
  inline int CountIf(const Container& c, Predicate predicate) {
    // Implemented as an explicit loop since std::count_if() in libCstd on
    // Solaris has a non-standard signature.
    int count = 0;
    for (typename Container::const_iterator it = c.begin(); it != c.end(); ++it) {
      if (predicate(*it))
        ++count;
    }
    return count;
  }
  
  // Applies a function/functor to each element in the container.
  template <class Container, typename Functor>
  void ForEach(const Container& c, Functor functor) {
    std::for_each(c.begin(), c.end(), functor);
  }
  
  // Returns the i-th element of the vector, or default_value if i is not
  // in range [0, v.size()).
  template <typename E>
  inline E GetElementOr(const std::vector<E>& v, int i, E default_value) {
    return (i < 0 || i >= static_cast<int>(v.size())) ? default_value : v[i];
  }
  
  // Performs an in-place shuffle of a range of the vector's elements.
  // 'begin' and 'end' are element indices as an STL-style range;
  // i.e. [begin, end) are shuffled, where 'end' == size() means to
  // shuffle to the end of the vector.
  template <typename E>
  void ShuffleRange(internal::Random* random, int begin, int end,
                    std::vector<E>* v) {
    const int size = static_cast<int>(v->size());
    GTEST_CHECK_(0 <= begin && begin <= size)
        << "Invalid shuffle range start " << begin << ": must be in range [0, "
        << size << "].";
    GTEST_CHECK_(begin <= end && end <= size)
        << "Invalid shuffle range finish " << end << ": must be in range ["
        << begin << ", " << size << "].";
  
    // Fisher-Yates shuffle, from
    // http://en.wikipedia.org/wiki/Fisher-Yates_shuffle
    for (int range_width = end - begin; range_width >= 2; range_width--) {
      const int last_in_range = begin + range_width - 1;
      const int selected = begin + random->Generate(range_width);
      std::swap((*v)[selected], (*v)[last_in_range]);
    }
  }
  
  // Performs an in-place shuffle of the vector's elements.
  template <typename E>
  inline void Shuffle(internal::Random* random, std::vector<E>* v) {
    ShuffleRange(random, 0, static_cast<int>(v->size()), v);
  }
  
  // A function for deleting an object.  Handy for being used as a
  // functor.
  template <typename T>
  static void Delete(T* x) {
    delete x;
  }
  
  // A predicate that checks the key of a TestProperty against a known key.
  //
  // TestPropertyKeyIs is copyable.
  class TestPropertyKeyIs {
   public:
    // Constructor.
    //
    // TestPropertyKeyIs has NO default constructor.
    explicit TestPropertyKeyIs(const std::string& key) : key_(key) {}
  
    // Returns true iff the test name of test property matches on key_.
    bool operator()(const TestProperty& test_property) const {
      return test_property.key() == key_;
    }
  
   private:
    std::string key_;
  };
  
  // Class UnitTestOptions.
  //
  // This class contains functions for processing options the user
  // specifies when running the tests.  It has only static members.
  //
  // In most cases, the user can specify an option using either an
  // environment variable or a command line flag.  E.g. you can set the
  // test filter using either GTEST_FILTER or --gtest_filter.  If both
  // the variable and the flag are present, the latter overrides the
  // former.
  class GTEST_API_ UnitTestOptions {
   public:
    // Functions for processing the gtest_output flag.
  
    // Returns the output format, or "" for normal printed output.
    static std::string GetOutputFormat();
  
    // Returns the absolute path of the requested output file, or the
    // default (test_detail.xml in the original working directory) if
    // none was explicitly specified.
    static std::string GetAbsolutePathToOutputFile();
  
    // Functions for processing the gtest_filter flag.
  
    // Returns true iff the wildcard pattern matches the string.  The
    // first ':' or '\0' character in pattern marks the end of it.
    //
    // This recursive algorithm isn't very efficient, but is clear and
    // works well enough for matching test names, which are short.
    static bool PatternMatchesString(const char *pattern, const char *str);
  
    // Returns true iff the user-specified filter matches the test case
    // name and the test name.
    static bool FilterMatchesTest(const std::string &test_case_name,
                                  const std::string &test_name);
  
  #if GTEST_OS_WINDOWS
    // Function for supporting the gtest_catch_exception flag.
  
    // Returns EXCEPTION_EXECUTE_HANDLER if Google Test should handle the
    // given SEH exception, or EXCEPTION_CONTINUE_SEARCH otherwise.
    // This function is useful as an __except condition.
    static int GTestShouldProcessSEH(DWORD exception_code);
  #endif  // GTEST_OS_WINDOWS
  
    // Returns true if "name" matches the ':' separated list of glob-style
    // filters in "filter".
    static bool MatchesFilter(const std::string& name, const char* filter);
  };
  
  // Returns the current application's name, removing directory path if that
  // is present.  Used by UnitTestOptions::GetOutputFile.
  GTEST_API_ FilePath GetCurrentExecutableName();
  
  // The role interface for getting the OS stack trace as a string.
  class OsStackTraceGetterInterface {
   public:
    OsStackTraceGetterInterface() {}
    virtual ~OsStackTraceGetterInterface() {}
  
    // Returns the current OS stack trace as an std::string.  Parameters:
    //
    //   max_depth  - the maximum number of stack frames to be included
    //                in the trace.
    //   skip_count - the number of top frames to be skipped; doesn't count
    //                against max_depth.
    virtual string CurrentStackTrace(int max_depth, int skip_count) = 0;
  
    // UponLeavingGTest() should be called immediately before Google Test calls
    // user code. It saves some information about the current stack that
    // CurrentStackTrace() will use to find and hide Google Test stack frames.
    virtual void UponLeavingGTest() = 0;
  
    // This string is inserted in place of stack frames that are part of
    // Google Test's implementation.
    static const char* const kElidedFramesMarker;
  
   private:
    GTEST_DISALLOW_COPY_AND_ASSIGN_(OsStackTraceGetterInterface);
  };
  
  // A working implementation of the OsStackTraceGetterInterface interface.
  class OsStackTraceGetter : public OsStackTraceGetterInterface {
   public:
    OsStackTraceGetter() {}
  
    virtual string CurrentStackTrace(int max_depth, int skip_count);
    virtual void UponLeavingGTest();
  
   private:
    GTEST_DISALLOW_COPY_AND_ASSIGN_(OsStackTraceGetter);
  };
  
  // Information about a Google Test trace point.
  struct TraceInfo {
    const char* file;
    int line;
    std::string message;
  };
  
  // This is the default global test part result reporter used in UnitTestImpl.
  // This class should only be used by UnitTestImpl.
  class DefaultGlobalTestPartResultReporter
    : public TestPartResultReporterInterface {
   public:
    explicit DefaultGlobalTestPartResultReporter(UnitTestImpl* unit_test);
    // Implements the TestPartResultReporterInterface. Reports the test part
    // result in the current test.
    virtual void ReportTestPartResult(const TestPartResult& result);
  
   private:
    UnitTestImpl* const unit_test_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(DefaultGlobalTestPartResultReporter);
  };
  
  // This is the default per thread test part result reporter used in
  // UnitTestImpl. This class should only be used by UnitTestImpl.
  class DefaultPerThreadTestPartResultReporter
      : public TestPartResultReporterInterface {
   public:
    explicit DefaultPerThreadTestPartResultReporter(UnitTestImpl* unit_test);
    // Implements the TestPartResultReporterInterface. The implementation just
    // delegates to the current global test part result reporter of *unit_test_.
    virtual void ReportTestPartResult(const TestPartResult& result);
  
   private:
    UnitTestImpl* const unit_test_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(DefaultPerThreadTestPartResultReporter);
  };
  
  // The private implementation of the UnitTest class.  We don't protect
  // the methods under a mutex, as this class is not accessible by a
  // user and the UnitTest class that delegates work to this class does
  // proper locking.
  class GTEST_API_ UnitTestImpl {
   public:
    explicit UnitTestImpl(UnitTest* parent);
    virtual ~UnitTestImpl();
  
    // There are two different ways to register your own TestPartResultReporter.
    // You can register your own repoter to listen either only for test results
    // from the current thread or for results from all threads.
    // By default, each per-thread test result repoter just passes a new
    // TestPartResult to the global test result reporter, which registers the
    // test part result for the currently running test.
  
    // Returns the global test part result reporter.
    TestPartResultReporterInterface* GetGlobalTestPartResultReporter();
  
    // Sets the global test part result reporter.
    void SetGlobalTestPartResultReporter(
        TestPartResultReporterInterface* reporter);
  
    // Returns the test part result reporter for the current thread.
    TestPartResultReporterInterface* GetTestPartResultReporterForCurrentThread();
  
    // Sets the test part result reporter for the current thread.
    void SetTestPartResultReporterForCurrentThread(
        TestPartResultReporterInterface* reporter);
  
    // Gets the number of successful test cases.
    int successful_test_case_count() const;
  
    // Gets the number of failed test cases.
    int failed_test_case_count() const;
  
    // Gets the number of all test cases.
    int total_test_case_count() const;
  
    // Gets the number of all test cases that contain at least one test
    // that should run.
    int test_case_to_run_count() const;
  
    // Gets the number of successful tests.
    int successful_test_count() const;
  
    // Gets the number of failed tests.
    int failed_test_count() const;
  
    // Gets the number of disabled tests that will be reported in the XML report.
    int reportable_disabled_test_count() const;
  
    // Gets the number of disabled tests.
    int disabled_test_count() const;
  
    // Gets the number of tests to be printed in the XML report.
    int reportable_test_count() const;
  
    // Gets the number of all tests.
    int total_test_count() const;
  
    // Gets the number of tests that should run.
    int test_to_run_count() const;
  
    // Gets the time of the test program start, in ms from the start of the
    // UNIX epoch.
    TimeInMillis start_timestamp() const { return start_timestamp_; }
  
    // Gets the elapsed time, in milliseconds.
    TimeInMillis elapsed_time() const { return elapsed_time_; }
  
    // Returns true iff the unit test passed (i.e. all test cases passed).
    bool Passed() const { return !Failed(); }
  
    // Returns true iff the unit test failed (i.e. some test case failed
    // or something outside of all tests failed).
    bool Failed() const {
      return failed_test_case_count() > 0 || ad_hoc_test_result()->Failed();
    }
  
    // Gets the i-th test case among all the test cases. i can range from 0 to
    // total_test_case_count() - 1. If i is not in that range, returns NULL.
    const TestCase* GetTestCase(int i) const {
      const int index = GetElementOr(test_case_indices_, i, -1);
      return index < 0 ? NULL : test_cases_[i];
    }
  
    // Gets the i-th test case among all the test cases. i can range from 0 to
    // total_test_case_count() - 1. If i is not in that range, returns NULL.
    TestCase* GetMutableTestCase(int i) {
      const int index = GetElementOr(test_case_indices_, i, -1);
      return index < 0 ? NULL : test_cases_[index];
    }
  
    // Provides access to the event listener list.
    TestEventListeners* listeners() { return &listeners_; }
  
    // Returns the TestResult for the test that's currently running, or
    // the TestResult for the ad hoc test if no test is running.
    TestResult* current_test_result();
  
    // Returns the TestResult for the ad hoc test.
    const TestResult* ad_hoc_test_result() const { return &ad_hoc_test_result_; }
  
    // Sets the OS stack trace getter.
    //
    // Does nothing if the input and the current OS stack trace getter
    // are the same; otherwise, deletes the old getter and makes the
    // input the current getter.
    void set_os_stack_trace_getter(OsStackTraceGetterInterface* getter);
  
    // Returns the current OS stack trace getter if it is not NULL;
    // otherwise, creates an OsStackTraceGetter, makes it the current
    // getter, and returns it.
    OsStackTraceGetterInterface* os_stack_trace_getter();
  
    // Returns the current OS stack trace as an std::string.
    //
    // The maximum number of stack frames to be included is specified by
    // the gtest_stack_trace_depth flag.  The skip_count parameter
    // specifies the number of top frames to be skipped, which doesn't
    // count against the number of frames to be included.
    //
    // For example, if Foo() calls Bar(), which in turn calls
    // CurrentOsStackTraceExceptTop(1), Foo() will be included in the
    // trace but Bar() and CurrentOsStackTraceExceptTop() won't.
    std::string CurrentOsStackTraceExceptTop(int skip_count) GTEST_NO_INLINE_;
  
    // Finds and returns a TestCase with the given name.  If one doesn't
    // exist, creates one and returns it.
    //
    // Arguments:
    //
    //   test_case_name: name of the test case
    //   type_param:     the name of the test's type parameter, or NULL if
    //                   this is not a typed or a type-parameterized test.
    //   set_up_tc:      pointer to the function that sets up the test case
    //   tear_down_tc:   pointer to the function that tears down the test case
    TestCase* GetTestCase(const char* test_case_name,
                          const char* type_param,
                          Test::SetUpTestCaseFunc set_up_tc,
                          Test::TearDownTestCaseFunc tear_down_tc);
  
    // Adds a TestInfo to the unit test.
    //
    // Arguments:
    //
    //   set_up_tc:    pointer to the function that sets up the test case
    //   tear_down_tc: pointer to the function that tears down the test case
    //   test_info:    the TestInfo object
    void AddTestInfo(Test::SetUpTestCaseFunc set_up_tc,
                     Test::TearDownTestCaseFunc tear_down_tc,
                     TestInfo* test_info) {
      // In order to support thread-safe death tests, we need to
      // remember the original working directory when the test program
      // was first invoked.  We cannot do this in RUN_ALL_TESTS(), as
      // the user may have changed the current directory before calling
      // RUN_ALL_TESTS().  Therefore we capture the current directory in
      // AddTestInfo(), which is called to register a TEST or TEST_F
      // before main() is reached.
      if (original_working_dir_.IsEmpty()) {
        original_working_dir_.Set(FilePath::GetCurrentDir());
        GTEST_CHECK_(!original_working_dir_.IsEmpty())
            << "Failed to get the current working directory.";
      }
  
      GetTestCase(test_info->test_case_name(),
                  test_info->type_param(),
                  set_up_tc,
                  tear_down_tc)->AddTestInfo(test_info);
    }
  
  #if GTEST_HAS_PARAM_TEST
    // Returns ParameterizedTestCaseRegistry object used to keep track of
    // value-parameterized tests and instantiate and register them.
    internal::ParameterizedTestCaseRegistry& parameterized_test_registry() {
      return parameterized_test_registry_;
    }
  #endif  // GTEST_HAS_PARAM_TEST
  
    // Sets the TestCase object for the test that's currently running.
    void set_current_test_case(TestCase* a_current_test_case) {
      current_test_case_ = a_current_test_case;
    }
  
    // Sets the TestInfo object for the test that's currently running.  If
    // current_test_info is NULL, the assertion results will be stored in
    // ad_hoc_test_result_.
    void set_current_test_info(TestInfo* a_current_test_info) {
      current_test_info_ = a_current_test_info;
    }
  
    // Registers all parameterized tests defined using TEST_P and
    // INSTANTIATE_TEST_CASE_P, creating regular tests for each test/parameter
    // combination. This method can be called more then once; it has guards
    // protecting from registering the tests more then once.  If
    // value-parameterized tests are disabled, RegisterParameterizedTests is
    // present but does nothing.
    void RegisterParameterizedTests();
  
    // Runs all tests in this UnitTest object, prints the result, and
    // returns true if all tests are successful.  If any exception is
    // thrown during a test, this test is considered to be failed, but
    // the rest of the tests will still be run.
    bool RunAllTests();
  
    // Clears the results of all tests, except the ad hoc tests.
    void ClearNonAdHocTestResult() {
      ForEach(test_cases_, TestCase::ClearTestCaseResult);
    }
  
    // Clears the results of ad-hoc test assertions.
    void ClearAdHocTestResult() {
      ad_hoc_test_result_.Clear();
    }
  
    // Adds a TestProperty to the current TestResult object when invoked in a
    // context of a test or a test case, or to the global property set. If the
    // result already contains a property with the same key, the value will be
    // updated.
    void RecordProperty(const TestProperty& test_property);
  
    enum ReactionToSharding {
      HONOR_SHARDING_PROTOCOL,
      IGNORE_SHARDING_PROTOCOL
    };
  
    // Matches the full name of each test against the user-specified
    // filter to decide whether the test should run, then records the
    // result in each TestCase and TestInfo object.
    // If shard_tests == HONOR_SHARDING_PROTOCOL, further filters tests
    // based on sharding variables in the environment.
    // Returns the number of tests that should run.
    int FilterTests(ReactionToSharding shard_tests);
  
    // Prints the names of the tests matching the user-specified filter flag.
    void ListTestsMatchingFilter();
  
    const TestCase* current_test_case() const { return current_test_case_; }
    TestInfo* current_test_info() { return current_test_info_; }
    const TestInfo* current_test_info() const { return current_test_info_; }
  
    // Returns the vector of environments that need to be set-up/torn-down
    // before/after the tests are run.
    std::vector<Environment*>& environments() { return environments_; }
  
    // Getters for the per-thread Google Test trace stack.
    std::vector<TraceInfo>& gtest_trace_stack() {
      return *(gtest_trace_stack_.pointer());
    }
    const std::vector<TraceInfo>& gtest_trace_stack() const {
      return gtest_trace_stack_.get();
    }
  
  #if GTEST_HAS_DEATH_TEST
    void InitDeathTestSubprocessControlInfo() {
      internal_run_death_test_flag_.reset(ParseInternalRunDeathTestFlag());
    }
    // Returns a pointer to the parsed --gtest_internal_run_death_test
    // flag, or NULL if that flag was not specified.
    // This information is useful only in a death test child process.
    // Must not be called before a call to InitGoogleTest.
    const InternalRunDeathTestFlag* internal_run_death_test_flag() const {
      return internal_run_death_test_flag_.get();
    }
  
    // Returns a pointer to the current death test factory.
    internal::DeathTestFactory* death_test_factory() {
      return death_test_factory_.get();
    }
  
    void SuppressTestEventsIfInSubprocess();
  
    friend class ReplaceDeathTestFactory;
  #endif  // GTEST_HAS_DEATH_TEST
  
    // Initializes the event listener performing XML output as specified by
    // UnitTestOptions. Must not be called before InitGoogleTest.
    void ConfigureXmlOutput();
  
  #if GTEST_CAN_STREAM_RESULTS_
    // Initializes the event listener for streaming test results to a socket.
    // Must not be called before InitGoogleTest.
    void ConfigureStreamingOutput();
  #endif
  
    // Performs initialization dependent upon flag values obtained in
    // ParseGoogleTestFlagsOnly.  Is called from InitGoogleTest after the call to
    // ParseGoogleTestFlagsOnly.  In case a user neglects to call InitGoogleTest
    // this function is also called from RunAllTests.  Since this function can be
    // called more than once, it has to be idempotent.
    void PostFlagParsingInit();
  
    // Gets the random seed used at the start of the current test iteration.
    int random_seed() const { return random_seed_; }
  
    // Gets the random number generator.
    internal::Random* random() { return &random_; }
  
    // Shuffles all test cases, and the tests within each test case,
    // making sure that death tests are still run first.
    void ShuffleTests();
  
    // Restores the test cases and tests to their order before the first shuffle.
    void UnshuffleTests();
  
    // Returns the value of GTEST_FLAG(catch_exceptions) at the moment
    // UnitTest::Run() starts.
    bool catch_exceptions() const { return catch_exceptions_; }
  
   private:
    friend class ::testing::UnitTest;
  
    // Used by UnitTest::Run() to capture the state of
    // GTEST_FLAG(catch_exceptions) at the moment it starts.
    void set_catch_exceptions(bool value) { catch_exceptions_ = value; }
  
    // The UnitTest object that owns this implementation object.
    UnitTest* const parent_;
  
    // The working directory when the first TEST() or TEST_F() was
    // executed.
    internal::FilePath original_working_dir_;
  
    // The default test part result reporters.
    DefaultGlobalTestPartResultReporter default_global_test_part_result_reporter_;
    DefaultPerThreadTestPartResultReporter
        default_per_thread_test_part_result_reporter_;
  
    // Points to (but doesn't own) the global test part result reporter.
    TestPartResultReporterInterface* global_test_part_result_repoter_;
  
    // Protects read and write access to global_test_part_result_reporter_.
    internal::Mutex global_test_part_result_reporter_mutex_;
  
    // Points to (but doesn't own) the per-thread test part result reporter.
    internal::ThreadLocal<TestPartResultReporterInterface*>
        per_thread_test_part_result_reporter_;
  
    // The vector of environments that need to be set-up/torn-down
    // before/after the tests are run.
    std::vector<Environment*> environments_;
  
    // The vector of TestCases in their original order.  It owns the
    // elements in the vector.
    std::vector<TestCase*> test_cases_;
  
    // Provides a level of indirection for the test case list to allow
    // easy shuffling and restoring the test case order.  The i-th
    // element of this vector is the index of the i-th test case in the
    // shuffled order.
    std::vector<int> test_case_indices_;
  
  #if GTEST_HAS_PARAM_TEST
    // ParameterizedTestRegistry object used to register value-parameterized
    // tests.
    internal::ParameterizedTestCaseRegistry parameterized_test_registry_;
  
    // Indicates whether RegisterParameterizedTests() has been called already.
    bool parameterized_tests_registered_;
  #endif  // GTEST_HAS_PARAM_TEST
  
    // Index of the last death test case registered.  Initially -1.
    int last_death_test_case_;
  
    // This points to the TestCase for the currently running test.  It
    // changes as Google Test goes through one test case after another.
    // When no test is running, this is set to NULL and Google Test
    // stores assertion results in ad_hoc_test_result_.  Initially NULL.
    TestCase* current_test_case_;
  
    // This points to the TestInfo for the currently running test.  It
    // changes as Google Test goes through one test after another.  When
    // no test is running, this is set to NULL and Google Test stores
    // assertion results in ad_hoc_test_result_.  Initially NULL.
    TestInfo* current_test_info_;
  
    // Normally, a user only writes assertions inside a TEST or TEST_F,
    // or inside a function called by a TEST or TEST_F.  Since Google
    // Test keeps track of which test is current running, it can
    // associate such an assertion with the test it belongs to.
    //
    // If an assertion is encountered when no TEST or TEST_F is running,
    // Google Test attributes the assertion result to an imaginary "ad hoc"
    // test, and records the result in ad_hoc_test_result_.
    TestResult ad_hoc_test_result_;
  
    // The list of event listeners that can be used to track events inside
    // Google Test.
    TestEventListeners listeners_;
  
    // The OS stack trace getter.  Will be deleted when the UnitTest
    // object is destructed.  By default, an OsStackTraceGetter is used,
    // but the user can set this field to use a custom getter if that is
    // desired.
    OsStackTraceGetterInterface* os_stack_trace_getter_;
  
    // True iff PostFlagParsingInit() has been called.
    bool post_flag_parse_init_performed_;
  
    // The random number seed used at the beginning of the test run.
    int random_seed_;
  
    // Our random number generator.
    internal::Random random_;
  
    // The time of the test program start, in ms from the start of the
    // UNIX epoch.
    TimeInMillis start_timestamp_;
  
    // How long the test took to run, in milliseconds.
    TimeInMillis elapsed_time_;
  
  #if GTEST_HAS_DEATH_TEST
    // The decomposed components of the gtest_internal_run_death_test flag,
    // parsed when RUN_ALL_TESTS is called.
    internal::scoped_ptr<InternalRunDeathTestFlag> internal_run_death_test_flag_;
    internal::scoped_ptr<internal::DeathTestFactory> death_test_factory_;
  #endif  // GTEST_HAS_DEATH_TEST
  
    // A per-thread stack of traces created by the SCOPED_TRACE() macro.
    internal::ThreadLocal<std::vector<TraceInfo> > gtest_trace_stack_;
  
    // The value of GTEST_FLAG(catch_exceptions) at the moment RunAllTests()
    // starts.
    bool catch_exceptions_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(UnitTestImpl);
  };  // class UnitTestImpl
  
  // Convenience function for accessing the global UnitTest
  // implementation object.
  inline UnitTestImpl* GetUnitTestImpl() {
    return UnitTest::GetInstance()->impl();
  }
  
  #if GTEST_USES_SIMPLE_RE
  
  // Internal helper functions for implementing the simple regular
  // expression matcher.
  GTEST_API_ bool IsInSet(char ch, const char* str);
  GTEST_API_ bool IsAsciiDigit(char ch);
  GTEST_API_ bool IsAsciiPunct(char ch);
  GTEST_API_ bool IsRepeat(char ch);
  GTEST_API_ bool IsAsciiWhiteSpace(char ch);
  GTEST_API_ bool IsAsciiWordChar(char ch);
  GTEST_API_ bool IsValidEscape(char ch);
  GTEST_API_ bool AtomMatchesChar(bool escaped, char pattern, char ch);
  GTEST_API_ bool ValidateRegex(const char* regex);
  GTEST_API_ bool MatchRegexAtHead(const char* regex, const char* str);
  GTEST_API_ bool MatchRepetitionAndRegexAtHead(
      bool escaped, char ch, char repeat, const char* regex, const char* str);
  GTEST_API_ bool MatchRegexAnywhere(const char* regex, const char* str);
  
  #endif  // GTEST_USES_SIMPLE_RE
  
  // Parses the command line for Google Test flags, without initializing
  // other parts of Google Test.
  GTEST_API_ void ParseGoogleTestFlagsOnly(int* argc, char** argv);
  GTEST_API_ void ParseGoogleTestFlagsOnly(int* argc, wchar_t** argv);
  
  #if GTEST_HAS_DEATH_TEST
  
  // Returns the message describing the last system error, regardless of the
  // platform.
  GTEST_API_ std::string GetLastErrnoDescription();
  
  // Attempts to parse a string into a positive integer pointed to by the
  // number parameter.  Returns true if that is possible.
  // GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we can use
  // it here.
  template <typename Integer>
  bool ParseNaturalNumber(const ::std::string& str, Integer* number) {
    // Fail fast if the given string does not begin with a digit;
    // this bypasses strtoXXX's "optional leading whitespace and plus
    // or minus sign" semantics, which are undesirable here.
    if (str.empty() || !IsDigit(str[0])) {
      return false;
    }
    errno = 0;
  
    char* end;
    // BiggestConvertible is the largest integer type that system-provided
    // string-to-number conversion routines can return.
  
  # if GTEST_OS_WINDOWS && !defined(__GNUC__)
  
    // MSVC and C++ Builder define __int64 instead of the standard long long.
    typedef unsigned __int64 BiggestConvertible;
    const BiggestConvertible parsed = _strtoui64(str.c_str(), &end, 10);
  
  # else
  
    typedef unsigned long long BiggestConvertible;  // NOLINT
    const BiggestConvertible parsed = strtoull(str.c_str(), &end, 10);
  
  # endif  // GTEST_OS_WINDOWS && !defined(__GNUC__)
  
    const bool parse_success = *end == '\0' && errno == 0;
  
    // TODO(vladl@google.com): Convert this to compile time assertion when it is
    // available.
    GTEST_CHECK_(sizeof(Integer) <= sizeof(parsed));
  
    const Integer result = static_cast<Integer>(parsed);
    if (parse_success && static_cast<BiggestConvertible>(result) == parsed) {
      *number = result;
      return true;
    }
    return false;
  }
  #endif  // GTEST_HAS_DEATH_TEST
  
  // TestResult contains some private methods that should be hidden from
  // Google Test user but are required for testing. This class allow our tests
  // to access them.
  //
  // This class is supplied only for the purpose of testing Google Test's own
  // constructs. Do not use it in user tests, either directly or indirectly.
  class TestResultAccessor {
   public:
    static void RecordProperty(TestResult* test_result,
                               const std::string& xml_element,
                               const TestProperty& property) {
      test_result->RecordProperty(xml_element, property);
    }
  
    static void ClearTestPartResults(TestResult* test_result) {
      test_result->ClearTestPartResults();
    }
  
    static const std::vector<testing::TestPartResult>& test_part_results(
        const TestResult& test_result) {
      return test_result.test_part_results();
    }
  };
  
  #if GTEST_CAN_STREAM_RESULTS_
  
  // Streams test results to the given port on the given host machine.
  class GTEST_API_ StreamingListener : public EmptyTestEventListener {
   public:
    // Abstract base class for writing strings to a socket.
    class AbstractSocketWriter {
     public:
      virtual ~AbstractSocketWriter() {}
  
      // Sends a string to the socket.
      virtual void Send(const string& message) = 0;
  
      // Closes the socket.
      virtual void CloseConnection() {}
  
      // Sends a string and a newline to the socket.
      void SendLn(const string& message) {
        Send(message + "\n");
      }
    };
  
    // Concrete class for actually writing strings to a socket.
    class SocketWriter : public AbstractSocketWriter {
     public:
      SocketWriter(const string& host, const string& port)
          : sockfd_(-1), host_name_(host), port_num_(port) {
        MakeConnection();
      }
  
      virtual ~SocketWriter() {
        if (sockfd_ != -1)
          CloseConnection();
      }
  
      // Sends a string to the socket.
      virtual void Send(const string& message) {
        GTEST_CHECK_(sockfd_ != -1)
            << "Send() can be called only when there is a connection.";
  
        const int len = static_cast<int>(message.length());
        if (write(sockfd_, message.c_str(), len) != len) {
          GTEST_LOG_(WARNING)
              << "stream_result_to: failed to stream to "
              << host_name_ << ":" << port_num_;
        }
      }
  
     private:
      // Creates a client socket and connects to the server.
      void MakeConnection();
  
      // Closes the socket.
      void CloseConnection() {
        GTEST_CHECK_(sockfd_ != -1)
            << "CloseConnection() can be called only when there is a connection.";
  
        close(sockfd_);
        sockfd_ = -1;
      }
  
      int sockfd_;  // socket file descriptor
      const string host_name_;
      const string port_num_;
  
      GTEST_DISALLOW_COPY_AND_ASSIGN_(SocketWriter);
    };  // class SocketWriter
  
    // Escapes '=', '&', '%', and '\n' characters in str as "%xx".
    static string UrlEncode(const char* str);
  
    StreamingListener(const string& host, const string& port)
        : socket_writer_(new SocketWriter(host, port)) { Start(); }
  
    explicit StreamingListener(AbstractSocketWriter* socket_writer)
        : socket_writer_(socket_writer) { Start(); }
  
    void OnTestProgramStart(const UnitTest& /* unit_test */) {
      SendLn("event=TestProgramStart");
    }
  
    void OnTestProgramEnd(const UnitTest& unit_test) {
      // Note that Google Test current only report elapsed time for each
      // test iteration, not for the entire test program.
      SendLn("event=TestProgramEnd&passed=" + FormatBool(unit_test.Passed()));
  
      // Notify the streaming server to stop.
      socket_writer_->CloseConnection();
    }
  
    void OnTestIterationStart(const UnitTest& /* unit_test */, int iteration) {
      SendLn("event=TestIterationStart&iteration=" +
             StreamableToString(iteration));
    }
  
    void OnTestIterationEnd(const UnitTest& unit_test, int /* iteration */) {
      SendLn("event=TestIterationEnd&passed=" +
             FormatBool(unit_test.Passed()) + "&elapsed_time=" +
             StreamableToString(unit_test.elapsed_time()) + "ms");
    }
  
    void OnTestCaseStart(const TestCase& test_case) {
      SendLn(std::string("event=TestCaseStart&name=") + test_case.name());
    }
  
    void OnTestCaseEnd(const TestCase& test_case) {
      SendLn("event=TestCaseEnd&passed=" + FormatBool(test_case.Passed())
             + "&elapsed_time=" + StreamableToString(test_case.elapsed_time())
             + "ms");
    }
  
    void OnTestStart(const TestInfo& test_info) {
      SendLn(std::string("event=TestStart&name=") + test_info.name());
    }
  
    void OnTestEnd(const TestInfo& test_info) {
      SendLn("event=TestEnd&passed=" +
             FormatBool((test_info.result())->Passed()) +
             "&elapsed_time=" +
             StreamableToString((test_info.result())->elapsed_time()) + "ms");
    }
  
    void OnTestPartResult(const TestPartResult& test_part_result) {
      const char* file_name = test_part_result.file_name();
      if (file_name == NULL)
        file_name = "";
      SendLn("event=TestPartResult&file=" + UrlEncode(file_name) +
             "&line=" + StreamableToString(test_part_result.line_number()) +
             "&message=" + UrlEncode(test_part_result.message()));
    }
  
   private:
    // Sends the given message and a newline to the socket.
    void SendLn(const string& message) { socket_writer_->SendLn(message); }
  
    // Called at the start of streaming to notify the receiver what
    // protocol we are using.
    void Start() { SendLn("gtest_streaming_protocol_version=1.0"); }
  
    string FormatBool(bool value) { return value ? "1" : "0"; }
  
    const scoped_ptr<AbstractSocketWriter> socket_writer_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(StreamingListener);
  };  // class StreamingListener
  
  #endif  // GTEST_CAN_STREAM_RESULTS_
  
  }  // namespace internal
  }  // namespace testing
  
  #endif  // GTEST_SRC_GTEST_INTERNAL_INL_H_
  #undef GTEST_IMPLEMENTATION_
  
  #if GTEST_OS_WINDOWS
  # define vsnprintf _vsnprintf
  #endif  // GTEST_OS_WINDOWS
  
  namespace testing {
  
  using internal::CountIf;
  using internal::ForEach;
  using internal::GetElementOr;
  using internal::Shuffle;
  
  // Constants.
  
  // A test whose test case name or test name matches this filter is
  // disabled and not run.
  static const char kDisableTestFilter[] = "DISABLED_*:*/DISABLED_*";
  
  // A test case whose name matches this filter is considered a death
  // test case and will be run before test cases whose name doesn't
  // match this filter.
  static const char kDeathTestCaseFilter[] = "*DeathTest:*DeathTest/*";
  
  // A test filter that matches everything.
  static const char kUniversalFilter[] = "*";
  
  // The default output file for XML output.
  static const char kDefaultOutputFile[] = "test_detail.xml";
  
  // The environment variable name for the test shard index.
  static const char kTestShardIndex[] = "GTEST_SHARD_INDEX";
  // The environment variable name for the total number of test shards.
  static const char kTestTotalShards[] = "GTEST_TOTAL_SHARDS";
  // The environment variable name for the test shard status file.
  static const char kTestShardStatusFile[] = "GTEST_SHARD_STATUS_FILE";
  
  namespace internal {
  
  // The text used in failure messages to indicate the start of the
  // stack trace.
  const char kStackTraceMarker[] = "\nStack trace:\n";
  
  // g_help_flag is true iff the --help flag or an equivalent form is
  // specified on the command line.
  bool g_help_flag = false;
  
  }  // namespace internal
  
  static const char* GetDefaultFilter() {
  #ifdef GTEST_TEST_FILTER_ENV_VAR_
    const char* const testbridge_test_only = getenv(GTEST_TEST_FILTER_ENV_VAR_);
    if (testbridge_test_only != NULL) {
      return testbridge_test_only;
    }
  #endif  // GTEST_TEST_FILTER_ENV_VAR_
    return kUniversalFilter;
  }
  
  GTEST_DEFINE_bool_(
      also_run_disabled_tests,
      internal::BoolFromGTestEnv("also_run_disabled_tests", false),
      "Run disabled tests too, in addition to the tests normally being run.");
  
  GTEST_DEFINE_bool_(
      break_on_failure,
      internal::BoolFromGTestEnv("break_on_failure", false),
      "True iff a failed assertion should be a debugger break-point.");
  
  GTEST_DEFINE_bool_(
      catch_exceptions,
      internal::BoolFromGTestEnv("catch_exceptions", true),
      "True iff " GTEST_NAME_
      " should catch exceptions and treat them as test failures.");
  
  GTEST_DEFINE_string_(
      color,
      internal::StringFromGTestEnv("color", "auto"),
      "Whether to use colors in the output.  Valid values: yes, no, "
      "and auto.  'auto' means to use colors if the output is "
      "being sent to a terminal and the TERM environment variable "
      "is set to a terminal type that supports colors.");
  
  GTEST_DEFINE_string_(
      filter,
      internal::StringFromGTestEnv("filter", GetDefaultFilter()),
      "A colon-separated list of glob (not regex) patterns "
      "for filtering the tests to run, optionally followed by a "
      "'-' and a : separated list of negative patterns (tests to "
      "exclude).  A test is run if it matches one of the positive "
      "patterns and does not match any of the negative patterns.");
  
  GTEST_DEFINE_bool_(list_tests, false,
                     "List all tests without running them.");
  
  GTEST_DEFINE_string_(
      output,
      internal::StringFromGTestEnv("output", ""),
      "A format (currently must be \"xml\"), optionally followed "
      "by a colon and an output file name or directory. A directory "
      "is indicated by a trailing pathname separator. "
      "Examples: \"xml:filename.xml\", \"xml::directoryname/\". "
      "If a directory is specified, output files will be created "
      "within that directory, with file-names based on the test "
      "executable's name and, if necessary, made unique by adding "
      "digits.");
  
  GTEST_DEFINE_bool_(
      print_time,
      internal::BoolFromGTestEnv("print_time", true),
      "True iff " GTEST_NAME_
      " should display elapsed time in text output.");
  
  GTEST_DEFINE_int32_(
      random_seed,
      internal::Int32FromGTestEnv("random_seed", 0),
      "Random number seed to use when shuffling test orders.  Must be in range "
      "[1, 99999], or 0 to use a seed based on the current time.");
  
  GTEST_DEFINE_int32_(
      repeat,
      internal::Int32FromGTestEnv("repeat", 1),
      "How many times to repeat each test.  Specify a negative number "
      "for repeating forever.  Useful for shaking out flaky tests.");
  
  GTEST_DEFINE_bool_(
      show_internal_stack_frames, false,
      "True iff " GTEST_NAME_ " should include internal stack frames when "
      "printing test failure stack traces.");
  
  GTEST_DEFINE_bool_(
      shuffle,
      internal::BoolFromGTestEnv("shuffle", false),
      "True iff " GTEST_NAME_
      " should randomize tests' order on every run.");
  
  GTEST_DEFINE_int32_(
      stack_trace_depth,
      internal::Int32FromGTestEnv("stack_trace_depth", kMaxStackTraceDepth),
      "The maximum number of stack frames to print when an "
      "assertion fails.  The valid range is 0 through 100, inclusive.");
  
  GTEST_DEFINE_string_(
      stream_result_to,
      internal::StringFromGTestEnv("stream_result_to", ""),
      "This flag specifies the host name and the port number on which to stream "
      "test results. Example: \"localhost:555\". The flag is effective only on "
      "Linux.");
  
  GTEST_DEFINE_bool_(
      throw_on_failure,
      internal::BoolFromGTestEnv("throw_on_failure", false),
      "When this flag is specified, a failed assertion will throw an exception "
      "if exceptions are enabled or exit the program with a non-zero code "
      "otherwise.");
  
  #if GTEST_USE_OWN_FLAGFILE_FLAG_
  GTEST_DEFINE_string_(
      flagfile,
      internal::StringFromGTestEnv("flagfile", ""),
      "This flag specifies the flagfile to read command-line flags from.");
  #endif  // GTEST_USE_OWN_FLAGFILE_FLAG_
  
  namespace internal {
  
  // Generates a random number from [0, range), using a Linear
  // Congruential Generator (LCG).  Crashes if 'range' is 0 or greater
  // than kMaxRange.
  UInt32 Random::Generate(UInt32 range) {
    // These constants are the same as are used in glibc's rand(3).
    state_ = (1103515245U*state_ + 12345U) % kMaxRange;
  
    GTEST_CHECK_(range > 0)
        << "Cannot generate a number in the range [0, 0).";
    GTEST_CHECK_(range <= kMaxRange)
        << "Generation of a number in [0, " << range << ") was requested, "
        << "but this can only generate numbers in [0, " << kMaxRange << ").";
  
    // Converting via modulus introduces a bit of downward bias, but
    // it's simple, and a linear congruential generator isn't too good
    // to begin with.
    return state_ % range;
  }
  
  // GTestIsInitialized() returns true iff the user has initialized
  // Google Test.  Useful for catching the user mistake of not initializing
  // Google Test before calling RUN_ALL_TESTS().
  static bool GTestIsInitialized() { return GetArgvs().size() > 0; }
  
  // Iterates over a vector of TestCases, keeping a running sum of the
  // results of calling a given int-returning method on each.
  // Returns the sum.
  static int SumOverTestCaseList(const std::vector<TestCase*>& case_list,
                                 int (TestCase::*method)() const) {
    int sum = 0;
    for (size_t i = 0; i < case_list.size(); i++) {
      sum += (case_list[i]->*method)();
    }
    return sum;
  }
  
  // Returns true iff the test case passed.
  static bool TestCasePassed(const TestCase* test_case) {
    return test_case->should_run() && test_case->Passed();
  }
  
  // Returns true iff the test case failed.
  static bool TestCaseFailed(const TestCase* test_case) {
    return test_case->should_run() && test_case->Failed();
  }
  
  // Returns true iff test_case contains at least one test that should
  // run.
  static bool ShouldRunTestCase(const TestCase* test_case) {
    return test_case->should_run();
  }
  
  // AssertHelper constructor.
  AssertHelper::AssertHelper(TestPartResult::Type type,
                             const char* file,
                             int line,
                             const char* message)
      : data_(new AssertHelperData(type, file, line, message)) {
  }
  
  AssertHelper::~AssertHelper() {
    delete data_;
  }
  
  // Message assignment, for assertion streaming support.
  void AssertHelper::operator=(const Message& message) const {
    UnitTest::GetInstance()->
      AddTestPartResult(data_->type, data_->file, data_->line,
                        AppendUserMessage(data_->message, message),
                        UnitTest::GetInstance()->impl()
                        ->CurrentOsStackTraceExceptTop(1)
                        // Skips the stack frame for this function itself.
                        );  // NOLINT
  }
  
  // Mutex for linked pointers.
  GTEST_API_ GTEST_DEFINE_STATIC_MUTEX_(g_linked_ptr_mutex);
  
  // A copy of all command line arguments.  Set by InitGoogleTest().
  ::std::vector<testing::internal::string> g_argvs;
  
  const ::std::vector<testing::internal::string>& GetArgvs() {
  #if defined(GTEST_CUSTOM_GET_ARGVS_)
    return GTEST_CUSTOM_GET_ARGVS_();
  #else  // defined(GTEST_CUSTOM_GET_ARGVS_)
    return g_argvs;
  #endif  // defined(GTEST_CUSTOM_GET_ARGVS_)
  }
  
  // Returns the current application's name, removing directory path if that
  // is present.
  FilePath GetCurrentExecutableName() {
    FilePath result;
  
  #if GTEST_OS_WINDOWS
    result.Set(FilePath(GetArgvs()[0]).RemoveExtension("exe"));
  #else
    result.Set(FilePath(GetArgvs()[0]));
  #endif  // GTEST_OS_WINDOWS
  
    return result.RemoveDirectoryName();
  }
  
  // Functions for processing the gtest_output flag.
  
  // Returns the output format, or "" for normal printed output.
  std::string UnitTestOptions::GetOutputFormat() {
    const char* const gtest_output_flag = GTEST_FLAG(output).c_str();
    if (gtest_output_flag == NULL) return std::string("");
  
    const char* const colon = strchr(gtest_output_flag, ':');
    return (colon == NULL) ?
        std::string(gtest_output_flag) :
        std::string(gtest_output_flag, colon - gtest_output_flag);
  }
  
  // Returns the name of the requested output file, or the default if none
  // was explicitly specified.
  std::string UnitTestOptions::GetAbsolutePathToOutputFile() {
    const char* const gtest_output_flag = GTEST_FLAG(output).c_str();
    if (gtest_output_flag == NULL)
      return "";
  
    const char* const colon = strchr(gtest_output_flag, ':');
    if (colon == NULL)
      return internal::FilePath::ConcatPaths(
          internal::FilePath(
              UnitTest::GetInstance()->original_working_dir()),
          internal::FilePath(kDefaultOutputFile)).string();
  
    internal::FilePath output_name(colon + 1);
    if (!output_name.IsAbsolutePath())
      // TODO(wan@google.com): on Windows \some\path is not an absolute
      // path (as its meaning depends on the current drive), yet the
      // following logic for turning it into an absolute path is wrong.
      // Fix it.
      output_name = internal::FilePath::ConcatPaths(
          internal::FilePath(UnitTest::GetInstance()->original_working_dir()),
          internal::FilePath(colon + 1));
  
    if (!output_name.IsDirectory())
      return output_name.string();
  
    internal::FilePath result(internal::FilePath::GenerateUniqueFileName(
        output_name, internal::GetCurrentExecutableName(),
        GetOutputFormat().c_str()));
    return result.string();
  }
  
  // Returns true iff the wildcard pattern matches the string.  The
  // first ':' or '\0' character in pattern marks the end of it.
  //
  // This recursive algorithm isn't very efficient, but is clear and
  // works well enough for matching test names, which are short.
  bool UnitTestOptions::PatternMatchesString(const char *pattern,
                                             const char *str) {
    switch (*pattern) {
      case '\0':
      case ':':  // Either ':' or '\0' marks the end of the pattern.
        return *str == '\0';
      case '?':  // Matches any single character.
        return *str != '\0' && PatternMatchesString(pattern + 1, str + 1);
      case '*':  // Matches any string (possibly empty) of characters.
        return (*str != '\0' && PatternMatchesString(pattern, str + 1)) ||
            PatternMatchesString(pattern + 1, str);
      default:  // Non-special character.  Matches itself.
        return *pattern == *str &&
            PatternMatchesString(pattern + 1, str + 1);
    }
  }
  
  bool UnitTestOptions::MatchesFilter(
      const std::string& name, const char* filter) {
    const char *cur_pattern = filter;
    for (;;) {
      if (PatternMatchesString(cur_pattern, name.c_str())) {
        return true;
      }
  
      // Finds the next pattern in the filter.
      cur_pattern = strchr(cur_pattern, ':');
  
      // Returns if no more pattern can be found.
      if (cur_pattern == NULL) {
        return false;
      }
  
      // Skips the pattern separater (the ':' character).
      cur_pattern++;
    }
  }
  
  // Returns true iff the user-specified filter matches the test case
  // name and the test name.
  bool UnitTestOptions::FilterMatchesTest(const std::string &test_case_name,
                                          const std::string &test_name) {
    const std::string& full_name = test_case_name + "." + test_name.c_str();
  
    // Split --gtest_filter at '-', if there is one, to separate into
    // positive filter and negative filter portions
    const char* const p = GTEST_FLAG(filter).c_str();
    const char* const dash = strchr(p, '-');
    std::string positive;
    std::string negative;
    if (dash == NULL) {
      positive = GTEST_FLAG(filter).c_str();  // Whole string is a positive filter
      negative = "";
    } else {
      positive = std::string(p, dash);   // Everything up to the dash
      negative = std::string(dash + 1);  // Everything after the dash
      if (positive.empty()) {
        // Treat '-test1' as the same as '*-test1'
        positive = kUniversalFilter;
      }
    }
  
    // A filter is a colon-separated list of patterns.  It matches a
    // test if any pattern in it matches the test.
    return (MatchesFilter(full_name, positive.c_str()) &&
            !MatchesFilter(full_name, negative.c_str()));
  }
  
  #if GTEST_HAS_SEH
  // Returns EXCEPTION_EXECUTE_HANDLER if Google Test should handle the
  // given SEH exception, or EXCEPTION_CONTINUE_SEARCH otherwise.
  // This function is useful as an __except condition.
  int UnitTestOptions::GTestShouldProcessSEH(DWORD exception_code) {
    // Google Test should handle a SEH exception if:
    //   1. the user wants it to, AND
    //   2. this is not a breakpoint exception, AND
    //   3. this is not a C++ exception (VC++ implements them via SEH,
    //      apparently).
    //
    // SEH exception code for C++ exceptions.
    // (see http://support.microsoft.com/kb/185294 for more information).
    const DWORD kCxxExceptionCode = 0xe06d7363;
  
    bool should_handle = true;
  
    if (!GTEST_FLAG(catch_exceptions))
      should_handle = false;
    else if (exception_code == EXCEPTION_BREAKPOINT)
      should_handle = false;
    else if (exception_code == kCxxExceptionCode)
      should_handle = false;
  
    return should_handle ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH;
  }
  #endif  // GTEST_HAS_SEH
  
  }  // namespace internal
  
  // The c'tor sets this object as the test part result reporter used by
  // Google Test.  The 'result' parameter specifies where to report the
  // results. Intercepts only failures from the current thread.
  ScopedFakeTestPartResultReporter::ScopedFakeTestPartResultReporter(
      TestPartResultArray* result)
      : intercept_mode_(INTERCEPT_ONLY_CURRENT_THREAD),
        result_(result) {
    Init();
  }
  
  // The c'tor sets this object as the test part result reporter used by
  // Google Test.  The 'result' parameter specifies where to report the
  // results.
  ScopedFakeTestPartResultReporter::ScopedFakeTestPartResultReporter(
      InterceptMode intercept_mode, TestPartResultArray* result)
      : intercept_mode_(intercept_mode),
        result_(result) {
    Init();
  }
  
  void ScopedFakeTestPartResultReporter::Init() {
    internal::UnitTestImpl* const impl = internal::GetUnitTestImpl();
    if (intercept_mode_ == INTERCEPT_ALL_THREADS) {
      old_reporter_ = impl->GetGlobalTestPartResultReporter();
      impl->SetGlobalTestPartResultReporter(this);
    } else {
      old_reporter_ = impl->GetTestPartResultReporterForCurrentThread();
      impl->SetTestPartResultReporterForCurrentThread(this);
    }
  }
  
  // The d'tor restores the test part result reporter used by Google Test
  // before.
  ScopedFakeTestPartResultReporter::~ScopedFakeTestPartResultReporter() {
    internal::UnitTestImpl* const impl = internal::GetUnitTestImpl();
    if (intercept_mode_ == INTERCEPT_ALL_THREADS) {
      impl->SetGlobalTestPartResultReporter(old_reporter_);
    } else {
      impl->SetTestPartResultReporterForCurrentThread(old_reporter_);
    }
  }
  
  // Increments the test part result count and remembers the result.
  // This method is from the TestPartResultReporterInterface interface.
  void ScopedFakeTestPartResultReporter::ReportTestPartResult(
      const TestPartResult& result) {
    result_->Append(result);
  }
  
  namespace internal {
  
  // Returns the type ID of ::testing::Test.  We should always call this
  // instead of GetTypeId< ::testing::Test>() to get the type ID of
  // testing::Test.  This is to work around a suspected linker bug when
  // using Google Test as a framework on Mac OS X.  The bug causes
  // GetTypeId< ::testing::Test>() to return different values depending
  // on whether the call is from the Google Test framework itself or
  // from user test code.  GetTestTypeId() is guaranteed to always
  // return the same value, as it always calls GetTypeId<>() from the
  // gtest.cc, which is within the Google Test framework.
  TypeId GetTestTypeId() {
    return GetTypeId<Test>();
  }
  
  // The value of GetTestTypeId() as seen from within the Google Test
  // library.  This is solely for testing GetTestTypeId().
  extern const TypeId kTestTypeIdInGoogleTest = GetTestTypeId();
  
  // This predicate-formatter checks that 'results' contains a test part
  // failure of the given type and that the failure message contains the
  // given substring.
  AssertionResult HasOneFailure(const char* /* results_expr */,
                                const char* /* type_expr */,
                                const char* /* substr_expr */,
                                const TestPartResultArray& results,
                                TestPartResult::Type type,
                                const string& substr) {
    const std::string expected(type == TestPartResult::kFatalFailure ?
                          "1 fatal failure" :
                          "1 non-fatal failure");
    Message msg;
    if (results.size() != 1) {
      msg << "Expected: " << expected << "\n"
          << "  Actual: " << results.size() << " failures";
      for (int i = 0; i < results.size(); i++) {
        msg << "\n" << results.GetTestPartResult(i);
      }
      return AssertionFailure() << msg;
    }
  
    const TestPartResult& r = results.GetTestPartResult(0);
    if (r.type() != type) {
      return AssertionFailure() << "Expected: " << expected << "\n"
                                << "  Actual:\n"
                                << r;
    }
  
    if (strstr(r.message(), substr.c_str()) == NULL) {
      return AssertionFailure() << "Expected: " << expected << " containing \""
                                << substr << "\"\n"
                                << "  Actual:\n"
                                << r;
    }
  
    return AssertionSuccess();
  }
  
  // The constructor of SingleFailureChecker remembers where to look up
  // test part results, what type of failure we expect, and what
  // substring the failure message should contain.
  SingleFailureChecker:: SingleFailureChecker(
      const TestPartResultArray* results,
      TestPartResult::Type type,
      const string& substr)
      : results_(results),
        type_(type),
        substr_(substr) {}
  
  // The destructor of SingleFailureChecker verifies that the given
  // TestPartResultArray contains exactly one failure that has the given
  // type and contains the given substring.  If that's not the case, a
  // non-fatal failure will be generated.
  SingleFailureChecker::~SingleFailureChecker() {
    EXPECT_PRED_FORMAT3(HasOneFailure, *results_, type_, substr_);
  }
  
  DefaultGlobalTestPartResultReporter::DefaultGlobalTestPartResultReporter(
      UnitTestImpl* unit_test) : unit_test_(unit_test) {}
  
  void DefaultGlobalTestPartResultReporter::ReportTestPartResult(
      const TestPartResult& result) {
    unit_test_->current_test_result()->AddTestPartResult(result);
    unit_test_->listeners()->repeater()->OnTestPartResult(result);
  }
  
  DefaultPerThreadTestPartResultReporter::DefaultPerThreadTestPartResultReporter(
      UnitTestImpl* unit_test) : unit_test_(unit_test) {}
  
  void DefaultPerThreadTestPartResultReporter::ReportTestPartResult(
      const TestPartResult& result) {
    unit_test_->GetGlobalTestPartResultReporter()->ReportTestPartResult(result);
  }
  
  // Returns the global test part result reporter.
  TestPartResultReporterInterface*
  UnitTestImpl::GetGlobalTestPartResultReporter() {
    internal::MutexLock lock(&global_test_part_result_reporter_mutex_);
    return global_test_part_result_repoter_;
  }
  
  // Sets the global test part result reporter.
  void UnitTestImpl::SetGlobalTestPartResultReporter(
      TestPartResultReporterInterface* reporter) {
    internal::MutexLock lock(&global_test_part_result_reporter_mutex_);
    global_test_part_result_repoter_ = reporter;
  }
  
  // Returns the test part result reporter for the current thread.
  TestPartResultReporterInterface*
  UnitTestImpl::GetTestPartResultReporterForCurrentThread() {
    return per_thread_test_part_result_reporter_.get();
  }
  
  // Sets the test part result reporter for the current thread.
  void UnitTestImpl::SetTestPartResultReporterForCurrentThread(
      TestPartResultReporterInterface* reporter) {
    per_thread_test_part_result_reporter_.set(reporter);
  }
  
  // Gets the number of successful test cases.
  int UnitTestImpl::successful_test_case_count() const {
    return CountIf(test_cases_, TestCasePassed);
  }
  
  // Gets the number of failed test cases.
  int UnitTestImpl::failed_test_case_count() const {
    return CountIf(test_cases_, TestCaseFailed);
  }
  
  // Gets the number of all test cases.
  int UnitTestImpl::total_test_case_count() const {
    return static_cast<int>(test_cases_.size());
  }
  
  // Gets the number of all test cases that contain at least one test
  // that should run.
  int UnitTestImpl::test_case_to_run_count() const {
    return CountIf(test_cases_, ShouldRunTestCase);
  }
  
  // Gets the number of successful tests.
  int UnitTestImpl::successful_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::successful_test_count);
  }
  
  // Gets the number of failed tests.
  int UnitTestImpl::failed_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::failed_test_count);
  }
  
  // Gets the number of disabled tests that will be reported in the XML report.
  int UnitTestImpl::reportable_disabled_test_count() const {
    return SumOverTestCaseList(test_cases_,
                               &TestCase::reportable_disabled_test_count);
  }
  
  // Gets the number of disabled tests.
  int UnitTestImpl::disabled_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::disabled_test_count);
  }
  
  // Gets the number of tests to be printed in the XML report.
  int UnitTestImpl::reportable_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::reportable_test_count);
  }
  
  // Gets the number of all tests.
  int UnitTestImpl::total_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::total_test_count);
  }
  
  // Gets the number of tests that should run.
  int UnitTestImpl::test_to_run_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::test_to_run_count);
  }
  
  // Returns the current OS stack trace as an std::string.
  //
  // The maximum number of stack frames to be included is specified by
  // the gtest_stack_trace_depth flag.  The skip_count parameter
  // specifies the number of top frames to be skipped, which doesn't
  // count against the number of frames to be included.
  //
  // For example, if Foo() calls Bar(), which in turn calls
  // CurrentOsStackTraceExceptTop(1), Foo() will be included in the
  // trace but Bar() and CurrentOsStackTraceExceptTop() won't.
  std::string UnitTestImpl::CurrentOsStackTraceExceptTop(int skip_count) {
    return os_stack_trace_getter()->CurrentStackTrace(
        static_cast<int>(GTEST_FLAG(stack_trace_depth)),
        skip_count + 1
        // Skips the user-specified number of frames plus this function
        // itself.
        );  // NOLINT
  }
  
  // Returns the current time in milliseconds.
  TimeInMillis GetTimeInMillis() {
  #if GTEST_OS_WINDOWS_MOBILE || defined(__BORLANDC__)
    // Difference between 1970-01-01 and 1601-01-01 in milliseconds.
    // http://analogous.blogspot.com/2005/04/epoch.html
    const TimeInMillis kJavaEpochToWinFileTimeDelta =
      static_cast<TimeInMillis>(116444736UL) * 100000UL;
    const DWORD kTenthMicrosInMilliSecond = 10000;
  
    SYSTEMTIME now_systime;
    FILETIME now_filetime;
    ULARGE_INTEGER now_int64;
    // TODO(kenton@google.com): Shouldn't this just use
    //   GetSystemTimeAsFileTime()?
    GetSystemTime(&now_systime);
    if (SystemTimeToFileTime(&now_systime, &now_filetime)) {
      now_int64.LowPart = now_filetime.dwLowDateTime;
      now_int64.HighPart = now_filetime.dwHighDateTime;
      now_int64.QuadPart = (now_int64.QuadPart / kTenthMicrosInMilliSecond) -
        kJavaEpochToWinFileTimeDelta;
      return now_int64.QuadPart;
    }
    return 0;
  #elif GTEST_OS_WINDOWS && !GTEST_HAS_GETTIMEOFDAY_
    __timeb64 now;
  
    // MSVC 8 deprecates _ftime64(), so we want to suppress warning 4996
    // (deprecated function) there.
    // TODO(kenton@google.com): Use GetTickCount()?  Or use
    //   SystemTimeToFileTime()
    GTEST_DISABLE_MSC_WARNINGS_PUSH_(4996)
    _ftime64(&now);
    GTEST_DISABLE_MSC_WARNINGS_POP_()
  
    return static_cast<TimeInMillis>(now.time) * 1000 + now.millitm;
  #elif GTEST_HAS_GETTIMEOFDAY_
    struct timeval now;
    gettimeofday(&now, NULL);
    return static_cast<TimeInMillis>(now.tv_sec) * 1000 + now.tv_usec / 1000;
  #else
  # error "Don't know how to get the current time on your system."
  #endif
  }
  
  // Utilities
  
  // class String.
  
  #if GTEST_OS_WINDOWS_MOBILE
  // Creates a UTF-16 wide string from the given ANSI string, allocating
  // memory using new. The caller is responsible for deleting the return
  // value using delete[]. Returns the wide string, or NULL if the
  // input is NULL.
  LPCWSTR String::AnsiToUtf16(const char* ansi) {
    if (!ansi) return NULL;
    const int length = strlen(ansi);
    const int unicode_length =
        MultiByteToWideChar(CP_ACP, 0, ansi, length,
                            NULL, 0);
    WCHAR* unicode = new WCHAR[unicode_length + 1];
    MultiByteToWideChar(CP_ACP, 0, ansi, length,
                        unicode, unicode_length);
    unicode[unicode_length] = 0;
    return unicode;
  }
  
  // Creates an ANSI string from the given wide string, allocating
  // memory using new. The caller is responsible for deleting the return
  // value using delete[]. Returns the ANSI string, or NULL if the
  // input is NULL.
  const char* String::Utf16ToAnsi(LPCWSTR utf16_str)  {
    if (!utf16_str) return NULL;
    const int ansi_length =
        WideCharToMultiByte(CP_ACP, 0, utf16_str, -1,
                            NULL, 0, NULL, NULL);
    char* ansi = new char[ansi_length + 1];
    WideCharToMultiByte(CP_ACP, 0, utf16_str, -1,
                        ansi, ansi_length, NULL, NULL);
    ansi[ansi_length] = 0;
    return ansi;
  }
  
  #endif  // GTEST_OS_WINDOWS_MOBILE
  
  // Compares two C strings.  Returns true iff they have the same content.
  //
  // Unlike strcmp(), this function can handle NULL argument(s).  A NULL
  // C string is considered different to any non-NULL C string,
  // including the empty string.
  bool String::CStringEquals(const char * lhs, const char * rhs) {
    if ( lhs == NULL ) return rhs == NULL;
  
    if ( rhs == NULL ) return false;
  
    return strcmp(lhs, rhs) == 0;
  }
  
  #if GTEST_HAS_STD_WSTRING || GTEST_HAS_GLOBAL_WSTRING
  
  // Converts an array of wide chars to a narrow string using the UTF-8
  // encoding, and streams the result to the given Message object.
  static void StreamWideCharsToMessage(const wchar_t* wstr, size_t length,
                                       Message* msg) {
    for (size_t i = 0; i != length; ) {  // NOLINT
      if (wstr[i] != L'\0') {
        *msg << WideStringToUtf8(wstr + i, static_cast<int>(length - i));
        while (i != length && wstr[i] != L'\0')
          i++;
      } else {
        *msg << '\0';
        i++;
      }
    }
  }
  
  #endif  // GTEST_HAS_STD_WSTRING || GTEST_HAS_GLOBAL_WSTRING
  
  void SplitString(const ::std::string& str, char delimiter,
                   ::std::vector< ::std::string>* dest) {
    ::std::vector< ::std::string> parsed;
    ::std::string::size_type pos = 0;
    while (::testing::internal::AlwaysTrue()) {
      const ::std::string::size_type colon = str.find(delimiter, pos);
      if (colon == ::std::string::npos) {
        parsed.push_back(str.substr(pos));
        break;
      } else {
        parsed.push_back(str.substr(pos, colon - pos));
        pos = colon + 1;
      }
    }
    dest->swap(parsed);
  }
  
  }  // namespace internal
  
  // Constructs an empty Message.
  // We allocate the stringstream separately because otherwise each use of
  // ASSERT/EXPECT in a procedure adds over 200 bytes to the procedure's
  // stack frame leading to huge stack frames in some cases; gcc does not reuse
  // the stack space.
  Message::Message() : ss_(new ::std::stringstream) {
    // By default, we want there to be enough precision when printing
    // a double to a Message.
    *ss_ << std::setprecision(std::numeric_limits<double>::digits10 + 2);
  }
  
  // These two overloads allow streaming a wide C string to a Message
  // using the UTF-8 encoding.
  Message& Message::operator <<(const wchar_t* wide_c_str) {
    return *this << internal::String::ShowWideCString(wide_c_str);
  }
  Message& Message::operator <<(wchar_t* wide_c_str) {
    return *this << internal::String::ShowWideCString(wide_c_str);
  }
  
  #if GTEST_HAS_STD_WSTRING
  // Converts the given wide string to a narrow string using the UTF-8
  // encoding, and streams the result to this Message object.
  Message& Message::operator <<(const ::std::wstring& wstr) {
    internal::StreamWideCharsToMessage(wstr.c_str(), wstr.length(), this);
    return *this;
  }
  #endif  // GTEST_HAS_STD_WSTRING
  
  #if GTEST_HAS_GLOBAL_WSTRING
  // Converts the given wide string to a narrow string using the UTF-8
  // encoding, and streams the result to this Message object.
  Message& Message::operator <<(const ::wstring& wstr) {
    internal::StreamWideCharsToMessage(wstr.c_str(), wstr.length(), this);
    return *this;
  }
  #endif  // GTEST_HAS_GLOBAL_WSTRING
  
  // Gets the text streamed to this object so far as an std::string.
  // Each '\0' character in the buffer is replaced with "\\0".
  std::string Message::GetString() const {
    return internal::StringStreamToString(ss_.get());
  }
  
  // AssertionResult constructors.
  // Used in EXPECT_TRUE/FALSE(assertion_result).
  AssertionResult::AssertionResult(const AssertionResult& other)
      : success_(other.success_),
        message_(other.message_.get() != NULL ?
                 new ::std::string(*other.message_) :
                 static_cast< ::std::string*>(NULL)) {
  }
  
  // Swaps two AssertionResults.
  void AssertionResult::swap(AssertionResult& other) {
    using std::swap;
    swap(success_, other.success_);
    swap(message_, other.message_);
  }
  
  // Returns the assertion's negation. Used with EXPECT/ASSERT_FALSE.
  AssertionResult AssertionResult::operator!() const {
    AssertionResult negation(!success_);
    if (message_.get() != NULL)
      negation << *message_;
    return negation;
  }
  
  // Makes a successful assertion result.
  AssertionResult AssertionSuccess() {
    return AssertionResult(true);
  }
  
  // Makes a failed assertion result.
  AssertionResult AssertionFailure() {
    return AssertionResult(false);
  }
  
  // Makes a failed assertion result with the given failure message.
  // Deprecated; use AssertionFailure() << message.
  AssertionResult AssertionFailure(const Message& message) {
    return AssertionFailure() << message;
  }
  
  namespace internal {
  
  namespace edit_distance {
  std::vector<EditType> CalculateOptimalEdits(const std::vector<size_t>& left,
                                              const std::vector<size_t>& right) {
    std::vector<std::vector<double> > costs(
        left.size() + 1, std::vector<double>(right.size() + 1));
    std::vector<std::vector<EditType> > best_move(
        left.size() + 1, std::vector<EditType>(right.size() + 1));
  
    // Populate for empty right.
    for (size_t l_i = 0; l_i < costs.size(); ++l_i) {
      costs[l_i][0] = static_cast<double>(l_i);
      best_move[l_i][0] = kRemove;
    }
    // Populate for empty left.
    for (size_t r_i = 1; r_i < costs[0].size(); ++r_i) {
      costs[0][r_i] = static_cast<double>(r_i);
      best_move[0][r_i] = kAdd;
    }
  
    for (size_t l_i = 0; l_i < left.size(); ++l_i) {
      for (size_t r_i = 0; r_i < right.size(); ++r_i) {
        if (left[l_i] == right[r_i]) {
          // Found a match. Consume it.
          costs[l_i + 1][r_i + 1] = costs[l_i][r_i];
          best_move[l_i + 1][r_i + 1] = kMatch;
          continue;
        }
  
        const double add = costs[l_i + 1][r_i];
        const double remove = costs[l_i][r_i + 1];
        const double replace = costs[l_i][r_i];
        if (add < remove && add < replace) {
          costs[l_i + 1][r_i + 1] = add + 1;
          best_move[l_i + 1][r_i + 1] = kAdd;
        } else if (remove < add && remove < replace) {
          costs[l_i + 1][r_i + 1] = remove + 1;
          best_move[l_i + 1][r_i + 1] = kRemove;
        } else {
          // We make replace a little more expensive than add/remove to lower
          // their priority.
          costs[l_i + 1][r_i + 1] = replace + 1.00001;
          best_move[l_i + 1][r_i + 1] = kReplace;
        }
      }
    }
  
    // Reconstruct the best path. We do it in reverse order.
    std::vector<EditType> best_path;
    for (size_t l_i = left.size(), r_i = right.size(); l_i > 0 || r_i > 0;) {
      EditType move = best_move[l_i][r_i];
      best_path.push_back(move);
      l_i -= move != kAdd;
      r_i -= move != kRemove;
    }
    std::reverse(best_path.begin(), best_path.end());
    return best_path;
  }
  
  namespace {
  
  // Helper class to convert string into ids with deduplication.
  class InternalStrings {
   public:
    size_t GetId(const std::string& str) {
      IdMap::iterator it = ids_.find(str);
      if (it != ids_.end()) return it->second;
      size_t id = ids_.size();
      return ids_[str] = id;
    }
  
   private:
    typedef std::map<std::string, size_t> IdMap;
    IdMap ids_;
  };
  
  }  // namespace
  
  std::vector<EditType> CalculateOptimalEdits(
      const std::vector<std::string>& left,
      const std::vector<std::string>& right) {
    std::vector<size_t> left_ids, right_ids;
    {
      InternalStrings intern_table;
      for (size_t i = 0; i < left.size(); ++i) {
        left_ids.push_back(intern_table.GetId(left[i]));
      }
      for (size_t i = 0; i < right.size(); ++i) {
        right_ids.push_back(intern_table.GetId(right[i]));
      }
    }
    return CalculateOptimalEdits(left_ids, right_ids);
  }
  
  namespace {
  
  // Helper class that holds the state for one hunk and prints it out to the
  // stream.
  // It reorders adds/removes when possible to group all removes before all
  // adds. It also adds the hunk header before printint into the stream.
  class Hunk {
   public:
    Hunk(size_t left_start, size_t right_start)
        : left_start_(left_start),
          right_start_(right_start),
          adds_(),
          removes_(),
          common_() {}
  
    void PushLine(char edit, const char* line) {
      switch (edit) {
        case ' ':
          ++common_;
          FlushEdits();
          hunk_.push_back(std::make_pair(' ', line));
          break;
        case '-':
          ++removes_;
          hunk_removes_.push_back(std::make_pair('-', line));
          break;
        case '+':
          ++adds_;
          hunk_adds_.push_back(std::make_pair('+', line));
          break;
      }
    }
  
    void PrintTo(std::ostream* os) {
      PrintHeader(os);
      FlushEdits();
      for (std::list<std::pair<char, const char*> >::const_iterator it =
               hunk_.begin();
           it != hunk_.end(); ++it) {
        *os << it->first << it->second << "\n";
      }
    }
  
    bool has_edits() const { return adds_ || removes_; }
  
   private:
    void FlushEdits() {
      hunk_.splice(hunk_.end(), hunk_removes_);
      hunk_.splice(hunk_.end(), hunk_adds_);
    }
  
    // Print a unified diff header for one hunk.
    // The format is
    //   "@@ -<left_start>,<left_length> +<right_start>,<right_length> @@"
    // where the left/right parts are ommitted if unnecessary.
    void PrintHeader(std::ostream* ss) const {
      *ss << "@@ ";
      if (removes_) {
        *ss << "-" << left_start_ << "," << (removes_ + common_);
      }
      if (removes_ && adds_) {
        *ss << " ";
      }
      if (adds_) {
        *ss << "+" << right_start_ << "," << (adds_ + common_);
      }
      *ss << " @@\n";
    }
  
    size_t left_start_, right_start_;
    size_t adds_, removes_, common_;
    std::list<std::pair<char, const char*> > hunk_, hunk_adds_, hunk_removes_;
  };
  
  }  // namespace
  
  // Create a list of diff hunks in Unified diff format.
  // Each hunk has a header generated by PrintHeader above plus a body with
  // lines prefixed with ' ' for no change, '-' for deletion and '+' for
  // addition.
  // 'context' represents the desired unchanged prefix/suffix around the diff.
  // If two hunks are close enough that their contexts overlap, then they are
  // joined into one hunk.
  std::string CreateUnifiedDiff(const std::vector<std::string>& left,
                                const std::vector<std::string>& right,
                                size_t context) {
    const std::vector<EditType> edits = CalculateOptimalEdits(left, right);
  
    size_t l_i = 0, r_i = 0, edit_i = 0;
    std::stringstream ss;
    while (edit_i < edits.size()) {
      // Find first edit.
      while (edit_i < edits.size() && edits[edit_i] == kMatch) {
        ++l_i;
        ++r_i;
        ++edit_i;
      }
  
      // Find the first line to include in the hunk.
      const size_t prefix_context = std::min(l_i, context);
      Hunk hunk(l_i - prefix_context + 1, r_i - prefix_context + 1);
      for (size_t i = prefix_context; i > 0; --i) {
        hunk.PushLine(' ', left[l_i - i].c_str());
      }
  
      // Iterate the edits until we found enough suffix for the hunk or the input
      // is over.
      size_t n_suffix = 0;
      for (; edit_i < edits.size(); ++edit_i) {
        if (n_suffix >= context) {
          // Continue only if the next hunk is very close.
          std::vector<EditType>::const_iterator it = edits.begin() + edit_i;
          while (it != edits.end() && *it == kMatch) ++it;
          if (it == edits.end() || (it - edits.begin()) - edit_i >= context) {
            // There is no next edit or it is too far away.
            break;
          }
        }
  
        EditType edit = edits[edit_i];
        // Reset count when a non match is found.
        n_suffix = edit == kMatch ? n_suffix + 1 : 0;
  
        if (edit == kMatch || edit == kRemove || edit == kReplace) {
          hunk.PushLine(edit == kMatch ? ' ' : '-', left[l_i].c_str());
        }
        if (edit == kAdd || edit == kReplace) {
          hunk.PushLine('+', right[r_i].c_str());
        }
  
        // Advance indices, depending on edit type.
        l_i += edit != kAdd;
        r_i += edit != kRemove;
      }
  
      if (!hunk.has_edits()) {
        // We are done. We don't want this hunk.
        break;
      }
  
      hunk.PrintTo(&ss);
    }
    return ss.str();
  }
  
  }  // namespace edit_distance
  
  namespace {
  
  // The string representation of the values received in EqFailure() are already
  // escaped. Split them on escaped '\n' boundaries. Leave all other escaped
  // characters the same.
  std::vector<std::string> SplitEscapedString(const std::string& str) {
    std::vector<std::string> lines;
    size_t start = 0, end = str.size();
    if (end > 2 && str[0] == '"' && str[end - 1] == '"') {
      ++start;
      --end;
    }
    bool escaped = false;
    for (size_t i = start; i + 1 < end; ++i) {
      if (escaped) {
        escaped = false;
        if (str[i] == 'n') {
          lines.push_back(str.substr(start, i - start - 1));
          start = i + 1;
        }
      } else {
        escaped = str[i] == '\\';
      }
    }
    lines.push_back(str.substr(start, end - start));
    return lines;
  }
  
  }  // namespace
  
  // Constructs and returns the message for an equality assertion
  // (e.g. ASSERT_EQ, EXPECT_STREQ, etc) failure.
  //
  // The first four parameters are the expressions used in the assertion
  // and their values, as strings.  For example, for ASSERT_EQ(foo, bar)
  // where foo is 5 and bar is 6, we have:
  //
  //   expected_expression: "foo"
  //   actual_expression:   "bar"
  //   expected_value:      "5"
  //   actual_value:        "6"
  //
  // The ignoring_case parameter is true iff the assertion is a
  // *_STRCASEEQ*.  When it's true, the string " (ignoring case)" will
  // be inserted into the message.
  AssertionResult EqFailure(const char* expected_expression,
                            const char* actual_expression,
                            const std::string& expected_value,
                            const std::string& actual_value,
                            bool ignoring_case) {
    Message msg;
    msg << "Value of: " << actual_expression;
    if (actual_value != actual_expression) {
      msg << "\n  Actual: " << actual_value;
    }
  
    msg << "\nExpected: " << expected_expression;
    if (ignoring_case) {
      msg << " (ignoring case)";
    }
    if (expected_value != expected_expression) {
      msg << "\nWhich is: " << expected_value;
    }
  
    if (!expected_value.empty() && !actual_value.empty()) {
      const std::vector<std::string> expected_lines =
          SplitEscapedString(expected_value);
      const std::vector<std::string> actual_lines =
          SplitEscapedString(actual_value);
      if (expected_lines.size() > 1 || actual_lines.size() > 1) {
        msg << "\nWith diff:\n"
            << edit_distance::CreateUnifiedDiff(expected_lines, actual_lines);
      }
    }
  
    return AssertionFailure() << msg;
  }
  
  // Constructs a failure message for Boolean assertions such as EXPECT_TRUE.
  std::string GetBoolAssertionFailureMessage(
      const AssertionResult& assertion_result,
      const char* expression_text,
      const char* actual_predicate_value,
      const char* expected_predicate_value) {
    const char* actual_message = assertion_result.message();
    Message msg;
    msg << "Value of: " << expression_text
        << "\n  Actual: " << actual_predicate_value;
    if (actual_message[0] != '\0')
      msg << " (" << actual_message << ")";
    msg << "\nExpected: " << expected_predicate_value;
    return msg.GetString();
  }
  
  // Helper function for implementing ASSERT_NEAR.
  AssertionResult DoubleNearPredFormat(const char* expr1,
                                       const char* expr2,
                                       const char* abs_error_expr,
                                       double val1,
                                       double val2,
                                       double abs_error) {
    const double diff = fabs(val1 - val2);
    if (diff <= abs_error) return AssertionSuccess();
  
    // TODO(wan): do not print the value of an expression if it's
    // already a literal.
    return AssertionFailure()
        << "The difference between " << expr1 << " and " << expr2
        << " is " << diff << ", which exceeds " << abs_error_expr << ", where\n"
        << expr1 << " evaluates to " << val1 << ",\n"
        << expr2 << " evaluates to " << val2 << ", and\n"
        << abs_error_expr << " evaluates to " << abs_error << ".";
  }
  
  
  // Helper template for implementing FloatLE() and DoubleLE().
  template <typename RawType>
  AssertionResult FloatingPointLE(const char* expr1,
                                  const char* expr2,
                                  RawType val1,
                                  RawType val2) {
    // Returns success if val1 is less than val2,
    if (val1 < val2) {
      return AssertionSuccess();
    }
  
    // or if val1 is almost equal to val2.
    const FloatingPoint<RawType> lhs(val1), rhs(val2);
    if (lhs.AlmostEquals(rhs)) {
      return AssertionSuccess();
    }
  
    // Note that the above two checks will both fail if either val1 or
    // val2 is NaN, as the IEEE floating-point standard requires that
    // any predicate involving a NaN must return false.
  
    ::std::stringstream val1_ss;
    val1_ss << std::setprecision(std::numeric_limits<RawType>::digits10 + 2)
            << val1;
  
    ::std::stringstream val2_ss;
    val2_ss << std::setprecision(std::numeric_limits<RawType>::digits10 + 2)
            << val2;
  
    return AssertionFailure()
        << "Expected: (" << expr1 << ") <= (" << expr2 << ")\n"
        << "  Actual: " << StringStreamToString(&val1_ss) << " vs "
        << StringStreamToString(&val2_ss);
  }
  
  }  // namespace internal
  
  // Asserts that val1 is less than, or almost equal to, val2.  Fails
  // otherwise.  In particular, it fails if either val1 or val2 is NaN.
  AssertionResult FloatLE(const char* expr1, const char* expr2,
                          float val1, float val2) {
    return internal::FloatingPointLE<float>(expr1, expr2, val1, val2);
  }
  
  // Asserts that val1 is less than, or almost equal to, val2.  Fails
  // otherwise.  In particular, it fails if either val1 or val2 is NaN.
  AssertionResult DoubleLE(const char* expr1, const char* expr2,
                           double val1, double val2) {
    return internal::FloatingPointLE<double>(expr1, expr2, val1, val2);
  }
  
  namespace internal {
  
  // The helper function for {ASSERT|EXPECT}_EQ with int or enum
  // arguments.
  AssertionResult CmpHelperEQ(const char* expected_expression,
                              const char* actual_expression,
                              BiggestInt expected,
                              BiggestInt actual) {
    if (expected == actual) {
      return AssertionSuccess();
    }
  
    return EqFailure(expected_expression,
                     actual_expression,
                     FormatForComparisonFailureMessage(expected, actual),
                     FormatForComparisonFailureMessage(actual, expected),
                     false);
  }
  
  // A macro for implementing the helper functions needed to implement
  // ASSERT_?? and EXPECT_?? with integer or enum arguments.  It is here
  // just to avoid copy-and-paste of similar code.
  #define GTEST_IMPL_CMP_HELPER_(op_name, op)\
  AssertionResult CmpHelper##op_name(const char* expr1, const char* expr2, \
                                     BiggestInt val1, BiggestInt val2) {\
    if (val1 op val2) {\
      return AssertionSuccess();\
    } else {\
      return AssertionFailure() \
          << "Expected: (" << expr1 << ") " #op " (" << expr2\
          << "), actual: " << FormatForComparisonFailureMessage(val1, val2)\
          << " vs " << FormatForComparisonFailureMessage(val2, val1);\
    }\
  }
  
  // Implements the helper function for {ASSERT|EXPECT}_NE with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(NE, !=)
  // Implements the helper function for {ASSERT|EXPECT}_LE with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(LE, <=)
  // Implements the helper function for {ASSERT|EXPECT}_LT with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(LT, < )
  // Implements the helper function for {ASSERT|EXPECT}_GE with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(GE, >=)
  // Implements the helper function for {ASSERT|EXPECT}_GT with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(GT, > )
  
  #undef GTEST_IMPL_CMP_HELPER_
  
  // The helper function for {ASSERT|EXPECT}_STREQ.
  AssertionResult CmpHelperSTREQ(const char* expected_expression,
                                 const char* actual_expression,
                                 const char* expected,
                                 const char* actual) {
    if (String::CStringEquals(expected, actual)) {
      return AssertionSuccess();
    }
  
    return EqFailure(expected_expression,
                     actual_expression,
                     PrintToString(expected),
                     PrintToString(actual),
                     false);
  }
  
  // The helper function for {ASSERT|EXPECT}_STRCASEEQ.
  AssertionResult CmpHelperSTRCASEEQ(const char* expected_expression,
                                     const char* actual_expression,
                                     const char* expected,
                                     const char* actual) {
    if (String::CaseInsensitiveCStringEquals(expected, actual)) {
      return AssertionSuccess();
    }
  
    return EqFailure(expected_expression,
                     actual_expression,
                     PrintToString(expected),
                     PrintToString(actual),
                     true);
  }
  
  // The helper function for {ASSERT|EXPECT}_STRNE.
  AssertionResult CmpHelperSTRNE(const char* s1_expression,
                                 const char* s2_expression,
                                 const char* s1,
                                 const char* s2) {
    if (!String::CStringEquals(s1, s2)) {
      return AssertionSuccess();
    } else {
      return AssertionFailure() << "Expected: (" << s1_expression << ") != ("
                                << s2_expression << "), actual: \""
                                << s1 << "\" vs \"" << s2 << "\"";
    }
  }
  
  // The helper function for {ASSERT|EXPECT}_STRCASENE.
  AssertionResult CmpHelperSTRCASENE(const char* s1_expression,
                                     const char* s2_expression,
                                     const char* s1,
                                     const char* s2) {
    if (!String::CaseInsensitiveCStringEquals(s1, s2)) {
      return AssertionSuccess();
    } else {
      return AssertionFailure()
          << "Expected: (" << s1_expression << ") != ("
          << s2_expression << ") (ignoring case), actual: \""
          << s1 << "\" vs \"" << s2 << "\"";
    }
  }
  
  }  // namespace internal
  
  namespace {
  
  // Helper functions for implementing IsSubString() and IsNotSubstring().
  
  // This group of overloaded functions return true iff needle is a
  // substring of haystack.  NULL is considered a substring of itself
  // only.
  
  bool IsSubstringPred(const char* needle, const char* haystack) {
    if (needle == NULL || haystack == NULL)
      return needle == haystack;
  
    return strstr(haystack, needle) != NULL;
  }
  
  bool IsSubstringPred(const wchar_t* needle, const wchar_t* haystack) {
    if (needle == NULL || haystack == NULL)
      return needle == haystack;
  
    return wcsstr(haystack, needle) != NULL;
  }
  
  // StringType here can be either ::std::string or ::std::wstring.
  template <typename StringType>
  bool IsSubstringPred(const StringType& needle,
                       const StringType& haystack) {
    return haystack.find(needle) != StringType::npos;
  }
  
  // This function implements either IsSubstring() or IsNotSubstring(),
  // depending on the value of the expected_to_be_substring parameter.
  // StringType here can be const char*, const wchar_t*, ::std::string,
  // or ::std::wstring.
  template <typename StringType>
  AssertionResult IsSubstringImpl(
      bool expected_to_be_substring,
      const char* needle_expr, const char* haystack_expr,
      const StringType& needle, const StringType& haystack) {
    if (IsSubstringPred(needle, haystack) == expected_to_be_substring)
      return AssertionSuccess();
  
    const bool is_wide_string = sizeof(needle[0]) > 1;
    const char* const begin_string_quote = is_wide_string ? "L\"" : "\"";
    return AssertionFailure()
        << "Value of: " << needle_expr << "\n"
        << "  Actual: " << begin_string_quote << needle << "\"\n"
        << "Expected: " << (expected_to_be_substring ? "" : "not ")
        << "a substring of " << haystack_expr << "\n"
        << "Which is: " << begin_string_quote << haystack << "\"";
  }
  
  }  // namespace
  
  // IsSubstring() and IsNotSubstring() check whether needle is a
  // substring of haystack (NULL is considered a substring of itself
  // only), and return an appropriate error message when they fail.
  
  AssertionResult IsSubstring(
      const char* needle_expr, const char* haystack_expr,
      const char* needle, const char* haystack) {
    return IsSubstringImpl(true, needle_expr, haystack_expr, needle, haystack);
  }
  
  AssertionResult IsSubstring(
      const char* needle_expr, const char* haystack_expr,
      const wchar_t* needle, const wchar_t* haystack) {
    return IsSubstringImpl(true, needle_expr, haystack_expr, needle, haystack);
  }
  
  AssertionResult IsNotSubstring(
      const char* needle_expr, const char* haystack_expr,
      const char* needle, const char* haystack) {
    return IsSubstringImpl(false, needle_expr, haystack_expr, needle, haystack);
  }
  
  AssertionResult IsNotSubstring(
      const char* needle_expr, const char* haystack_expr,
      const wchar_t* needle, const wchar_t* haystack) {
    return IsSubstringImpl(false, needle_expr, haystack_expr, needle, haystack);
  }
  
  AssertionResult IsSubstring(
      const char* needle_expr, const char* haystack_expr,
      const ::std::string& needle, const ::std::string& haystack) {
    return IsSubstringImpl(true, needle_expr, haystack_expr, needle, haystack);
  }
  
  AssertionResult IsNotSubstring(
      const char* needle_expr, const char* haystack_expr,
      const ::std::string& needle, const ::std::string& haystack) {
    return IsSubstringImpl(false, needle_expr, haystack_expr, needle, haystack);
  }
  
  #if GTEST_HAS_STD_WSTRING
  AssertionResult IsSubstring(
      const char* needle_expr, const char* haystack_expr,
      const ::std::wstring& needle, const ::std::wstring& haystack) {
    return IsSubstringImpl(true, needle_expr, haystack_expr, needle, haystack);
  }
  
  AssertionResult IsNotSubstring(
      const char* needle_expr, const char* haystack_expr,
      const ::std::wstring& needle, const ::std::wstring& haystack) {
    return IsSubstringImpl(false, needle_expr, haystack_expr, needle, haystack);
  }
  #endif  // GTEST_HAS_STD_WSTRING
  
  namespace internal {
  
  #if GTEST_OS_WINDOWS
  
  namespace {
  
  // Helper function for IsHRESULT{SuccessFailure} predicates
  AssertionResult HRESULTFailureHelper(const char* expr,
                                       const char* expected,
                                       long hr) {  // NOLINT
  # if GTEST_OS_WINDOWS_MOBILE
  
    // Windows CE doesn't support FormatMessage.
    const char error_text[] = "";
  
  # else
  
    // Looks up the human-readable system message for the HRESULT code
    // and since we're not passing any params to FormatMessage, we don't
    // want inserts expanded.
    const DWORD kFlags = FORMAT_MESSAGE_FROM_SYSTEM |
                         FORMAT_MESSAGE_IGNORE_INSERTS;
    const DWORD kBufSize = 4096;
    // Gets the system's human readable message string for this HRESULT.
    char error_text[kBufSize] = { '\0' };
    DWORD message_length = ::FormatMessageA(kFlags,
                                            0,  // no source, we're asking system
                                            hr,  // the error
                                            0,  // no line width restrictions
                                            error_text,  // output buffer
                                            kBufSize,  // buf size
                                            NULL);  // no arguments for inserts
    // Trims tailing white space (FormatMessage leaves a trailing CR-LF)
    for (; message_length && IsSpace(error_text[message_length - 1]);
            --message_length) {
      error_text[message_length - 1] = '\0';
    }
  
  # endif  // GTEST_OS_WINDOWS_MOBILE
  
    const std::string error_hex("0x" + String::FormatHexInt(hr));
    return ::testing::AssertionFailure()
        << "Expected: " << expr << " " << expected << ".\n"
        << "  Actual: " << error_hex << " " << error_text << "\n";
  }
  
  }  // namespace
  
  AssertionResult IsHRESULTSuccess(const char* expr, long hr) {  // NOLINT
    if (SUCCEEDED(hr)) {
      return AssertionSuccess();
    }
    return HRESULTFailureHelper(expr, "succeeds", hr);
  }
  
  AssertionResult IsHRESULTFailure(const char* expr, long hr) {  // NOLINT
    if (FAILED(hr)) {
      return AssertionSuccess();
    }
    return HRESULTFailureHelper(expr, "fails", hr);
  }
  
  #endif  // GTEST_OS_WINDOWS
  
  // Utility functions for encoding Unicode text (wide strings) in
  // UTF-8.
  
  // A Unicode code-point can have upto 21 bits, and is encoded in UTF-8
  // like this:
  //
  // Code-point length   Encoding
  //   0 -  7 bits       0xxxxxxx
  //   8 - 11 bits       110xxxxx 10xxxxxx
  //  12 - 16 bits       1110xxxx 10xxxxxx 10xxxxxx
  //  17 - 21 bits       11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
  
  // The maximum code-point a one-byte UTF-8 sequence can represent.
  const UInt32 kMaxCodePoint1 = (static_cast<UInt32>(1) <<  7) - 1;
  
  // The maximum code-point a two-byte UTF-8 sequence can represent.
  const UInt32 kMaxCodePoint2 = (static_cast<UInt32>(1) << (5 + 6)) - 1;
  
  // The maximum code-point a three-byte UTF-8 sequence can represent.
  const UInt32 kMaxCodePoint3 = (static_cast<UInt32>(1) << (4 + 2*6)) - 1;
  
  // The maximum code-point a four-byte UTF-8 sequence can represent.
  const UInt32 kMaxCodePoint4 = (static_cast<UInt32>(1) << (3 + 3*6)) - 1;
  
  // Chops off the n lowest bits from a bit pattern.  Returns the n
  // lowest bits.  As a side effect, the original bit pattern will be
  // shifted to the right by n bits.
  inline UInt32 ChopLowBits(UInt32* bits, int n) {
    const UInt32 low_bits = *bits & ((static_cast<UInt32>(1) << n) - 1);
    *bits >>= n;
    return low_bits;
  }
  
  // Converts a Unicode code point to a narrow string in UTF-8 encoding.
  // code_point parameter is of type UInt32 because wchar_t may not be
  // wide enough to contain a code point.
  // If the code_point is not a valid Unicode code point
  // (i.e. outside of Unicode range U+0 to U+10FFFF) it will be converted
  // to "(Invalid Unicode 0xXXXXXXXX)".
  std::string CodePointToUtf8(UInt32 code_point) {
    if (code_point > kMaxCodePoint4) {
      return "(Invalid Unicode 0x" + String::FormatHexInt(code_point) + ")";
    }
  
    char str[5];  // Big enough for the largest valid code point.
    if (code_point <= kMaxCodePoint1) {
      str[1] = '\0';
      str[0] = static_cast<char>(code_point);                          // 0xxxxxxx
    } else if (code_point <= kMaxCodePoint2) {
      str[2] = '\0';
      str[1] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
      str[0] = static_cast<char>(0xC0 | code_point);                   // 110xxxxx
    } else if (code_point <= kMaxCodePoint3) {
      str[3] = '\0';
      str[2] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
      str[1] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
      str[0] = static_cast<char>(0xE0 | code_point);                   // 1110xxxx
    } else {  // code_point <= kMaxCodePoint4
      str[4] = '\0';
      str[3] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
      str[2] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
      str[1] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
      str[0] = static_cast<char>(0xF0 | code_point);                   // 11110xxx
    }
    return str;
  }
  
  // The following two functions only make sense if the the system
  // uses UTF-16 for wide string encoding. All supported systems
  // with 16 bit wchar_t (Windows, Cygwin, Symbian OS) do use UTF-16.
  
  // Determines if the arguments constitute UTF-16 surrogate pair
  // and thus should be combined into a single Unicode code point
  // using CreateCodePointFromUtf16SurrogatePair.
  inline bool IsUtf16SurrogatePair(wchar_t first, wchar_t second) {
    return sizeof(wchar_t) == 2 &&
        (first & 0xFC00) == 0xD800 && (second & 0xFC00) == 0xDC00;
  }
  
  // Creates a Unicode code point from UTF16 surrogate pair.
  inline UInt32 CreateCodePointFromUtf16SurrogatePair(wchar_t first,
                                                      wchar_t second) {
    const UInt32 mask = (1 << 10) - 1;
    return (sizeof(wchar_t) == 2) ?
        (((first & mask) << 10) | (second & mask)) + 0x10000 :
        // This function should not be called when the condition is
        // false, but we provide a sensible default in case it is.
        static_cast<UInt32>(first);
  }
  
  // Converts a wide string to a narrow string in UTF-8 encoding.
  // The wide string is assumed to have the following encoding:
  //   UTF-16 if sizeof(wchar_t) == 2 (on Windows, Cygwin, Symbian OS)
  //   UTF-32 if sizeof(wchar_t) == 4 (on Linux)
  // Parameter str points to a null-terminated wide string.
  // Parameter num_chars may additionally limit the number
  // of wchar_t characters processed. -1 is used when the entire string
  // should be processed.
  // If the string contains code points that are not valid Unicode code points
  // (i.e. outside of Unicode range U+0 to U+10FFFF) they will be output
  // as '(Invalid Unicode 0xXXXXXXXX)'. If the string is in UTF16 encoding
  // and contains invalid UTF-16 surrogate pairs, values in those pairs
  // will be encoded as individual Unicode characters from Basic Normal Plane.
  std::string WideStringToUtf8(const wchar_t* str, int num_chars) {
    if (num_chars == -1)
      num_chars = static_cast<int>(wcslen(str));
  
    ::std::stringstream stream;
    for (int i = 0; i < num_chars; ++i) {
      UInt32 unicode_code_point;
  
      if (str[i] == L'\0') {
        break;
      } else if (i + 1 < num_chars && IsUtf16SurrogatePair(str[i], str[i + 1])) {
        unicode_code_point = CreateCodePointFromUtf16SurrogatePair(str[i],
                                                                   str[i + 1]);
        i++;
      } else {
        unicode_code_point = static_cast<UInt32>(str[i]);
      }
  
      stream << CodePointToUtf8(unicode_code_point);
    }
    return StringStreamToString(&stream);
  }
  
  // Converts a wide C string to an std::string using the UTF-8 encoding.
  // NULL will be converted to "(null)".
  std::string String::ShowWideCString(const wchar_t * wide_c_str) {
    if (wide_c_str == NULL)  return "(null)";
  
    return internal::WideStringToUtf8(wide_c_str, -1);
  }
  
  // Compares two wide C strings.  Returns true iff they have the same
  // content.
  //
  // Unlike wcscmp(), this function can handle NULL argument(s).  A NULL
  // C string is considered different to any non-NULL C string,
  // including the empty string.
  bool String::WideCStringEquals(const wchar_t * lhs, const wchar_t * rhs) {
    if (lhs == NULL) return rhs == NULL;
  
    if (rhs == NULL) return false;
  
    return wcscmp(lhs, rhs) == 0;
  }
  
  // Helper function for *_STREQ on wide strings.
  AssertionResult CmpHelperSTREQ(const char* expected_expression,
                                 const char* actual_expression,
                                 const wchar_t* expected,
                                 const wchar_t* actual) {
    if (String::WideCStringEquals(expected, actual)) {
      return AssertionSuccess();
    }
  
    return EqFailure(expected_expression,
                     actual_expression,
                     PrintToString(expected),
                     PrintToString(actual),
                     false);
  }
  
  // Helper function for *_STRNE on wide strings.
  AssertionResult CmpHelperSTRNE(const char* s1_expression,
                                 const char* s2_expression,
                                 const wchar_t* s1,
                                 const wchar_t* s2) {
    if (!String::WideCStringEquals(s1, s2)) {
      return AssertionSuccess();
    }
  
    return AssertionFailure() << "Expected: (" << s1_expression << ") != ("
                              << s2_expression << "), actual: "
                              << PrintToString(s1)
                              << " vs " << PrintToString(s2);
  }
  
  // Compares two C strings, ignoring case.  Returns true iff they have
  // the same content.
  //
  // Unlike strcasecmp(), this function can handle NULL argument(s).  A
  // NULL C string is considered different to any non-NULL C string,
  // including the empty string.
  bool String::CaseInsensitiveCStringEquals(const char * lhs, const char * rhs) {
    if (lhs == NULL)
      return rhs == NULL;
    if (rhs == NULL)
      return false;
    return posix::StrCaseCmp(lhs, rhs) == 0;
  }
  
    // Compares two wide C strings, ignoring case.  Returns true iff they
    // have the same content.
    //
    // Unlike wcscasecmp(), this function can handle NULL argument(s).
    // A NULL C string is considered different to any non-NULL wide C string,
    // including the empty string.
    // NB: The implementations on different platforms slightly differ.
    // On windows, this method uses _wcsicmp which compares according to LC_CTYPE
    // environment variable. On GNU platform this method uses wcscasecmp
    // which compares according to LC_CTYPE category of the current locale.
    // On MacOS X, it uses towlower, which also uses LC_CTYPE category of the
    // current locale.
  bool String::CaseInsensitiveWideCStringEquals(const wchar_t* lhs,
                                                const wchar_t* rhs) {
    if (lhs == NULL) return rhs == NULL;
  
    if (rhs == NULL) return false;
  
  #if GTEST_OS_WINDOWS
    return _wcsicmp(lhs, rhs) == 0;
  #elif GTEST_OS_LINUX && !GTEST_OS_LINUX_ANDROID
    return wcscasecmp(lhs, rhs) == 0;
  #else
    // Android, Mac OS X and Cygwin don't define wcscasecmp.
    // Other unknown OSes may not define it either.
    wint_t left, right;
    do {
      left = towlower(*lhs++);
      right = towlower(*rhs++);
    } while (left && left == right);
    return left == right;
  #endif  // OS selector
  }
  
  // Returns true iff str ends with the given suffix, ignoring case.
  // Any string is considered to end with an empty suffix.
  bool String::EndsWithCaseInsensitive(
      const std::string& str, const std::string& suffix) {
    const size_t str_len = str.length();
    const size_t suffix_len = suffix.length();
    return (str_len >= suffix_len) &&
           CaseInsensitiveCStringEquals(str.c_str() + str_len - suffix_len,
                                        suffix.c_str());
  }
  
  // Formats an int value as "%02d".
  std::string String::FormatIntWidth2(int value) {
    std::stringstream ss;
    ss << std::setfill('0') << std::setw(2) << value;
    return ss.str();
  }
  
  // Formats an int value as "%X".
  std::string String::FormatHexInt(int value) {
    std::stringstream ss;
    ss << std::hex << std::uppercase << value;
    return ss.str();
  }
  
  // Formats a byte as "%02X".
  std::string String::FormatByte(unsigned char value) {
    std::stringstream ss;
    ss << std::setfill('0') << std::setw(2) << std::hex << std::uppercase
       << static_cast<unsigned int>(value);
    return ss.str();
  }
  
  // Converts the buffer in a stringstream to an std::string, converting NUL
  // bytes to "\\0" along the way.
  std::string StringStreamToString(::std::stringstream* ss) {
    const ::std::string& str = ss->str();
    const char* const start = str.c_str();
    const char* const end = start + str.length();
  
    std::string result;
    result.reserve(2 * (end - start));
    for (const char* ch = start; ch != end; ++ch) {
      if (*ch == '\0') {
        result += "\\0";  // Replaces NUL with "\\0";
      } else {
        result += *ch;
      }
    }
  
    return result;
  }
  
  // Appends the user-supplied message to the Google-Test-generated message.
  std::string AppendUserMessage(const std::string& gtest_msg,
                                const Message& user_msg) {
    // Appends the user message if it's non-empty.
    const std::string user_msg_string = user_msg.GetString();
    if (user_msg_string.empty()) {
      return gtest_msg;
    }
  
    return gtest_msg + "\n" + user_msg_string;
  }
  
  }  // namespace internal
  
  // class TestResult
  
  // Creates an empty TestResult.
  TestResult::TestResult()
      : death_test_count_(0),
        elapsed_time_(0) {
  }
  
  // D'tor.
  TestResult::~TestResult() {
  }
  
  // Returns the i-th test part result among all the results. i can
  // range from 0 to total_part_count() - 1. If i is not in that range,
  // aborts the program.
  const TestPartResult& TestResult::GetTestPartResult(int i) const {
    if (i < 0 || i >= total_part_count())
      internal::posix::Abort();
    return test_part_results_.at(i);
  }
  
  // Returns the i-th test property. i can range from 0 to
  // test_property_count() - 1. If i is not in that range, aborts the
  // program.
  const TestProperty& TestResult::GetTestProperty(int i) const {
    if (i < 0 || i >= test_property_count())
      internal::posix::Abort();
    return test_properties_.at(i);
  }
  
  // Clears the test part results.
  void TestResult::ClearTestPartResults() {
    test_part_results_.clear();
  }
  
  // Adds a test part result to the list.
  void TestResult::AddTestPartResult(const TestPartResult& test_part_result) {
    test_part_results_.push_back(test_part_result);
  }
  
  // Adds a test property to the list. If a property with the same key as the
  // supplied property is already represented, the value of this test_property
  // replaces the old value for that key.
  void TestResult::RecordProperty(const std::string& xml_element,
                                  const TestProperty& test_property) {
    if (!ValidateTestProperty(xml_element, test_property)) {
      return;
    }
    internal::MutexLock lock(&test_properites_mutex_);
    const std::vector<TestProperty>::iterator property_with_matching_key =
        std::find_if(test_properties_.begin(), test_properties_.end(),
                     internal::TestPropertyKeyIs(test_property.key()));
    if (property_with_matching_key == test_properties_.end()) {
      test_properties_.push_back(test_property);
      return;
    }
    property_with_matching_key->SetValue(test_property.value());
  }
  
  // The list of reserved attributes used in the <testsuites> element of XML
  // output.
  static const char* const kReservedTestSuitesAttributes[] = {
    "disabled",
    "errors",
    "failures",
    "name",
    "random_seed",
    "tests",
    "time",
    "timestamp"
  };
  
  // The list of reserved attributes used in the <testsuite> element of XML
  // output.
  static const char* const kReservedTestSuiteAttributes[] = {
    "disabled",
    "errors",
    "failures",
    "name",
    "tests",
    "time"
  };
  
  // The list of reserved attributes used in the <testcase> element of XML output.
  static const char* const kReservedTestCaseAttributes[] = {
    "classname",
    "name",
    "status",
    "time",
    "type_param",
    "value_param"
  };
  
  template <int kSize>
  std::vector<std::string> ArrayAsVector(const char* const (&array)[kSize]) {
    return std::vector<std::string>(array, array + kSize);
  }
  
  static std::vector<std::string> GetReservedAttributesForElement(
      const std::string& xml_element) {
    if (xml_element == "testsuites") {
      return ArrayAsVector(kReservedTestSuitesAttributes);
    } else if (xml_element == "testsuite") {
      return ArrayAsVector(kReservedTestSuiteAttributes);
    } else if (xml_element == "testcase") {
      return ArrayAsVector(kReservedTestCaseAttributes);
    } else {
      GTEST_CHECK_(false) << "Unrecognized xml_element provided: " << xml_element;
    }
    // This code is unreachable but some compilers may not realizes that.
    return std::vector<std::string>();
  }
  
  static std::string FormatWordList(const std::vector<std::string>& words) {
    Message word_list;
    for (size_t i = 0; i < words.size(); ++i) {
      if (i > 0 && words.size() > 2) {
        word_list << ", ";
      }
      if (i == words.size() - 1) {
        word_list << "and ";
      }
      word_list << "'" << words[i] << "'";
    }
    return word_list.GetString();
  }
  
  bool ValidateTestPropertyName(const std::string& property_name,
                                const std::vector<std::string>& reserved_names) {
    if (std::find(reserved_names.begin(), reserved_names.end(), property_name) !=
            reserved_names.end()) {
      ADD_FAILURE() << "Reserved key used in RecordProperty(): " << property_name
                    << " (" << FormatWordList(reserved_names)
                    << " are reserved by " << GTEST_NAME_ << ")";
      return false;
    }
    return true;
  }
  
  // Adds a failure if the key is a reserved attribute of the element named
  // xml_element.  Returns true if the property is valid.
  bool TestResult::ValidateTestProperty(const std::string& xml_element,
                                        const TestProperty& test_property) {
    return ValidateTestPropertyName(test_property.key(),
                                    GetReservedAttributesForElement(xml_element));
  }
  
  // Clears the object.
  void TestResult::Clear() {
    test_part_results_.clear();
    test_properties_.clear();
    death_test_count_ = 0;
    elapsed_time_ = 0;
  }
  
  // Returns true iff the test failed.
  bool TestResult::Failed() const {
    for (int i = 0; i < total_part_count(); ++i) {
      if (GetTestPartResult(i).failed())
        return true;
    }
    return false;
  }
  
  // Returns true iff the test part fatally failed.
  static bool TestPartFatallyFailed(const TestPartResult& result) {
    return result.fatally_failed();
  }
  
  // Returns true iff the test fatally failed.
  bool TestResult::HasFatalFailure() const {
    return CountIf(test_part_results_, TestPartFatallyFailed) > 0;
  }
  
  // Returns true iff the test part non-fatally failed.
  static bool TestPartNonfatallyFailed(const TestPartResult& result) {
    return result.nonfatally_failed();
  }
  
  // Returns true iff the test has a non-fatal failure.
  bool TestResult::HasNonfatalFailure() const {
    return CountIf(test_part_results_, TestPartNonfatallyFailed) > 0;
  }
  
  // Gets the number of all test parts.  This is the sum of the number
  // of successful test parts and the number of failed test parts.
  int TestResult::total_part_count() const {
    return static_cast<int>(test_part_results_.size());
  }
  
  // Returns the number of the test properties.
  int TestResult::test_property_count() const {
    return static_cast<int>(test_properties_.size());
  }
  
  // class Test
  
  // Creates a Test object.
  
  // The c'tor saves the states of all flags.
  Test::Test()
      : gtest_flag_saver_(new GTEST_FLAG_SAVER_) {
  }
  
  // The d'tor restores the states of all flags.  The actual work is
  // done by the d'tor of the gtest_flag_saver_ field, and thus not
  // visible here.
  Test::~Test() {
  }
  
  // Sets up the test fixture.
  //
  // A sub-class may override this.
  void Test::SetUp() {
  }
  
  // Tears down the test fixture.
  //
  // A sub-class may override this.
  void Test::TearDown() {
  }
  
  // Allows user supplied key value pairs to be recorded for later output.
  void Test::RecordProperty(const std::string& key, const std::string& value) {
    UnitTest::GetInstance()->RecordProperty(key, value);
  }
  
  // Allows user supplied key value pairs to be recorded for later output.
  void Test::RecordProperty(const std::string& key, int value) {
    Message value_message;
    value_message << value;
    RecordProperty(key, value_message.GetString().c_str());
  }
  
  namespace internal {
  
  void ReportFailureInUnknownLocation(TestPartResult::Type result_type,
                                      const std::string& message) {
    // This function is a friend of UnitTest and as such has access to
    // AddTestPartResult.
    UnitTest::GetInstance()->AddTestPartResult(
        result_type,
        NULL,  // No info about the source file where the exception occurred.
        -1,    // We have no info on which line caused the exception.
        message,
        "");   // No stack trace, either.
  }
  
  }  // namespace internal
  
  // Google Test requires all tests in the same test case to use the same test
  // fixture class.  This function checks if the current test has the
  // same fixture class as the first test in the current test case.  If
  // yes, it returns true; otherwise it generates a Google Test failure and
  // returns false.
  bool Test::HasSameFixtureClass() {
    internal::UnitTestImpl* const impl = internal::GetUnitTestImpl();
    const TestCase* const test_case = impl->current_test_case();
  
    // Info about the first test in the current test case.
    const TestInfo* const first_test_info = test_case->test_info_list()[0];
    const internal::TypeId first_fixture_id = first_test_info->fixture_class_id_;
    const char* const first_test_name = first_test_info->name();
  
    // Info about the current test.
    const TestInfo* const this_test_info = impl->current_test_info();
    const internal::TypeId this_fixture_id = this_test_info->fixture_class_id_;
    const char* const this_test_name = this_test_info->name();
  
    if (this_fixture_id != first_fixture_id) {
      // Is the first test defined using TEST?
      const bool first_is_TEST = first_fixture_id == internal::GetTestTypeId();
      // Is this test defined using TEST?
      const bool this_is_TEST = this_fixture_id == internal::GetTestTypeId();
  
      if (first_is_TEST || this_is_TEST) {
        // Both TEST and TEST_F appear in same test case, which is incorrect.
        // Tell the user how to fix this.
  
        // Gets the name of the TEST and the name of the TEST_F.  Note
        // that first_is_TEST and this_is_TEST cannot both be true, as
        // the fixture IDs are different for the two tests.
        const char* const TEST_name =
            first_is_TEST ? first_test_name : this_test_name;
        const char* const TEST_F_name =
            first_is_TEST ? this_test_name : first_test_name;
  
        ADD_FAILURE()
            << "All tests in the same test case must use the same test fixture\n"
            << "class, so mixing TEST_F and TEST in the same test case is\n"
            << "illegal.  In test case " << this_test_info->test_case_name()
            << ",\n"
            << "test " << TEST_F_name << " is defined using TEST_F but\n"
            << "test " << TEST_name << " is defined using TEST.  You probably\n"
            << "want to change the TEST to TEST_F or move it to another test\n"
            << "case.";
      } else {
        // Two fixture classes with the same name appear in two different
        // namespaces, which is not allowed. Tell the user how to fix this.
        ADD_FAILURE()
            << "All tests in the same test case must use the same test fixture\n"
            << "class.  However, in test case "
            << this_test_info->test_case_name() << ",\n"
            << "you defined test " << first_test_name
            << " and test " << this_test_name << "\n"
            << "using two different test fixture classes.  This can happen if\n"
            << "the two classes are from different namespaces or translation\n"
            << "units and have the same name.  You should probably rename one\n"
            << "of the classes to put the tests into different test cases.";
      }
      return false;
    }
  
    return true;
  }
  
  #if GTEST_HAS_SEH
  
  // Adds an "exception thrown" fatal failure to the current test.  This
  // function returns its result via an output parameter pointer because VC++
  // prohibits creation of objects with destructors on stack in functions
  // using __try (see error C2712).
  static std::string* FormatSehExceptionMessage(DWORD exception_code,
                                                const char* location) {
    Message message;
    message << "SEH exception with code 0x" << std::setbase(16) <<
      exception_code << std::setbase(10) << " thrown in " << location << ".";
  
    return new std::string(message.GetString());
  }
  
  #endif  // GTEST_HAS_SEH
  
  namespace internal {
  
  #if GTEST_HAS_EXCEPTIONS
  
  // Adds an "exception thrown" fatal failure to the current test.
  static std::string FormatCxxExceptionMessage(const char* description,
                                               const char* location) {
    Message message;
    if (description != NULL) {
      message << "C++ exception with description \"" << description << "\"";
    } else {
      message << "Unknown C++ exception";
    }
    message << " thrown in " << location << ".";
  
    return message.GetString();
  }
  
  static std::string PrintTestPartResultToString(
      const TestPartResult& test_part_result);
  
  GoogleTestFailureException::GoogleTestFailureException(
      const TestPartResult& failure)
      : ::std::runtime_error(PrintTestPartResultToString(failure).c_str()) {}
  
  #endif  // GTEST_HAS_EXCEPTIONS
  
  // We put these helper functions in the internal namespace as IBM's xlC
  // compiler rejects the code if they were declared static.
  
  // Runs the given method and handles SEH exceptions it throws, when
  // SEH is supported; returns the 0-value for type Result in case of an
  // SEH exception.  (Microsoft compilers cannot handle SEH and C++
  // exceptions in the same function.  Therefore, we provide a separate
  // wrapper function for handling SEH exceptions.)
  template <class T, typename Result>
  Result HandleSehExceptionsInMethodIfSupported(
      T* object, Result (T::*method)(), const char* location) {
  #if GTEST_HAS_SEH
    __try {
      return (object->*method)();
    } __except (internal::UnitTestOptions::GTestShouldProcessSEH(  // NOLINT
        GetExceptionCode())) {
      // We create the exception message on the heap because VC++ prohibits
      // creation of objects with destructors on stack in functions using __try
      // (see error C2712).
      std::string* exception_message = FormatSehExceptionMessage(
          GetExceptionCode(), location);
      internal::ReportFailureInUnknownLocation(TestPartResult::kFatalFailure,
                                               *exception_message);
      delete exception_message;
      return static_cast<Result>(0);
    }
  #else
    (void)location;
    return (object->*method)();
  #endif  // GTEST_HAS_SEH
  }
  
  // Runs the given method and catches and reports C++ and/or SEH-style
  // exceptions, if they are supported; returns the 0-value for type
  // Result in case of an SEH exception.
  template <class T, typename Result>
  Result HandleExceptionsInMethodIfSupported(
      T* object, Result (T::*method)(), const char* location) {
    // NOTE: The user code can affect the way in which Google Test handles
    // exceptions by setting GTEST_FLAG(catch_exceptions), but only before
    // RUN_ALL_TESTS() starts. It is technically possible to check the flag
    // after the exception is caught and either report or re-throw the
    // exception based on the flag's value:
    //
    // try {
    //   // Perform the test method.
    // } catch (...) {
    //   if (GTEST_FLAG(catch_exceptions))
    //     // Report the exception as failure.
    //   else
    //     throw;  // Re-throws the original exception.
    // }
    //
    // However, the purpose of this flag is to allow the program to drop into
    // the debugger when the exception is thrown. On most platforms, once the
    // control enters the catch block, the exception origin information is
    // lost and the debugger will stop the program at the point of the
    // re-throw in this function -- instead of at the point of the original
    // throw statement in the code under test.  For this reason, we perform
    // the check early, sacrificing the ability to affect Google Test's
    // exception handling in the method where the exception is thrown.
    if (internal::GetUnitTestImpl()->catch_exceptions()) {
  #if GTEST_HAS_EXCEPTIONS
      try {
        return HandleSehExceptionsInMethodIfSupported(object, method, location);
      } catch (const internal::GoogleTestFailureException&) {  // NOLINT
        // This exception type can only be thrown by a failed Google
        // Test assertion with the intention of letting another testing
        // framework catch it.  Therefore we just re-throw it.
        throw;
      } catch (const std::exception& e) {  // NOLINT
        internal::ReportFailureInUnknownLocation(
            TestPartResult::kFatalFailure,
            FormatCxxExceptionMessage(e.what(), location));
      } catch (...) {  // NOLINT
        internal::ReportFailureInUnknownLocation(
            TestPartResult::kFatalFailure,
            FormatCxxExceptionMessage(NULL, location));
      }
      return static_cast<Result>(0);
  #else
      return HandleSehExceptionsInMethodIfSupported(object, method, location);
  #endif  // GTEST_HAS_EXCEPTIONS
    } else {
      return (object->*method)();
    }
  }
  
  }  // namespace internal
  
  // Runs the test and updates the test result.
  void Test::Run() {
    if (!HasSameFixtureClass()) return;
  
    internal::UnitTestImpl* const impl = internal::GetUnitTestImpl();
    impl->os_stack_trace_getter()->UponLeavingGTest();
    internal::HandleExceptionsInMethodIfSupported(this, &Test::SetUp, "SetUp()");
    // We will run the test only if SetUp() was successful.
    if (!HasFatalFailure()) {
      impl->os_stack_trace_getter()->UponLeavingGTest();
      internal::HandleExceptionsInMethodIfSupported(
          this, &Test::TestBody, "the test body");
    }
  
    // However, we want to clean up as much as possible.  Hence we will
    // always call TearDown(), even if SetUp() or the test body has
    // failed.
    impl->os_stack_trace_getter()->UponLeavingGTest();
    internal::HandleExceptionsInMethodIfSupported(
        this, &Test::TearDown, "TearDown()");
  }
  
  // Returns true iff the current test has a fatal failure.
  bool Test::HasFatalFailure() {
    return internal::GetUnitTestImpl()->current_test_result()->HasFatalFailure();
  }
  
  // Returns true iff the current test has a non-fatal failure.
  bool Test::HasNonfatalFailure() {
    return internal::GetUnitTestImpl()->current_test_result()->
        HasNonfatalFailure();
  }
  
  // class TestInfo
  
  // Constructs a TestInfo object. It assumes ownership of the test factory
  // object.
  TestInfo::TestInfo(const std::string& a_test_case_name,
                     const std::string& a_name,
                     const char* a_type_param,
                     const char* a_value_param,
                     internal::CodeLocation a_code_location,
                     internal::TypeId fixture_class_id,
                     internal::TestFactoryBase* factory)
      : test_case_name_(a_test_case_name),
        name_(a_name),
        type_param_(a_type_param ? new std::string(a_type_param) : NULL),
        value_param_(a_value_param ? new std::string(a_value_param) : NULL),
        location_(a_code_location),
        fixture_class_id_(fixture_class_id),
        should_run_(false),
        is_disabled_(false),
        matches_filter_(false),
        factory_(factory),
        result_() {}
  
  // Destructs a TestInfo object.
  TestInfo::~TestInfo() { delete factory_; }
  
  namespace internal {
  
  // Creates a new TestInfo object and registers it with Google Test;
  // returns the created object.
  //
  // Arguments:
  //
  //   test_case_name:   name of the test case
  //   name:             name of the test
  //   type_param:       the name of the test's type parameter, or NULL if
  //                     this is not a typed or a type-parameterized test.
  //   value_param:      text representation of the test's value parameter,
  //                     or NULL if this is not a value-parameterized test.
  //   code_location:    code location where the test is defined
  //   fixture_class_id: ID of the test fixture class
  //   set_up_tc:        pointer to the function that sets up the test case
  //   tear_down_tc:     pointer to the function that tears down the test case
  //   factory:          pointer to the factory that creates a test object.
  //                     The newly created TestInfo instance will assume
  //                     ownership of the factory object.
  TestInfo* MakeAndRegisterTestInfo(
      const char* test_case_name,
      const char* name,
      const char* type_param,
      const char* value_param,
      CodeLocation code_location,
      TypeId fixture_class_id,
      SetUpTestCaseFunc set_up_tc,
      TearDownTestCaseFunc tear_down_tc,
      TestFactoryBase* factory) {
    TestInfo* const test_info =
        new TestInfo(test_case_name, name, type_param, value_param,
                     code_location, fixture_class_id, factory);
    GetUnitTestImpl()->AddTestInfo(set_up_tc, tear_down_tc, test_info);
    return test_info;
  }
  
  #if GTEST_HAS_PARAM_TEST
  void ReportInvalidTestCaseType(const char* test_case_name,
                                 CodeLocation code_location) {
    Message errors;
    errors
        << "Attempted redefinition of test case " << test_case_name << ".\n"
        << "All tests in the same test case must use the same test fixture\n"
        << "class.  However, in test case " << test_case_name << ", you tried\n"
        << "to define a test using a fixture class different from the one\n"
        << "used earlier. This can happen if the two fixture classes are\n"
        << "from different namespaces and have the same name. You should\n"
        << "probably rename one of the classes to put the tests into different\n"
        << "test cases.";
  
    fprintf(stderr, "%s %s",
            FormatFileLocation(code_location.file.c_str(),
                               code_location.line).c_str(),
            errors.GetString().c_str());
  }
  #endif  // GTEST_HAS_PARAM_TEST
  
  }  // namespace internal
  
  namespace {
  
  // A predicate that checks the test name of a TestInfo against a known
  // value.
  //
  // This is used for implementation of the TestCase class only.  We put
  // it in the anonymous namespace to prevent polluting the outer
  // namespace.
  //
  // TestNameIs is copyable.
  class TestNameIs {
   public:
    // Constructor.
    //
    // TestNameIs has NO default constructor.
    explicit TestNameIs(const char* name)
        : name_(name) {}
  
    // Returns true iff the test name of test_info matches name_.
    bool operator()(const TestInfo * test_info) const {
      return test_info && test_info->name() == name_;
    }
  
   private:
    std::string name_;
  };
  
  }  // namespace
  
  namespace internal {
  
  // This method expands all parameterized tests registered with macros TEST_P
  // and INSTANTIATE_TEST_CASE_P into regular tests and registers those.
  // This will be done just once during the program runtime.
  void UnitTestImpl::RegisterParameterizedTests() {
  #if GTEST_HAS_PARAM_TEST
    if (!parameterized_tests_registered_) {
      parameterized_test_registry_.RegisterTests();
      parameterized_tests_registered_ = true;
    }
  #endif
  }
  
  }  // namespace internal
  
  // Creates the test object, runs it, records its result, and then
  // deletes it.
  void TestInfo::Run() {
    if (!should_run_) return;
  
    // Tells UnitTest where to store test result.
    internal::UnitTestImpl* const impl = internal::GetUnitTestImpl();
    impl->set_current_test_info(this);
  
    TestEventListener* repeater = UnitTest::GetInstance()->listeners().repeater();
  
    // Notifies the unit test event listeners that a test is about to start.
    repeater->OnTestStart(*this);
  
    const TimeInMillis start = internal::GetTimeInMillis();
  
    impl->os_stack_trace_getter()->UponLeavingGTest();
  
    // Creates the test object.
    Test* const test = internal::HandleExceptionsInMethodIfSupported(
        factory_, &internal::TestFactoryBase::CreateTest,
        "the test fixture's constructor");
  
    // Runs the test only if the test object was created and its
    // constructor didn't generate a fatal failure.
    if ((test != NULL) && !Test::HasFatalFailure()) {
      // This doesn't throw as all user code that can throw are wrapped into
      // exception handling code.
      test->Run();
    }
  
    // Deletes the test object.
    impl->os_stack_trace_getter()->UponLeavingGTest();
    internal::HandleExceptionsInMethodIfSupported(
        test, &Test::DeleteSelf_, "the test fixture's destructor");
  
    result_.set_elapsed_time(internal::GetTimeInMillis() - start);
  
    // Notifies the unit test event listener that a test has just finished.
    repeater->OnTestEnd(*this);
  
    // Tells UnitTest to stop associating assertion results to this
    // test.
    impl->set_current_test_info(NULL);
  }
  
  // class TestCase
  
  // Gets the number of successful tests in this test case.
  int TestCase::successful_test_count() const {
    return CountIf(test_info_list_, TestPassed);
  }
  
  // Gets the number of failed tests in this test case.
  int TestCase::failed_test_count() const {
    return CountIf(test_info_list_, TestFailed);
  }
  
  // Gets the number of disabled tests that will be reported in the XML report.
  int TestCase::reportable_disabled_test_count() const {
    return CountIf(test_info_list_, TestReportableDisabled);
  }
  
  // Gets the number of disabled tests in this test case.
  int TestCase::disabled_test_count() const {
    return CountIf(test_info_list_, TestDisabled);
  }
  
  // Gets the number of tests to be printed in the XML report.
  int TestCase::reportable_test_count() const {
    return CountIf(test_info_list_, TestReportable);
  }
  
  // Get the number of tests in this test case that should run.
  int TestCase::test_to_run_count() const {
    return CountIf(test_info_list_, ShouldRunTest);
  }
  
  // Gets the number of all tests.
  int TestCase::total_test_count() const {
    return static_cast<int>(test_info_list_.size());
  }
  
  // Creates a TestCase with the given name.
  //
  // Arguments:
  //
  //   name:         name of the test case
  //   a_type_param: the name of the test case's type parameter, or NULL if
  //                 this is not a typed or a type-parameterized test case.
  //   set_up_tc:    pointer to the function that sets up the test case
  //   tear_down_tc: pointer to the function that tears down the test case
  TestCase::TestCase(const char* a_name, const char* a_type_param,
                     Test::SetUpTestCaseFunc set_up_tc,
                     Test::TearDownTestCaseFunc tear_down_tc)
      : name_(a_name),
        type_param_(a_type_param ? new std::string(a_type_param) : NULL),
        set_up_tc_(set_up_tc),
        tear_down_tc_(tear_down_tc),
        should_run_(false),
        elapsed_time_(0) {
  }
  
  // Destructor of TestCase.
  TestCase::~TestCase() {
    // Deletes every Test in the collection.
    ForEach(test_info_list_, internal::Delete<TestInfo>);
  }
  
  // Returns the i-th test among all the tests. i can range from 0 to
  // total_test_count() - 1. If i is not in that range, returns NULL.
  const TestInfo* TestCase::GetTestInfo(int i) const {
    const int index = GetElementOr(test_indices_, i, -1);
    return index < 0 ? NULL : test_info_list_[index];
  }
  
  // Returns the i-th test among all the tests. i can range from 0 to
  // total_test_count() - 1. If i is not in that range, returns NULL.
  TestInfo* TestCase::GetMutableTestInfo(int i) {
    const int index = GetElementOr(test_indices_, i, -1);
    return index < 0 ? NULL : test_info_list_[index];
  }
  
  // Adds a test to this test case.  Will delete the test upon
  // destruction of the TestCase object.
  void TestCase::AddTestInfo(TestInfo * test_info) {
    test_info_list_.push_back(test_info);
    test_indices_.push_back(static_cast<int>(test_indices_.size()));
  }
  
  // Runs every test in this TestCase.
  void TestCase::Run() {
    if (!should_run_) return;
  
    internal::UnitTestImpl* const impl = internal::GetUnitTestImpl();
    impl->set_current_test_case(this);
  
    TestEventListener* repeater = UnitTest::GetInstance()->listeners().repeater();
  
    repeater->OnTestCaseStart(*this);
    impl->os_stack_trace_getter()->UponLeavingGTest();
    internal::HandleExceptionsInMethodIfSupported(
        this, &TestCase::RunSetUpTestCase, "SetUpTestCase()");
  
    const internal::TimeInMillis start = internal::GetTimeInMillis();
    for (int i = 0; i < total_test_count(); i++) {
      GetMutableTestInfo(i)->Run();
    }
    elapsed_time_ = internal::GetTimeInMillis() - start;
  
    impl->os_stack_trace_getter()->UponLeavingGTest();
    internal::HandleExceptionsInMethodIfSupported(
        this, &TestCase::RunTearDownTestCase, "TearDownTestCase()");
  
    repeater->OnTestCaseEnd(*this);
    impl->set_current_test_case(NULL);
  }
  
  // Clears the results of all tests in this test case.
  void TestCase::ClearResult() {
    ad_hoc_test_result_.Clear();
    ForEach(test_info_list_, TestInfo::ClearTestResult);
  }
  
  // Shuffles the tests in this test case.
  void TestCase::ShuffleTests(internal::Random* random) {
    Shuffle(random, &test_indices_);
  }
  
  // Restores the test order to before the first shuffle.
  void TestCase::UnshuffleTests() {
    for (size_t i = 0; i < test_indices_.size(); i++) {
      test_indices_[i] = static_cast<int>(i);
    }
  }
  
  // Formats a countable noun.  Depending on its quantity, either the
  // singular form or the plural form is used. e.g.
  //
  // FormatCountableNoun(1, "formula", "formuli") returns "1 formula".
  // FormatCountableNoun(5, "book", "books") returns "5 books".
  static std::string FormatCountableNoun(int count,
                                         const char * singular_form,
                                         const char * plural_form) {
    return internal::StreamableToString(count) + " " +
        (count == 1 ? singular_form : plural_form);
  }
  
  // Formats the count of tests.
  static std::string FormatTestCount(int test_count) {
    return FormatCountableNoun(test_count, "test", "tests");
  }
  
  // Formats the count of test cases.
  static std::string FormatTestCaseCount(int test_case_count) {
    return FormatCountableNoun(test_case_count, "test case", "test cases");
  }
  
  // Converts a TestPartResult::Type enum to human-friendly string
  // representation.  Both kNonFatalFailure and kFatalFailure are translated
  // to "Failure", as the user usually doesn't care about the difference
  // between the two when viewing the test result.
  static const char * TestPartResultTypeToString(TestPartResult::Type type) {
    switch (type) {
      case TestPartResult::kSuccess:
        return "Success";
  
      case TestPartResult::kNonFatalFailure:
      case TestPartResult::kFatalFailure:
  #ifdef _MSC_VER
        return "error: ";
  #else
        return "Failure\n";
  #endif
      default:
        return "Unknown result type";
    }
  }
  
  namespace internal {
  
  // Prints a TestPartResult to an std::string.
  static std::string PrintTestPartResultToString(
      const TestPartResult& test_part_result) {
    return (Message()
            << internal::FormatFileLocation(test_part_result.file_name(),
                                            test_part_result.line_number())
            << " " << TestPartResultTypeToString(test_part_result.type())
            << test_part_result.message()).GetString();
  }
  
  // Prints a TestPartResult.
  static void PrintTestPartResult(const TestPartResult& test_part_result) {
    const std::string& result =
        PrintTestPartResultToString(test_part_result);
    printf("%s\n", result.c_str());
    fflush(stdout);
    // If the test program runs in Visual Studio or a debugger, the
    // following statements add the test part result message to the Output
    // window such that the user can double-click on it to jump to the
    // corresponding source code location; otherwise they do nothing.
  #if GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE
    // We don't call OutputDebugString*() on Windows Mobile, as printing
    // to stdout is done by OutputDebugString() there already - we don't
    // want the same message printed twice.
    ::OutputDebugStringA(result.c_str());
    ::OutputDebugStringA("\n");
  #endif
  }
  
  // class PrettyUnitTestResultPrinter
  
  enum GTestColor {
    COLOR_DEFAULT,
    COLOR_RED,
    COLOR_GREEN,
    COLOR_YELLOW
  };
  
  #if GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE && \
      !GTEST_OS_WINDOWS_PHONE && !GTEST_OS_WINDOWS_RT
  
  // Returns the character attribute for the given color.
  WORD GetColorAttribute(GTestColor color) {
    switch (color) {
      case COLOR_RED:    return FOREGROUND_RED;
      case COLOR_GREEN:  return FOREGROUND_GREEN;
      case COLOR_YELLOW: return FOREGROUND_RED | FOREGROUND_GREEN;
      default:           return 0;
    }
  }
  
  #else
  
  // Returns the ANSI color code for the given color.  COLOR_DEFAULT is
  // an invalid input.
  const char* GetAnsiColorCode(GTestColor color) {
    switch (color) {
      case COLOR_RED:     return "1";
      case COLOR_GREEN:   return "2";
      case COLOR_YELLOW:  return "3";
      default:            return NULL;
    };
  }
  
  #endif  // GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE
  
  // Returns true iff Google Test should use colors in the output.
  bool ShouldUseColor(bool stdout_is_tty) {
    const char* const gtest_color = GTEST_FLAG(color).c_str();
  
    if (String::CaseInsensitiveCStringEquals(gtest_color, "auto")) {
  #if GTEST_OS_WINDOWS
      // On Windows the TERM variable is usually not set, but the
      // console there does support colors.
      return stdout_is_tty;
  #else
      // On non-Windows platforms, we rely on the TERM variable.
      const char* const term = posix::GetEnv("TERM");
      const bool term_supports_color =
          String::CStringEquals(term, "xterm") ||
          String::CStringEquals(term, "xterm-color") ||
          String::CStringEquals(term, "xterm-256color") ||
          String::CStringEquals(term, "screen") ||
          String::CStringEquals(term, "screen-256color") ||
          String::CStringEquals(term, "rxvt-unicode") ||
          String::CStringEquals(term, "rxvt-unicode-256color") ||
          String::CStringEquals(term, "linux") ||
          String::CStringEquals(term, "cygwin");
      return stdout_is_tty && term_supports_color;
  #endif  // GTEST_OS_WINDOWS
    }
  
    return String::CaseInsensitiveCStringEquals(gtest_color, "yes") ||
        String::CaseInsensitiveCStringEquals(gtest_color, "true") ||
        String::CaseInsensitiveCStringEquals(gtest_color, "t") ||
        String::CStringEquals(gtest_color, "1");
    // We take "yes", "true", "t", and "1" as meaning "yes".  If the
    // value is neither one of these nor "auto", we treat it as "no" to
    // be conservative.
  }
  
  // Helpers for printing colored strings to stdout. Note that on Windows, we
  // cannot simply emit special characters and have the terminal change colors.
  // This routine must actually emit the characters rather than return a string
  // that would be colored when printed, as can be done on Linux.
  void ColoredPrintf(GTestColor color, const char* fmt, ...) {
    va_list args;
    va_start(args, fmt);
  
  #if GTEST_OS_WINDOWS_MOBILE || GTEST_OS_SYMBIAN || GTEST_OS_ZOS || \
      GTEST_OS_IOS || GTEST_OS_WINDOWS_PHONE || GTEST_OS_WINDOWS_RT
    const bool use_color = AlwaysFalse();
  #else
    static const bool in_color_mode =
        ShouldUseColor(posix::IsATTY(posix::FileNo(stdout)) != 0);
    const bool use_color = in_color_mode && (color != COLOR_DEFAULT);
  #endif  // GTEST_OS_WINDOWS_MOBILE || GTEST_OS_SYMBIAN || GTEST_OS_ZOS
    // The '!= 0' comparison is necessary to satisfy MSVC 7.1.
  
    if (!use_color) {
      vprintf(fmt, args);
      va_end(args);
      return;
    }
  
  #if GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE && \
      !GTEST_OS_WINDOWS_PHONE && !GTEST_OS_WINDOWS_RT
    const HANDLE stdout_handle = GetStdHandle(STD_OUTPUT_HANDLE);
  
    // Gets the current text color.
    CONSOLE_SCREEN_BUFFER_INFO buffer_info;
    GetConsoleScreenBufferInfo(stdout_handle, &buffer_info);
    const WORD old_color_attrs = buffer_info.wAttributes;
  
    // We need to flush the stream buffers into the console before each
    // SetConsoleTextAttribute call lest it affect the text that is already
    // printed but has not yet reached the console.
    fflush(stdout);
    SetConsoleTextAttribute(stdout_handle,
                            GetColorAttribute(color) | FOREGROUND_INTENSITY);
    vprintf(fmt, args);
  
    fflush(stdout);
    // Restores the text color.
    SetConsoleTextAttribute(stdout_handle, old_color_attrs);
  #else
    printf("\033[0;3%sm", GetAnsiColorCode(color));
    vprintf(fmt, args);
    printf("\033[m");  // Resets the terminal to default.
  #endif  // GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE
    va_end(args);
  }
  
  // Text printed in Google Test's text output and --gunit_list_tests
  // output to label the type parameter and value parameter for a test.
  static const char kTypeParamLabel[] = "TypeParam";
  static const char kValueParamLabel[] = "GetParam()";
  
  void PrintFullTestCommentIfPresent(const TestInfo& test_info) {
    const char* const type_param = test_info.type_param();
    const char* const value_param = test_info.value_param();
  
    if (type_param != NULL || value_param != NULL) {
      printf(", where ");
      if (type_param != NULL) {
        printf("%s = %s", kTypeParamLabel, type_param);
        if (value_param != NULL)
          printf(" and ");
      }
      if (value_param != NULL) {
        printf("%s = %s", kValueParamLabel, value_param);
      }
    }
  }
  
  // This class implements the TestEventListener interface.
  //
  // Class PrettyUnitTestResultPrinter is copyable.
  class PrettyUnitTestResultPrinter : public TestEventListener {
   public:
    PrettyUnitTestResultPrinter() {}
    static void PrintTestName(const char * test_case, const char * test) {
      printf("%s.%s", test_case, test);
    }
  
    // The following methods override what's in the TestEventListener class.
    virtual void OnTestProgramStart(const UnitTest& /*unit_test*/) {}
    virtual void OnTestIterationStart(const UnitTest& unit_test, int iteration);
    virtual void OnEnvironmentsSetUpStart(const UnitTest& unit_test);
    virtual void OnEnvironmentsSetUpEnd(const UnitTest& /*unit_test*/) {}
    virtual void OnTestCaseStart(const TestCase& test_case);
    virtual void OnTestStart(const TestInfo& test_info);
    virtual void OnTestPartResult(const TestPartResult& result);
    virtual void OnTestEnd(const TestInfo& test_info);
    virtual void OnTestCaseEnd(const TestCase& test_case);
    virtual void OnEnvironmentsTearDownStart(const UnitTest& unit_test);
    virtual void OnEnvironmentsTearDownEnd(const UnitTest& /*unit_test*/) {}
    virtual void OnTestIterationEnd(const UnitTest& unit_test, int iteration);
    virtual void OnTestProgramEnd(const UnitTest& /*unit_test*/) {}
  
   private:
    static void PrintFailedTests(const UnitTest& unit_test);
  };
  
    // Fired before each iteration of tests starts.
  void PrettyUnitTestResultPrinter::OnTestIterationStart(
      const UnitTest& unit_test, int iteration) {
    if (GTEST_FLAG(repeat) != 1)
      printf("\nRepeating all tests (iteration %d) . . .\n\n", iteration + 1);
  
    const char* const filter = GTEST_FLAG(filter).c_str();
  
    // Prints the filter if it's not *.  This reminds the user that some
    // tests may be skipped.
    if (!String::CStringEquals(filter, kUniversalFilter)) {
      ColoredPrintf(COLOR_YELLOW,
                    "Note: %s filter = %s\n", GTEST_NAME_, filter);
    }
  
    if (internal::ShouldShard(kTestTotalShards, kTestShardIndex, false)) {
      const Int32 shard_index = Int32FromEnvOrDie(kTestShardIndex, -1);
      ColoredPrintf(COLOR_YELLOW,
                    "Note: This is test shard %d of %s.\n",
                    static_cast<int>(shard_index) + 1,
                    internal::posix::GetEnv(kTestTotalShards));
    }
  
    if (GTEST_FLAG(shuffle)) {
      ColoredPrintf(COLOR_YELLOW,
                    "Note: Randomizing tests' orders with a seed of %d .\n",
                    unit_test.random_seed());
    }
  
    ColoredPrintf(COLOR_GREEN,  "[==========] ");
    printf("Running %s from %s.\n",
           FormatTestCount(unit_test.test_to_run_count()).c_str(),
           FormatTestCaseCount(unit_test.test_case_to_run_count()).c_str());
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnEnvironmentsSetUpStart(
      const UnitTest& /*unit_test*/) {
    ColoredPrintf(COLOR_GREEN,  "[----------] ");
    printf("Global test environment set-up.\n");
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnTestCaseStart(const TestCase& test_case) {
    const std::string counts =
        FormatCountableNoun(test_case.test_to_run_count(), "test", "tests");
    ColoredPrintf(COLOR_GREEN, "[----------] ");
    printf("%s from %s", counts.c_str(), test_case.name());
    if (test_case.type_param() == NULL) {
      printf("\n");
    } else {
      printf(", where %s = %s\n", kTypeParamLabel, test_case.type_param());
    }
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnTestStart(const TestInfo& test_info) {
    ColoredPrintf(COLOR_GREEN,  "[ RUN      ] ");
    PrintTestName(test_info.test_case_name(), test_info.name());
    printf("\n");
    fflush(stdout);
  }
  
  // Called after an assertion failure.
  void PrettyUnitTestResultPrinter::OnTestPartResult(
      const TestPartResult& result) {
    // If the test part succeeded, we don't need to do anything.
    if (result.type() == TestPartResult::kSuccess)
      return;
  
    // Print failure message from the assertion (e.g. expected this and got that).
    PrintTestPartResult(result);
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnTestEnd(const TestInfo& test_info) {
    if (test_info.result()->Passed()) {
      ColoredPrintf(COLOR_GREEN, "[       OK ] ");
    } else {
      ColoredPrintf(COLOR_RED, "[  FAILED  ] ");
    }
    PrintTestName(test_info.test_case_name(), test_info.name());
    if (test_info.result()->Failed())
      PrintFullTestCommentIfPresent(test_info);
  
    if (GTEST_FLAG(print_time)) {
      printf(" (%s ms)\n", internal::StreamableToString(
             test_info.result()->elapsed_time()).c_str());
    } else {
      printf("\n");
    }
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnTestCaseEnd(const TestCase& test_case) {
    if (!GTEST_FLAG(print_time)) return;
  
    const std::string counts =
        FormatCountableNoun(test_case.test_to_run_count(), "test", "tests");
    ColoredPrintf(COLOR_GREEN, "[----------] ");
    printf("%s from %s (%s ms total)\n\n",
           counts.c_str(), test_case.name(),
           internal::StreamableToString(test_case.elapsed_time()).c_str());
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnEnvironmentsTearDownStart(
      const UnitTest& /*unit_test*/) {
    ColoredPrintf(COLOR_GREEN,  "[----------] ");
    printf("Global test environment tear-down\n");
    fflush(stdout);
  }
  
  // Internal helper for printing the list of failed tests.
  void PrettyUnitTestResultPrinter::PrintFailedTests(const UnitTest& unit_test) {
    const int failed_test_count = unit_test.failed_test_count();
    if (failed_test_count == 0) {
      return;
    }
  
    for (int i = 0; i < unit_test.total_test_case_count(); ++i) {
      const TestCase& test_case = *unit_test.GetTestCase(i);
      if (!test_case.should_run() || (test_case.failed_test_count() == 0)) {
        continue;
      }
      for (int j = 0; j < test_case.total_test_count(); ++j) {
        const TestInfo& test_info = *test_case.GetTestInfo(j);
        if (!test_info.should_run() || test_info.result()->Passed()) {
          continue;
        }
        ColoredPrintf(COLOR_RED, "[  FAILED  ] ");
        printf("%s.%s", test_case.name(), test_info.name());
        PrintFullTestCommentIfPresent(test_info);
        printf("\n");
      }
    }
  }
  
  void PrettyUnitTestResultPrinter::OnTestIterationEnd(const UnitTest& unit_test,
                                                       int /*iteration*/) {
    ColoredPrintf(COLOR_GREEN,  "[==========] ");
    printf("%s from %s ran.",
           FormatTestCount(unit_test.test_to_run_count()).c_str(),
           FormatTestCaseCount(unit_test.test_case_to_run_count()).c_str());
    if (GTEST_FLAG(print_time)) {
      printf(" (%s ms total)",
             internal::StreamableToString(unit_test.elapsed_time()).c_str());
    }
    printf("\n");
    ColoredPrintf(COLOR_GREEN,  "[  PASSED  ] ");
    printf("%s.\n", FormatTestCount(unit_test.successful_test_count()).c_str());
  
    int num_failures = unit_test.failed_test_count();
    if (!unit_test.Passed()) {
      const int failed_test_count = unit_test.failed_test_count();
      ColoredPrintf(COLOR_RED,  "[  FAILED  ] ");
      printf("%s, listed below:\n", FormatTestCount(failed_test_count).c_str());
      PrintFailedTests(unit_test);
      printf("\n%2d FAILED %s\n", num_failures,
                          num_failures == 1 ? "TEST" : "TESTS");
    }
  
    int num_disabled = unit_test.reportable_disabled_test_count();
    if (num_disabled && !GTEST_FLAG(also_run_disabled_tests)) {
      if (!num_failures) {
        printf("\n");  // Add a spacer if no FAILURE banner is displayed.
      }
      ColoredPrintf(COLOR_YELLOW,
                    "  YOU HAVE %d DISABLED %s\n\n",
                    num_disabled,
                    num_disabled == 1 ? "TEST" : "TESTS");
    }
    // Ensure that Google Test output is printed before, e.g., heapchecker output.
    fflush(stdout);
  }
  
  // End PrettyUnitTestResultPrinter
  
  // class TestEventRepeater
  //
  // This class forwards events to other event listeners.
  class TestEventRepeater : public TestEventListener {
   public:
    TestEventRepeater() : forwarding_enabled_(true) {}
    virtual ~TestEventRepeater();
    void Append(TestEventListener *listener);
    TestEventListener* Release(TestEventListener* listener);
  
    // Controls whether events will be forwarded to listeners_. Set to false
    // in death test child processes.
    bool forwarding_enabled() const { return forwarding_enabled_; }
    void set_forwarding_enabled(bool enable) { forwarding_enabled_ = enable; }
  
    virtual void OnTestProgramStart(const UnitTest& unit_test);
    virtual void OnTestIterationStart(const UnitTest& unit_test, int iteration);
    virtual void OnEnvironmentsSetUpStart(const UnitTest& unit_test);
    virtual void OnEnvironmentsSetUpEnd(const UnitTest& unit_test);
    virtual void OnTestCaseStart(const TestCase& test_case);
    virtual void OnTestStart(const TestInfo& test_info);
    virtual void OnTestPartResult(const TestPartResult& result);
    virtual void OnTestEnd(const TestInfo& test_info);
    virtual void OnTestCaseEnd(const TestCase& test_case);
    virtual void OnEnvironmentsTearDownStart(const UnitTest& unit_test);
    virtual void OnEnvironmentsTearDownEnd(const UnitTest& unit_test);
    virtual void OnTestIterationEnd(const UnitTest& unit_test, int iteration);
    virtual void OnTestProgramEnd(const UnitTest& unit_test);
  
   private:
    // Controls whether events will be forwarded to listeners_. Set to false
    // in death test child processes.
    bool forwarding_enabled_;
    // The list of listeners that receive events.
    std::vector<TestEventListener*> listeners_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(TestEventRepeater);
  };
  
  TestEventRepeater::~TestEventRepeater() {
    ForEach(listeners_, Delete<TestEventListener>);
  }
  
  void TestEventRepeater::Append(TestEventListener *listener) {
    listeners_.push_back(listener);
  }
  
  // TODO(vladl@google.com): Factor the search functionality into Vector::Find.
  TestEventListener* TestEventRepeater::Release(TestEventListener *listener) {
    for (size_t i = 0; i < listeners_.size(); ++i) {
      if (listeners_[i] == listener) {
        listeners_.erase(listeners_.begin() + i);
        return listener;
      }
    }
  
    return NULL;
  }
  
  // Since most methods are very similar, use macros to reduce boilerplate.
  // This defines a member that forwards the call to all listeners.
  #define GTEST_REPEATER_METHOD_(Name, Type) \
  void TestEventRepeater::Name(const Type& parameter) { \
    if (forwarding_enabled_) { \
      for (size_t i = 0; i < listeners_.size(); i++) { \
        listeners_[i]->Name(parameter); \
      } \
    } \
  }
  // This defines a member that forwards the call to all listeners in reverse
  // order.
  #define GTEST_REVERSE_REPEATER_METHOD_(Name, Type) \
  void TestEventRepeater::Name(const Type& parameter) { \
    if (forwarding_enabled_) { \
      for (int i = static_cast<int>(listeners_.size()) - 1; i >= 0; i--) { \
        listeners_[i]->Name(parameter); \
      } \
    } \
  }
  
  GTEST_REPEATER_METHOD_(OnTestProgramStart, UnitTest)
  GTEST_REPEATER_METHOD_(OnEnvironmentsSetUpStart, UnitTest)
  GTEST_REPEATER_METHOD_(OnTestCaseStart, TestCase)
  GTEST_REPEATER_METHOD_(OnTestStart, TestInfo)
  GTEST_REPEATER_METHOD_(OnTestPartResult, TestPartResult)
  GTEST_REPEATER_METHOD_(OnEnvironmentsTearDownStart, UnitTest)
  GTEST_REVERSE_REPEATER_METHOD_(OnEnvironmentsSetUpEnd, UnitTest)
  GTEST_REVERSE_REPEATER_METHOD_(OnEnvironmentsTearDownEnd, UnitTest)
  GTEST_REVERSE_REPEATER_METHOD_(OnTestEnd, TestInfo)
  GTEST_REVERSE_REPEATER_METHOD_(OnTestCaseEnd, TestCase)
  GTEST_REVERSE_REPEATER_METHOD_(OnTestProgramEnd, UnitTest)
  
  #undef GTEST_REPEATER_METHOD_
  #undef GTEST_REVERSE_REPEATER_METHOD_
  
  void TestEventRepeater::OnTestIterationStart(const UnitTest& unit_test,
                                               int iteration) {
    if (forwarding_enabled_) {
      for (size_t i = 0; i < listeners_.size(); i++) {
        listeners_[i]->OnTestIterationStart(unit_test, iteration);
      }
    }
  }
  
  void TestEventRepeater::OnTestIterationEnd(const UnitTest& unit_test,
                                             int iteration) {
    if (forwarding_enabled_) {
      for (int i = static_cast<int>(listeners_.size()) - 1; i >= 0; i--) {
        listeners_[i]->OnTestIterationEnd(unit_test, iteration);
      }
    }
  }
  
  // End TestEventRepeater
  
  // This class generates an XML output file.
  class XmlUnitTestResultPrinter : public EmptyTestEventListener {
   public:
    explicit XmlUnitTestResultPrinter(const char* output_file);
  
    virtual void OnTestIterationEnd(const UnitTest& unit_test, int iteration);
  
   private:
    // Is c a whitespace character that is normalized to a space character
    // when it appears in an XML attribute value?
    static bool IsNormalizableWhitespace(char c) {
      return c == 0x9 || c == 0xA || c == 0xD;
    }
  
    // May c appear in a well-formed XML document?
    static bool IsValidXmlCharacter(char c) {
      return IsNormalizableWhitespace(c) || c >= 0x20;
    }
  
    // Returns an XML-escaped copy of the input string str.  If
    // is_attribute is true, the text is meant to appear as an attribute
    // value, and normalizable whitespace is preserved by replacing it
    // with character references.
    static std::string EscapeXml(const std::string& str, bool is_attribute);
  
    // Returns the given string with all characters invalid in XML removed.
    static std::string RemoveInvalidXmlCharacters(const std::string& str);
  
    // Convenience wrapper around EscapeXml when str is an attribute value.
    static std::string EscapeXmlAttribute(const std::string& str) {
      return EscapeXml(str, true);
    }
  
    // Convenience wrapper around EscapeXml when str is not an attribute value.
    static std::string EscapeXmlText(const char* str) {
      return EscapeXml(str, false);
    }
  
    // Verifies that the given attribute belongs to the given element and
    // streams the attribute as XML.
    static void OutputXmlAttribute(std::ostream* stream,
                                   const std::string& element_name,
                                   const std::string& name,
                                   const std::string& value);
  
    // Streams an XML CDATA section, escaping invalid CDATA sequences as needed.
    static void OutputXmlCDataSection(::std::ostream* stream, const char* data);
  
    // Streams an XML representation of a TestInfo object.
    static void OutputXmlTestInfo(::std::ostream* stream,
                                  const char* test_case_name,
                                  const TestInfo& test_info);
  
    // Prints an XML representation of a TestCase object
    static void PrintXmlTestCase(::std::ostream* stream,
                                 const TestCase& test_case);
  
    // Prints an XML summary of unit_test to output stream out.
    static void PrintXmlUnitTest(::std::ostream* stream,
                                 const UnitTest& unit_test);
  
    // Produces a string representing the test properties in a result as space
    // delimited XML attributes based on the property key="value" pairs.
    // When the std::string is not empty, it includes a space at the beginning,
    // to delimit this attribute from prior attributes.
    static std::string TestPropertiesAsXmlAttributes(const TestResult& result);
  
    // The output file.
    const std::string output_file_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(XmlUnitTestResultPrinter);
  };
  
  // Creates a new XmlUnitTestResultPrinter.
  XmlUnitTestResultPrinter::XmlUnitTestResultPrinter(const char* output_file)
      : output_file_(output_file) {
    if (output_file_.c_str() == NULL || output_file_.empty()) {
      fprintf(stderr, "XML output file may not be null\n");
      fflush(stderr);
      exit(EXIT_FAILURE);
    }
  }
  
  // Called after the unit test ends.
  void XmlUnitTestResultPrinter::OnTestIterationEnd(const UnitTest& unit_test,
                                                    int /*iteration*/) {
    FILE* xmlout = NULL;
    FilePath output_file(output_file_);
    FilePath output_dir(output_file.RemoveFileName());
  
    if (output_dir.CreateDirectoriesRecursively()) {
      xmlout = posix::FOpen(output_file_.c_str(), "w");
    }
    if (xmlout == NULL) {
      // TODO(wan): report the reason of the failure.
      //
      // We don't do it for now as:
      //
      //   1. There is no urgent need for it.
      //   2. It's a bit involved to make the errno variable thread-safe on
      //      all three operating systems (Linux, Windows, and Mac OS).
      //   3. To interpret the meaning of errno in a thread-safe way,
      //      we need the strerror_r() function, which is not available on
      //      Windows.
      fprintf(stderr,
              "Unable to open file \"%s\"\n",
              output_file_.c_str());
      fflush(stderr);
      exit(EXIT_FAILURE);
    }
    std::stringstream stream;
    PrintXmlUnitTest(&stream, unit_test);
    fprintf(xmlout, "%s", StringStreamToString(&stream).c_str());
    fclose(xmlout);
  }
  
  // Returns an XML-escaped copy of the input string str.  If is_attribute
  // is true, the text is meant to appear as an attribute value, and
  // normalizable whitespace is preserved by replacing it with character
  // references.
  //
  // Invalid XML characters in str, if any, are stripped from the output.
  // It is expected that most, if not all, of the text processed by this
  // module will consist of ordinary English text.
  // If this module is ever modified to produce version 1.1 XML output,
  // most invalid characters can be retained using character references.
  // TODO(wan): It might be nice to have a minimally invasive, human-readable
  // escaping scheme for invalid characters, rather than dropping them.
  std::string XmlUnitTestResultPrinter::EscapeXml(
      const std::string& str, bool is_attribute) {
    Message m;
  
    for (size_t i = 0; i < str.size(); ++i) {
      const char ch = str[i];
      switch (ch) {
        case '<':
          m << "&lt;";
          break;
        case '>':
          m << "&gt;";
          break;
        case '&':
          m << "&amp;";
          break;
        case '\'':
          if (is_attribute)
            m << "&apos;";
          else
            m << '\'';
          break;
        case '"':
          if (is_attribute)
            m << "&quot;";
          else
            m << '"';
          break;
        default:
          if (IsValidXmlCharacter(ch)) {
            if (is_attribute && IsNormalizableWhitespace(ch))
              m << "&#x" << String::FormatByte(static_cast<unsigned char>(ch))
                << ";";
            else
              m << ch;
          }
          break;
      }
    }
  
    return m.GetString();
  }
  
  // Returns the given string with all characters invalid in XML removed.
  // Currently invalid characters are dropped from the string. An
  // alternative is to replace them with certain characters such as . or ?.
  std::string XmlUnitTestResultPrinter::RemoveInvalidXmlCharacters(
      const std::string& str) {
    std::string output;
    output.reserve(str.size());
    for (std::string::const_iterator it = str.begin(); it != str.end(); ++it)
      if (IsValidXmlCharacter(*it))
        output.push_back(*it);
  
    return output;
  }
  
  // The following routines generate an XML representation of a UnitTest
  // object.
  //
  // This is how Google Test concepts map to the DTD:
  //
  // <testsuites name="AllTests">        <-- corresponds to a UnitTest object
  //   <testsuite name="testcase-name">  <-- corresponds to a TestCase object
  //     <testcase name="test-name">     <-- corresponds to a TestInfo object
  //       <failure message="...">...</failure>
  //       <failure message="...">...</failure>
  //       <failure message="...">...</failure>
  //                                     <-- individual assertion failures
  //     </testcase>
  //   </testsuite>
  // </testsuites>
  
  // Formats the given time in milliseconds as seconds.
  std::string FormatTimeInMillisAsSeconds(TimeInMillis ms) {
    ::std::stringstream ss;
    ss << (static_cast<double>(ms) * 1e-3);
    return ss.str();
  }
  
  static bool PortableLocaltime(time_t seconds, struct tm* out) {
  #if defined(_MSC_VER)
    return localtime_s(out, &seconds) == 0;
  #elif defined(__MINGW32__) || defined(__MINGW64__)
    // MINGW <time.h> provides neither localtime_r nor localtime_s, but uses
    // Windows' localtime(), which has a thread-local tm buffer.
    struct tm* tm_ptr = localtime(&seconds);  // NOLINT
    if (tm_ptr == NULL)
      return false;
    *out = *tm_ptr;
    return true;
  #else
    return localtime_r(&seconds, out) != NULL;
  #endif
  }
  
  // Converts the given epoch time in milliseconds to a date string in the ISO
  // 8601 format, without the timezone information.
  std::string FormatEpochTimeInMillisAsIso8601(TimeInMillis ms) {
    struct tm time_struct;
    if (!PortableLocaltime(static_cast<time_t>(ms / 1000), &time_struct))
      return "";
    // YYYY-MM-DDThh:mm:ss
    return StreamableToString(time_struct.tm_year + 1900) + "-" +
        String::FormatIntWidth2(time_struct.tm_mon + 1) + "-" +
        String::FormatIntWidth2(time_struct.tm_mday) + "T" +
        String::FormatIntWidth2(time_struct.tm_hour) + ":" +
        String::FormatIntWidth2(time_struct.tm_min) + ":" +
        String::FormatIntWidth2(time_struct.tm_sec);
  }
  
  // Streams an XML CDATA section, escaping invalid CDATA sequences as needed.
  void XmlUnitTestResultPrinter::OutputXmlCDataSection(::std::ostream* stream,
                                                       const char* data) {
    const char* segment = data;
    *stream << "<![CDATA[";
    for (;;) {
      const char* const next_segment = strstr(segment, "]]>");
      if (next_segment != NULL) {
        stream->write(
            segment, static_cast<std::streamsize>(next_segment - segment));
        *stream << "]]>]]&gt;<![CDATA[";
        segment = next_segment + strlen("]]>");
      } else {
        *stream << segment;
        break;
      }
    }
    *stream << "]]>";
  }
  
  void XmlUnitTestResultPrinter::OutputXmlAttribute(
      std::ostream* stream,
      const std::string& element_name,
      const std::string& name,
      const std::string& value) {
    const std::vector<std::string>& allowed_names =
        GetReservedAttributesForElement(element_name);
  
    GTEST_CHECK_(std::find(allowed_names.begin(), allowed_names.end(), name) !=
                     allowed_names.end())
        << "Attribute " << name << " is not allowed for element <" << element_name
        << ">.";
  
    *stream << " " << name << "=\"" << EscapeXmlAttribute(value) << "\"";
  }
  
  // Prints an XML representation of a TestInfo object.
  // TODO(wan): There is also value in printing properties with the plain printer.
  void XmlUnitTestResultPrinter::OutputXmlTestInfo(::std::ostream* stream,
                                                   const char* test_case_name,
                                                   const TestInfo& test_info) {
    const TestResult& result = *test_info.result();
    const std::string kTestcase = "testcase";
  
    *stream << "    <testcase";
    OutputXmlAttribute(stream, kTestcase, "name", test_info.name());
  
    if (test_info.value_param() != NULL) {
      OutputXmlAttribute(stream, kTestcase, "value_param",
                         test_info.value_param());
    }
    if (test_info.type_param() != NULL) {
      OutputXmlAttribute(stream, kTestcase, "type_param", test_info.type_param());
    }
  
    OutputXmlAttribute(stream, kTestcase, "status",
                       test_info.should_run() ? "run" : "notrun");
    OutputXmlAttribute(stream, kTestcase, "time",
                       FormatTimeInMillisAsSeconds(result.elapsed_time()));
    OutputXmlAttribute(stream, kTestcase, "classname", test_case_name);
    *stream << TestPropertiesAsXmlAttributes(result);
  
    int failures = 0;
    for (int i = 0; i < result.total_part_count(); ++i) {
      const TestPartResult& part = result.GetTestPartResult(i);
      if (part.failed()) {
        if (++failures == 1) {
          *stream << ">\n";
        }
        const string location = internal::FormatCompilerIndependentFileLocation(
            part.file_name(), part.line_number());
        const string summary = location + "\n" + part.summary();
        *stream << "      <failure message=\""
                << EscapeXmlAttribute(summary.c_str())
                << "\" type=\"\">";
        const string detail = location + "\n" + part.message();
        OutputXmlCDataSection(stream, RemoveInvalidXmlCharacters(detail).c_str());
        *stream << "</failure>\n";
      }
    }
  
    if (failures == 0)
      *stream << " />\n";
    else
      *stream << "    </testcase>\n";
  }
  
  // Prints an XML representation of a TestCase object
  void XmlUnitTestResultPrinter::PrintXmlTestCase(std::ostream* stream,
                                                  const TestCase& test_case) {
    const std::string kTestsuite = "testsuite";
    *stream << "  <" << kTestsuite;
    OutputXmlAttribute(stream, kTestsuite, "name", test_case.name());
    OutputXmlAttribute(stream, kTestsuite, "tests",
                       StreamableToString(test_case.reportable_test_count()));
    OutputXmlAttribute(stream, kTestsuite, "failures",
                       StreamableToString(test_case.failed_test_count()));
    OutputXmlAttribute(
        stream, kTestsuite, "disabled",
        StreamableToString(test_case.reportable_disabled_test_count()));
    OutputXmlAttribute(stream, kTestsuite, "errors", "0");
    OutputXmlAttribute(stream, kTestsuite, "time",
                       FormatTimeInMillisAsSeconds(test_case.elapsed_time()));
    *stream << TestPropertiesAsXmlAttributes(test_case.ad_hoc_test_result())
            << ">\n";
  
    for (int i = 0; i < test_case.total_test_count(); ++i) {
      if (test_case.GetTestInfo(i)->is_reportable())
        OutputXmlTestInfo(stream, test_case.name(), *test_case.GetTestInfo(i));
    }
    *stream << "  </" << kTestsuite << ">\n";
  }
  
  // Prints an XML summary of unit_test to output stream out.
  void XmlUnitTestResultPrinter::PrintXmlUnitTest(std::ostream* stream,
                                                  const UnitTest& unit_test) {
    const std::string kTestsuites = "testsuites";
  
    *stream << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";
    *stream << "<" << kTestsuites;
  
    OutputXmlAttribute(stream, kTestsuites, "tests",
                       StreamableToString(unit_test.reportable_test_count()));
    OutputXmlAttribute(stream, kTestsuites, "failures",
                       StreamableToString(unit_test.failed_test_count()));
    OutputXmlAttribute(
        stream, kTestsuites, "disabled",
        StreamableToString(unit_test.reportable_disabled_test_count()));
    OutputXmlAttribute(stream, kTestsuites, "errors", "0");
    OutputXmlAttribute(
        stream, kTestsuites, "timestamp",
        FormatEpochTimeInMillisAsIso8601(unit_test.start_timestamp()));
    OutputXmlAttribute(stream, kTestsuites, "time",
                       FormatTimeInMillisAsSeconds(unit_test.elapsed_time()));
  
    if (GTEST_FLAG(shuffle)) {
      OutputXmlAttribute(stream, kTestsuites, "random_seed",
                         StreamableToString(unit_test.random_seed()));
    }
  
    *stream << TestPropertiesAsXmlAttributes(unit_test.ad_hoc_test_result());
  
    OutputXmlAttribute(stream, kTestsuites, "name", "AllTests");
    *stream << ">\n";
  
    for (int i = 0; i < unit_test.total_test_case_count(); ++i) {
      if (unit_test.GetTestCase(i)->reportable_test_count() > 0)
        PrintXmlTestCase(stream, *unit_test.GetTestCase(i));
    }
    *stream << "</" << kTestsuites << ">\n";
  }
  
  // Produces a string representing the test properties in a result as space
  // delimited XML attributes based on the property key="value" pairs.
  std::string XmlUnitTestResultPrinter::TestPropertiesAsXmlAttributes(
      const TestResult& result) {
    Message attributes;
    for (int i = 0; i < result.test_property_count(); ++i) {
      const TestProperty& property = result.GetTestProperty(i);
      attributes << " " << property.key() << "="
          << "\"" << EscapeXmlAttribute(property.value()) << "\"";
    }
    return attributes.GetString();
  }
  
  // End XmlUnitTestResultPrinter
  
  #if GTEST_CAN_STREAM_RESULTS_
  
  // Checks if str contains '=', '&', '%' or '\n' characters. If yes,
  // replaces them by "%xx" where xx is their hexadecimal value. For
  // example, replaces "=" with "%3D".  This algorithm is O(strlen(str))
  // in both time and space -- important as the input str may contain an
  // arbitrarily long test failure message and stack trace.
  string StreamingListener::UrlEncode(const char* str) {
    string result;
    result.reserve(strlen(str) + 1);
    for (char ch = *str; ch != '\0'; ch = *++str) {
      switch (ch) {
        case '%':
        case '=':
        case '&':
        case '\n':
          result.append("%" + String::FormatByte(static_cast<unsigned char>(ch)));
          break;
        default:
          result.push_back(ch);
          break;
      }
    }
    return result;
  }
  
  void StreamingListener::SocketWriter::MakeConnection() {
    GTEST_CHECK_(sockfd_ == -1)
        << "MakeConnection() can't be called when there is already a connection.";
  
    addrinfo hints;
    memset(&hints, 0, sizeof(hints));
    hints.ai_family = AF_UNSPEC;    // To allow both IPv4 and IPv6 addresses.
    hints.ai_socktype = SOCK_STREAM;
    addrinfo* servinfo = NULL;
  
    // Use the getaddrinfo() to get a linked list of IP addresses for
    // the given host name.
    const int error_num = getaddrinfo(
        host_name_.c_str(), port_num_.c_str(), &hints, &servinfo);
    if (error_num != 0) {
      GTEST_LOG_(WARNING) << "stream_result_to: getaddrinfo() failed: "
                          << gai_strerror(error_num);
    }
  
    // Loop through all the results and connect to the first we can.
    for (addrinfo* cur_addr = servinfo; sockfd_ == -1 && cur_addr != NULL;
         cur_addr = cur_addr->ai_next) {
      sockfd_ = socket(
          cur_addr->ai_family, cur_addr->ai_socktype, cur_addr->ai_protocol);
      if (sockfd_ != -1) {
        // Connect the client socket to the server socket.
        if (connect(sockfd_, cur_addr->ai_addr, cur_addr->ai_addrlen) == -1) {
          close(sockfd_);
          sockfd_ = -1;
        }
      }
    }
  
    freeaddrinfo(servinfo);  // all done with this structure
  
    if (sockfd_ == -1) {
      GTEST_LOG_(WARNING) << "stream_result_to: failed to connect to "
                          << host_name_ << ":" << port_num_;
    }
  }
  
  // End of class Streaming Listener
  #endif  // GTEST_CAN_STREAM_RESULTS__
  
  // Class ScopedTrace
  
  // Pushes the given source file location and message onto a per-thread
  // trace stack maintained by Google Test.
  ScopedTrace::ScopedTrace(const char* file, int line, const Message& message)
      GTEST_LOCK_EXCLUDED_(&UnitTest::mutex_) {
    TraceInfo trace;
    trace.file = file;
    trace.line = line;
    trace.message = message.GetString();
  
    UnitTest::GetInstance()->PushGTestTrace(trace);
  }
  
  // Pops the info pushed by the c'tor.
  ScopedTrace::~ScopedTrace()
      GTEST_LOCK_EXCLUDED_(&UnitTest::mutex_) {
    UnitTest::GetInstance()->PopGTestTrace();
  }
  
  
  // class OsStackTraceGetter
  
  const char* const OsStackTraceGetterInterface::kElidedFramesMarker =
      "... " GTEST_NAME_ " internal frames ...";
  
  string OsStackTraceGetter::CurrentStackTrace(int /*max_depth*/,
                                               int /*skip_count*/) {
    return "";
  }
  
  void OsStackTraceGetter::UponLeavingGTest() {}
  
  // A helper class that creates the premature-exit file in its
  // constructor and deletes the file in its destructor.
  class ScopedPrematureExitFile {
   public:
    explicit ScopedPrematureExitFile(const char* premature_exit_filepath)
        : premature_exit_filepath_(premature_exit_filepath) {
      // If a path to the premature-exit file is specified...
      if (premature_exit_filepath != NULL && *premature_exit_filepath != '\0') {
        // create the file with a single "0" character in it.  I/O
        // errors are ignored as there's nothing better we can do and we
        // don't want to fail the test because of this.
        FILE* pfile = posix::FOpen(premature_exit_filepath, "w");
        fwrite("0", 1, 1, pfile);
        fclose(pfile);
      }
    }
  
    ~ScopedPrematureExitFile() {
      if (premature_exit_filepath_ != NULL && *premature_exit_filepath_ != '\0') {
        remove(premature_exit_filepath_);
      }
    }
  
   private:
    const char* const premature_exit_filepath_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(ScopedPrematureExitFile);
  };
  
  }  // namespace internal
  
  // class TestEventListeners
  
  TestEventListeners::TestEventListeners()
      : repeater_(new internal::TestEventRepeater()),
        default_result_printer_(NULL),
        default_xml_generator_(NULL) {
  }
  
  TestEventListeners::~TestEventListeners() { delete repeater_; }
  
  // Returns the standard listener responsible for the default console
  // output.  Can be removed from the listeners list to shut down default
  // console output.  Note that removing this object from the listener list
  // with Release transfers its ownership to the user.
  void TestEventListeners::Append(TestEventListener* listener) {
    repeater_->Append(listener);
  }
  
  // Removes the given event listener from the list and returns it.  It then
  // becomes the caller's responsibility to delete the listener. Returns
  // NULL if the listener is not found in the list.
  TestEventListener* TestEventListeners::Release(TestEventListener* listener) {
    if (listener == default_result_printer_)
      default_result_printer_ = NULL;
    else if (listener == default_xml_generator_)
      default_xml_generator_ = NULL;
    return repeater_->Release(listener);
  }
  
  // Returns repeater that broadcasts the TestEventListener events to all
  // subscribers.
  TestEventListener* TestEventListeners::repeater() { return repeater_; }
  
  // Sets the default_result_printer attribute to the provided listener.
  // The listener is also added to the listener list and previous
  // default_result_printer is removed from it and deleted. The listener can
  // also be NULL in which case it will not be added to the list. Does
  // nothing if the previous and the current listener objects are the same.
  void TestEventListeners::SetDefaultResultPrinter(TestEventListener* listener) {
    if (default_result_printer_ != listener) {
      // It is an error to pass this method a listener that is already in the
      // list.
      delete Release(default_result_printer_);
      default_result_printer_ = listener;
      if (listener != NULL)
        Append(listener);
    }
  }
  
  // Sets the default_xml_generator attribute to the provided listener.  The
  // listener is also added to the listener list and previous
  // default_xml_generator is removed from it and deleted. The listener can
  // also be NULL in which case it will not be added to the list. Does
  // nothing if the previous and the current listener objects are the same.
  void TestEventListeners::SetDefaultXmlGenerator(TestEventListener* listener) {
    if (default_xml_generator_ != listener) {
      // It is an error to pass this method a listener that is already in the
      // list.
      delete Release(default_xml_generator_);
      default_xml_generator_ = listener;
      if (listener != NULL)
        Append(listener);
    }
  }
  
  // Controls whether events will be forwarded by the repeater to the
  // listeners in the list.
  bool TestEventListeners::EventForwardingEnabled() const {
    return repeater_->forwarding_enabled();
  }
  
  void TestEventListeners::SuppressEventForwarding() {
    repeater_->set_forwarding_enabled(false);
  }
  
  // class UnitTest
  
  // Gets the singleton UnitTest object.  The first time this method is
  // called, a UnitTest object is constructed and returned.  Consecutive
  // calls will return the same object.
  //
  // We don't protect this under mutex_ as a user is not supposed to
  // call this before main() starts, from which point on the return
  // value will never change.
  UnitTest* UnitTest::GetInstance() {
    // When compiled with MSVC 7.1 in optimized mode, destroying the
    // UnitTest object upon exiting the program messes up the exit code,
    // causing successful tests to appear failed.  We have to use a
    // different implementation in this case to bypass the compiler bug.
    // This implementation makes the compiler happy, at the cost of
    // leaking the UnitTest object.
  
    // CodeGear C++Builder insists on a public destructor for the
    // default implementation.  Use this implementation to keep good OO
    // design with private destructor.
  
  #if (_MSC_VER == 1310 && !defined(_DEBUG)) || defined(__BORLANDC__)
    static UnitTest* const instance = new UnitTest;
    return instance;
  #else
    static UnitTest instance;
    return &instance;
  #endif  // (_MSC_VER == 1310 && !defined(_DEBUG)) || defined(__BORLANDC__)
  }
  
  // Gets the number of successful test cases.
  int UnitTest::successful_test_case_count() const {
    return impl()->successful_test_case_count();
  }
  
  // Gets the number of failed test cases.
  int UnitTest::failed_test_case_count() const {
    return impl()->failed_test_case_count();
  }
  
  // Gets the number of all test cases.
  int UnitTest::total_test_case_count() const {
    return impl()->total_test_case_count();
  }
  
  // Gets the number of all test cases that contain at least one test
  // that should run.
  int UnitTest::test_case_to_run_count() const {
    return impl()->test_case_to_run_count();
  }
  
  // Gets the number of successful tests.
  int UnitTest::successful_test_count() const {
    return impl()->successful_test_count();
  }
  
  // Gets the number of failed tests.
  int UnitTest::failed_test_count() const { return impl()->failed_test_count(); }
  
  // Gets the number of disabled tests that will be reported in the XML report.
  int UnitTest::reportable_disabled_test_count() const {
    return impl()->reportable_disabled_test_count();
  }
  
  // Gets the number of disabled tests.
  int UnitTest::disabled_test_count() const {
    return impl()->disabled_test_count();
  }
  
  // Gets the number of tests to be printed in the XML report.
  int UnitTest::reportable_test_count() const {
    return impl()->reportable_test_count();
  }
  
  // Gets the number of all tests.
  int UnitTest::total_test_count() const { return impl()->total_test_count(); }
  
  // Gets the number of tests that should run.
  int UnitTest::test_to_run_count() const { return impl()->test_to_run_count(); }
  
  // Gets the time of the test program start, in ms from the start of the
  // UNIX epoch.
  internal::TimeInMillis UnitTest::start_timestamp() const {
      return impl()->start_timestamp();
  }
  
  // Gets the elapsed time, in milliseconds.
  internal::TimeInMillis UnitTest::elapsed_time() const {
    return impl()->elapsed_time();
  }
  
  // Returns true iff the unit test passed (i.e. all test cases passed).
  bool UnitTest::Passed() const { return impl()->Passed(); }
  
  // Returns true iff the unit test failed (i.e. some test case failed
  // or something outside of all tests failed).
  bool UnitTest::Failed() const { return impl()->Failed(); }
  
  // Gets the i-th test case among all the test cases. i can range from 0 to
  // total_test_case_count() - 1. If i is not in that range, returns NULL.
  const TestCase* UnitTest::GetTestCase(int i) const {
    return impl()->GetTestCase(i);
  }
  
  // Returns the TestResult containing information on test failures and
  // properties logged outside of individual test cases.
  const TestResult& UnitTest::ad_hoc_test_result() const {
    return *impl()->ad_hoc_test_result();
  }
  
  // Gets the i-th test case among all the test cases. i can range from 0 to
  // total_test_case_count() - 1. If i is not in that range, returns NULL.
  TestCase* UnitTest::GetMutableTestCase(int i) {
    return impl()->GetMutableTestCase(i);
  }
  
  // Returns the list of event listeners that can be used to track events
  // inside Google Test.
  TestEventListeners& UnitTest::listeners() {
    return *impl()->listeners();
  }
  
  // Registers and returns a global test environment.  When a test
  // program is run, all global test environments will be set-up in the
  // order they were registered.  After all tests in the program have
  // finished, all global test environments will be torn-down in the
  // *reverse* order they were registered.
  //
  // The UnitTest object takes ownership of the given environment.
  //
  // We don't protect this under mutex_, as we only support calling it
  // from the main thread.
  Environment* UnitTest::AddEnvironment(Environment* env) {
    if (env == NULL) {
      return NULL;
    }
  
    impl_->environments().push_back(env);
    return env;
  }
  
  // Adds a TestPartResult to the current TestResult object.  All Google Test
  // assertion macros (e.g. ASSERT_TRUE, EXPECT_EQ, etc) eventually call
  // this to report their results.  The user code should use the
  // assertion macros instead of calling this directly.
  void UnitTest::AddTestPartResult(
      TestPartResult::Type result_type,
      const char* file_name,
      int line_number,
      const std::string& message,
      const std::string& os_stack_trace) GTEST_LOCK_EXCLUDED_(mutex_) {
    Message msg;
    msg << message;
  
    internal::MutexLock lock(&mutex_);
    if (impl_->gtest_trace_stack().size() > 0) {
      msg << "\n" << GTEST_NAME_ << " trace:";
  
      for (int i = static_cast<int>(impl_->gtest_trace_stack().size());
           i > 0; --i) {
        const internal::TraceInfo& trace = impl_->gtest_trace_stack()[i - 1];
        msg << "\n" << internal::FormatFileLocation(trace.file, trace.line)
            << " " << trace.message;
      }
    }
  
    if (os_stack_trace.c_str() != NULL && !os_stack_trace.empty()) {
      msg << internal::kStackTraceMarker << os_stack_trace;
    }
  
    const TestPartResult result =
      TestPartResult(result_type, file_name, line_number,
                     msg.GetString().c_str());
    impl_->GetTestPartResultReporterForCurrentThread()->
        ReportTestPartResult(result);
  
    if (result_type != TestPartResult::kSuccess) {
      // gtest_break_on_failure takes precedence over
      // gtest_throw_on_failure.  This allows a user to set the latter
      // in the code (perhaps in order to use Google Test assertions
      // with another testing framework) and specify the former on the
      // command line for debugging.
      if (GTEST_FLAG(break_on_failure)) {
  #if GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_PHONE && !GTEST_OS_WINDOWS_RT
        // Using DebugBreak on Windows allows gtest to still break into a debugger
        // when a failure happens and both the --gtest_break_on_failure and
        // the --gtest_catch_exceptions flags are specified.
        DebugBreak();
  #else
        // Dereference NULL through a volatile pointer to prevent the compiler
        // from removing. We use this rather than abort() or __builtin_trap() for
        // portability: Symbian doesn't implement abort() well, and some debuggers
        // don't correctly trap abort().
        *static_cast<volatile int*>(NULL) = 1;
  #endif  // GTEST_OS_WINDOWS
      } else if (GTEST_FLAG(throw_on_failure)) {
  #if GTEST_HAS_EXCEPTIONS
        throw internal::GoogleTestFailureException(result);
  #else
        // We cannot call abort() as it generates a pop-up in debug mode
        // that cannot be suppressed in VC 7.1 or below.
        exit(1);
  #endif
      }
    }
  }
  
  // Adds a TestProperty to the current TestResult object when invoked from
  // inside a test, to current TestCase's ad_hoc_test_result_ when invoked
  // from SetUpTestCase or TearDownTestCase, or to the global property set
  // when invoked elsewhere.  If the result already contains a property with
  // the same key, the value will be updated.
  void UnitTest::RecordProperty(const std::string& key,
                                const std::string& value) {
    impl_->RecordProperty(TestProperty(key, value));
  }
  
  // Runs all tests in this UnitTest object and prints the result.
  // Returns 0 if successful, or 1 otherwise.
  //
  // We don't protect this under mutex_, as we only support calling it
  // from the main thread.
  int UnitTest::Run() {
    const bool in_death_test_child_process =
        internal::GTEST_FLAG(internal_run_death_test).length() > 0;
  
    // Google Test implements this protocol for catching that a test
    // program exits before returning control to Google Test:
    //
    //   1. Upon start, Google Test creates a file whose absolute path
    //      is specified by the environment variable
    //      TEST_PREMATURE_EXIT_FILE.
    //   2. When Google Test has finished its work, it deletes the file.
    //
    // This allows a test runner to set TEST_PREMATURE_EXIT_FILE before
    // running a Google-Test-based test program and check the existence
    // of the file at the end of the test execution to see if it has
    // exited prematurely.
  
    // If we are in the child process of a death test, don't
    // create/delete the premature exit file, as doing so is unnecessary
    // and will confuse the parent process.  Otherwise, create/delete
    // the file upon entering/leaving this function.  If the program
    // somehow exits before this function has a chance to return, the
    // premature-exit file will be left undeleted, causing a test runner
    // that understands the premature-exit-file protocol to report the
    // test as having failed.
    const internal::ScopedPrematureExitFile premature_exit_file(
        in_death_test_child_process ?
        NULL : internal::posix::GetEnv("TEST_PREMATURE_EXIT_FILE"));
  
    // Captures the value of GTEST_FLAG(catch_exceptions).  This value will be
    // used for the duration of the program.
    impl()->set_catch_exceptions(GTEST_FLAG(catch_exceptions));
  
  #if GTEST_HAS_SEH
    // Either the user wants Google Test to catch exceptions thrown by the
    // tests or this is executing in the context of death test child
    // process. In either case the user does not want to see pop-up dialogs
    // about crashes - they are expected.
    if (impl()->catch_exceptions() || in_death_test_child_process) {
  # if !GTEST_OS_WINDOWS_MOBILE && !GTEST_OS_WINDOWS_PHONE && !GTEST_OS_WINDOWS_RT
      // SetErrorMode doesn't exist on CE.
      SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOALIGNMENTFAULTEXCEPT |
                   SEM_NOGPFAULTERRORBOX | SEM_NOOPENFILEERRORBOX);
  # endif  // !GTEST_OS_WINDOWS_MOBILE
  
  # if (defined(_MSC_VER) || GTEST_OS_WINDOWS_MINGW) && !GTEST_OS_WINDOWS_MOBILE
      // Death test children can be terminated with _abort().  On Windows,
      // _abort() can show a dialog with a warning message.  This forces the
      // abort message to go to stderr instead.
      _set_error_mode(_OUT_TO_STDERR);
  # endif
  
  # if _MSC_VER >= 1400 && !GTEST_OS_WINDOWS_MOBILE
      // In the debug version, Visual Studio pops up a separate dialog
      // offering a choice to debug the aborted program. We need to suppress
      // this dialog or it will pop up for every EXPECT/ASSERT_DEATH statement
      // executed. Google Test will notify the user of any unexpected
      // failure via stderr.
      //
      // VC++ doesn't define _set_abort_behavior() prior to the version 8.0.
      // Users of prior VC versions shall suffer the agony and pain of
      // clicking through the countless debug dialogs.
      // TODO(vladl@google.com): find a way to suppress the abort dialog() in the
      // debug mode when compiled with VC 7.1 or lower.
      if (!GTEST_FLAG(break_on_failure))
        _set_abort_behavior(
            0x0,                                    // Clear the following flags:
            _WRITE_ABORT_MSG | _CALL_REPORTFAULT);  // pop-up window, core dump.
  # endif
    }
  #endif  // GTEST_HAS_SEH
  
    return internal::HandleExceptionsInMethodIfSupported(
        impl(),
        &internal::UnitTestImpl::RunAllTests,
        "auxiliary test code (environments or event listeners)") ? 0 : 1;
  }
  
  // Returns the working directory when the first TEST() or TEST_F() was
  // executed.
  const char* UnitTest::original_working_dir() const {
    return impl_->original_working_dir_.c_str();
  }
  
  // Returns the TestCase object for the test that's currently running,
  // or NULL if no test is running.
  const TestCase* UnitTest::current_test_case() const
      GTEST_LOCK_EXCLUDED_(mutex_) {
    internal::MutexLock lock(&mutex_);
    return impl_->current_test_case();
  }
  
  // Returns the TestInfo object for the test that's currently running,
  // or NULL if no test is running.
  const TestInfo* UnitTest::current_test_info() const
      GTEST_LOCK_EXCLUDED_(mutex_) {
    internal::MutexLock lock(&mutex_);
    return impl_->current_test_info();
  }
  
  // Returns the random seed used at the start of the current test run.
  int UnitTest::random_seed() const { return impl_->random_seed(); }
  
  #if GTEST_HAS_PARAM_TEST
  // Returns ParameterizedTestCaseRegistry object used to keep track of
  // value-parameterized tests and instantiate and register them.
  internal::ParameterizedTestCaseRegistry&
      UnitTest::parameterized_test_registry()
          GTEST_LOCK_EXCLUDED_(mutex_) {
    return impl_->parameterized_test_registry();
  }
  #endif  // GTEST_HAS_PARAM_TEST
  
  // Creates an empty UnitTest.
  UnitTest::UnitTest() {
    impl_ = new internal::UnitTestImpl(this);
  }
  
  // Destructor of UnitTest.
  UnitTest::~UnitTest() {
    delete impl_;
  }
  
  // Pushes a trace defined by SCOPED_TRACE() on to the per-thread
  // Google Test trace stack.
  void UnitTest::PushGTestTrace(const internal::TraceInfo& trace)
      GTEST_LOCK_EXCLUDED_(mutex_) {
    internal::MutexLock lock(&mutex_);
    impl_->gtest_trace_stack().push_back(trace);
  }
  
  // Pops a trace from the per-thread Google Test trace stack.
  void UnitTest::PopGTestTrace()
      GTEST_LOCK_EXCLUDED_(mutex_) {
    internal::MutexLock lock(&mutex_);
    impl_->gtest_trace_stack().pop_back();
  }
  
  namespace internal {
  
  UnitTestImpl::UnitTestImpl(UnitTest* parent)
      : parent_(parent),
        GTEST_DISABLE_MSC_WARNINGS_PUSH_(4355 /* using this in initializer */)
        default_global_test_part_result_reporter_(this),
        default_per_thread_test_part_result_reporter_(this),
        GTEST_DISABLE_MSC_WARNINGS_POP_()
        global_test_part_result_repoter_(
            &default_global_test_part_result_reporter_),
        per_thread_test_part_result_reporter_(
            &default_per_thread_test_part_result_reporter_),
  #if GTEST_HAS_PARAM_TEST
        parameterized_test_registry_(),
        parameterized_tests_registered_(false),
  #endif  // GTEST_HAS_PARAM_TEST
        last_death_test_case_(-1),
        current_test_case_(NULL),
        current_test_info_(NULL),
        ad_hoc_test_result_(),
        os_stack_trace_getter_(NULL),
        post_flag_parse_init_performed_(false),
        random_seed_(0),  // Will be overridden by the flag before first use.
        random_(0),  // Will be reseeded before first use.
        start_timestamp_(0),
        elapsed_time_(0),
  #if GTEST_HAS_DEATH_TEST
        death_test_factory_(new DefaultDeathTestFactory),
  #endif
        // Will be overridden by the flag before first use.
        catch_exceptions_(false) {
    listeners()->SetDefaultResultPrinter(new PrettyUnitTestResultPrinter);
  }
  
  UnitTestImpl::~UnitTestImpl() {
    // Deletes every TestCase.
    ForEach(test_cases_, internal::Delete<TestCase>);
  
    // Deletes every Environment.
    ForEach(environments_, internal::Delete<Environment>);
  
    delete os_stack_trace_getter_;
  }
  
  // Adds a TestProperty to the current TestResult object when invoked in a
  // context of a test, to current test case's ad_hoc_test_result when invoke
  // from SetUpTestCase/TearDownTestCase, or to the global property set
  // otherwise.  If the result already contains a property with the same key,
  // the value will be updated.
  void UnitTestImpl::RecordProperty(const TestProperty& test_property) {
    std::string xml_element;
    TestResult* test_result;  // TestResult appropriate for property recording.
  
    if (current_test_info_ != NULL) {
      xml_element = "testcase";
      test_result = &(current_test_info_->result_);
    } else if (current_test_case_ != NULL) {
      xml_element = "testsuite";
      test_result = &(current_test_case_->ad_hoc_test_result_);
    } else {
      xml_element = "testsuites";
      test_result = &ad_hoc_test_result_;
    }
    test_result->RecordProperty(xml_element, test_property);
  }
  
  #if GTEST_HAS_DEATH_TEST
  // Disables event forwarding if the control is currently in a death test
  // subprocess. Must not be called before InitGoogleTest.
  void UnitTestImpl::SuppressTestEventsIfInSubprocess() {
    if (internal_run_death_test_flag_.get() != NULL)
      listeners()->SuppressEventForwarding();
  }
  #endif  // GTEST_HAS_DEATH_TEST
  
  // Initializes event listeners performing XML output as specified by
  // UnitTestOptions. Must not be called before InitGoogleTest.
  void UnitTestImpl::ConfigureXmlOutput() {
    const std::string& output_format = UnitTestOptions::GetOutputFormat();
    if (output_format == "xml") {
      listeners()->SetDefaultXmlGenerator(new XmlUnitTestResultPrinter(
          UnitTestOptions::GetAbsolutePathToOutputFile().c_str()));
    } else if (output_format != "") {
      printf("WARNING: unrecognized output format \"%s\" ignored.\n",
             output_format.c_str());
      fflush(stdout);
    }
  }
  
  #if GTEST_CAN_STREAM_RESULTS_
  // Initializes event listeners for streaming test results in string form.
  // Must not be called before InitGoogleTest.
  void UnitTestImpl::ConfigureStreamingOutput() {
    const std::string& target = GTEST_FLAG(stream_result_to);
    if (!target.empty()) {
      const size_t pos = target.find(':');
      if (pos != std::string::npos) {
        listeners()->Append(new StreamingListener(target.substr(0, pos),
                                                  target.substr(pos+1)));
      } else {
        printf("WARNING: unrecognized streaming target \"%s\" ignored.\n",
               target.c_str());
        fflush(stdout);
      }
    }
  }
  #endif  // GTEST_CAN_STREAM_RESULTS_
  
  // Performs initialization dependent upon flag values obtained in
  // ParseGoogleTestFlagsOnly.  Is called from InitGoogleTest after the call to
  // ParseGoogleTestFlagsOnly.  In case a user neglects to call InitGoogleTest
  // this function is also called from RunAllTests.  Since this function can be
  // called more than once, it has to be idempotent.
  void UnitTestImpl::PostFlagParsingInit() {
    // Ensures that this function does not execute more than once.
    if (!post_flag_parse_init_performed_) {
      post_flag_parse_init_performed_ = true;
  
  #if defined(GTEST_CUSTOM_TEST_EVENT_LISTENER_)
      // Register to send notifications about key process state changes.
      listeners()->Append(new GTEST_CUSTOM_TEST_EVENT_LISTENER_());
  #endif  // defined(GTEST_CUSTOM_TEST_EVENT_LISTENER_)
  
  #if GTEST_HAS_DEATH_TEST
      InitDeathTestSubprocessControlInfo();
      SuppressTestEventsIfInSubprocess();
  #endif  // GTEST_HAS_DEATH_TEST
  
      // Registers parameterized tests. This makes parameterized tests
      // available to the UnitTest reflection API without running
      // RUN_ALL_TESTS.
      RegisterParameterizedTests();
  
      // Configures listeners for XML output. This makes it possible for users
      // to shut down the default XML output before invoking RUN_ALL_TESTS.
      ConfigureXmlOutput();
  
  #if GTEST_CAN_STREAM_RESULTS_
      // Configures listeners for streaming test results to the specified server.
      ConfigureStreamingOutput();
  #endif  // GTEST_CAN_STREAM_RESULTS_
    }
  }
  
  // A predicate that checks the name of a TestCase against a known
  // value.
  //
  // This is used for implementation of the UnitTest class only.  We put
  // it in the anonymous namespace to prevent polluting the outer
  // namespace.
  //
  // TestCaseNameIs is copyable.
  class TestCaseNameIs {
   public:
    // Constructor.
    explicit TestCaseNameIs(const std::string& name)
        : name_(name) {}
  
    // Returns true iff the name of test_case matches name_.
    bool operator()(const TestCase* test_case) const {
      return test_case != NULL && strcmp(test_case->name(), name_.c_str()) == 0;
    }
  
   private:
    std::string name_;
  };
  
  // Finds and returns a TestCase with the given name.  If one doesn't
  // exist, creates one and returns it.  It's the CALLER'S
  // RESPONSIBILITY to ensure that this function is only called WHEN THE
  // TESTS ARE NOT SHUFFLED.
  //
  // Arguments:
  //
  //   test_case_name: name of the test case
  //   type_param:     the name of the test case's type parameter, or NULL if
  //                   this is not a typed or a type-parameterized test case.
  //   set_up_tc:      pointer to the function that sets up the test case
  //   tear_down_tc:   pointer to the function that tears down the test case
  TestCase* UnitTestImpl::GetTestCase(const char* test_case_name,
                                      const char* type_param,
                                      Test::SetUpTestCaseFunc set_up_tc,
                                      Test::TearDownTestCaseFunc tear_down_tc) {
    // Can we find a TestCase with the given name?
    const std::vector<TestCase*>::const_iterator test_case =
        std::find_if(test_cases_.begin(), test_cases_.end(),
                     TestCaseNameIs(test_case_name));
  
    if (test_case != test_cases_.end())
      return *test_case;
  
    // No.  Let's create one.
    TestCase* const new_test_case =
        new TestCase(test_case_name, type_param, set_up_tc, tear_down_tc);
  
    // Is this a death test case?
    if (internal::UnitTestOptions::MatchesFilter(test_case_name,
                                                 kDeathTestCaseFilter)) {
      // Yes.  Inserts the test case after the last death test case
      // defined so far.  This only works when the test cases haven't
      // been shuffled.  Otherwise we may end up running a death test
      // after a non-death test.
      ++last_death_test_case_;
      test_cases_.insert(test_cases_.begin() + last_death_test_case_,
                         new_test_case);
    } else {
      // No.  Appends to the end of the list.
      test_cases_.push_back(new_test_case);
    }
  
    test_case_indices_.push_back(static_cast<int>(test_case_indices_.size()));
    return new_test_case;
  }
  
  // Helpers for setting up / tearing down the given environment.  They
  // are for use in the ForEach() function.
  static void SetUpEnvironment(Environment* env) { env->SetUp(); }
  static void TearDownEnvironment(Environment* env) { env->TearDown(); }
  
  // Runs all tests in this UnitTest object, prints the result, and
  // returns true if all tests are successful.  If any exception is
  // thrown during a test, the test is considered to be failed, but the
  // rest of the tests will still be run.
  //
  // When parameterized tests are enabled, it expands and registers
  // parameterized tests first in RegisterParameterizedTests().
  // All other functions called from RunAllTests() may safely assume that
  // parameterized tests are ready to be counted and run.
  bool UnitTestImpl::RunAllTests() {
    // Makes sure InitGoogleTest() was called.
    if (!GTestIsInitialized()) {
      printf("%s",
             "\nThis test program did NOT call ::testing::InitGoogleTest "
             "before calling RUN_ALL_TESTS().  Please fix it.\n");
      return false;
    }
  
    // Do not run any test if the --help flag was specified.
    if (g_help_flag)
      return true;
  
    // Repeats the call to the post-flag parsing initialization in case the
    // user didn't call InitGoogleTest.
    PostFlagParsingInit();
  
    // Even if sharding is not on, test runners may want to use the
    // GTEST_SHARD_STATUS_FILE to query whether the test supports the sharding
    // protocol.
    internal::WriteToShardStatusFileIfNeeded();
  
    // True iff we are in a subprocess for running a thread-safe-style
    // death test.
    bool in_subprocess_for_death_test = false;
  
  #if GTEST_HAS_DEATH_TEST
    in_subprocess_for_death_test = (internal_run_death_test_flag_.get() != NULL);
  # if defined(GTEST_EXTRA_DEATH_TEST_CHILD_SETUP_)
    if (in_subprocess_for_death_test) {
      GTEST_EXTRA_DEATH_TEST_CHILD_SETUP_();
    }
  # endif  // defined(GTEST_EXTRA_DEATH_TEST_CHILD_SETUP_)
  #endif  // GTEST_HAS_DEATH_TEST
  
    const bool should_shard = ShouldShard(kTestTotalShards, kTestShardIndex,
                                          in_subprocess_for_death_test);
  
    // Compares the full test names with the filter to decide which
    // tests to run.
    const bool has_tests_to_run = FilterTests(should_shard
                                                ? HONOR_SHARDING_PROTOCOL
                                                : IGNORE_SHARDING_PROTOCOL) > 0;
  
    // Lists the tests and exits if the --gtest_list_tests flag was specified.
    if (GTEST_FLAG(list_tests)) {
      // This must be called *after* FilterTests() has been called.
      ListTestsMatchingFilter();
      return true;
    }
  
    random_seed_ = GTEST_FLAG(shuffle) ?
        GetRandomSeedFromFlag(GTEST_FLAG(random_seed)) : 0;
  
    // True iff at least one test has failed.
    bool failed = false;
  
    TestEventListener* repeater = listeners()->repeater();
  
    start_timestamp_ = GetTimeInMillis();
    repeater->OnTestProgramStart(*parent_);
  
    // How many times to repeat the tests?  We don't want to repeat them
    // when we are inside the subprocess of a death test.
    const int repeat = in_subprocess_for_death_test ? 1 : GTEST_FLAG(repeat);
    // Repeats forever if the repeat count is negative.
    const bool forever = repeat < 0;
    for (int i = 0; forever || i != repeat; i++) {
      // We want to preserve failures generated by ad-hoc test
      // assertions executed before RUN_ALL_TESTS().
      ClearNonAdHocTestResult();
  
      const TimeInMillis start = GetTimeInMillis();
  
      // Shuffles test cases and tests if requested.
      if (has_tests_to_run && GTEST_FLAG(shuffle)) {
        random()->Reseed(random_seed_);
        // This should be done before calling OnTestIterationStart(),
        // such that a test event listener can see the actual test order
        // in the event.
        ShuffleTests();
      }
  
      // Tells the unit test event listeners that the tests are about to start.
      repeater->OnTestIterationStart(*parent_, i);
  
      // Runs each test case if there is at least one test to run.
      if (has_tests_to_run) {
        // Sets up all environments beforehand.
        repeater->OnEnvironmentsSetUpStart(*parent_);
        ForEach(environments_, SetUpEnvironment);
        repeater->OnEnvironmentsSetUpEnd(*parent_);
  
        // Runs the tests only if there was no fatal failure during global
        // set-up.
        if (!Test::HasFatalFailure()) {
          for (int test_index = 0; test_index < total_test_case_count();
               test_index++) {
            GetMutableTestCase(test_index)->Run();
          }
        }
  
        // Tears down all environments in reverse order afterwards.
        repeater->OnEnvironmentsTearDownStart(*parent_);
        std::for_each(environments_.rbegin(), environments_.rend(),
                      TearDownEnvironment);
        repeater->OnEnvironmentsTearDownEnd(*parent_);
      }
  
      elapsed_time_ = GetTimeInMillis() - start;
  
      // Tells the unit test event listener that the tests have just finished.
      repeater->OnTestIterationEnd(*parent_, i);
  
      // Gets the result and clears it.
      if (!Passed()) {
        failed = true;
      }
  
      // Restores the original test order after the iteration.  This
      // allows the user to quickly repro a failure that happens in the
      // N-th iteration without repeating the first (N - 1) iterations.
      // This is not enclosed in "if (GTEST_FLAG(shuffle)) { ... }", in
      // case the user somehow changes the value of the flag somewhere
      // (it's always safe to unshuffle the tests).
      UnshuffleTests();
  
      if (GTEST_FLAG(shuffle)) {
        // Picks a new random seed for each iteration.
        random_seed_ = GetNextRandomSeed(random_seed_);
      }
    }
  
    repeater->OnTestProgramEnd(*parent_);
  
    return !failed;
  }
  
  // Reads the GTEST_SHARD_STATUS_FILE environment variable, and creates the file
  // if the variable is present. If a file already exists at this location, this
  // function will write over it. If the variable is present, but the file cannot
  // be created, prints an error and exits.
  void WriteToShardStatusFileIfNeeded() {
    const char* const test_shard_file = posix::GetEnv(kTestShardStatusFile);
    if (test_shard_file != NULL) {
      FILE* const file = posix::FOpen(test_shard_file, "w");
      if (file == NULL) {
        ColoredPrintf(COLOR_RED,
                      "Could not write to the test shard status file \"%s\" "
                      "specified by the %s environment variable.\n",
                      test_shard_file, kTestShardStatusFile);
        fflush(stdout);
        exit(EXIT_FAILURE);
      }
      fclose(file);
    }
  }
  
  // Checks whether sharding is enabled by examining the relevant
  // environment variable values. If the variables are present,
  // but inconsistent (i.e., shard_index >= total_shards), prints
  // an error and exits. If in_subprocess_for_death_test, sharding is
  // disabled because it must only be applied to the original test
  // process. Otherwise, we could filter out death tests we intended to execute.
  bool ShouldShard(const char* total_shards_env,
                   const char* shard_index_env,
                   bool in_subprocess_for_death_test) {
    if (in_subprocess_for_death_test) {
      return false;
    }
  
    const Int32 total_shards = Int32FromEnvOrDie(total_shards_env, -1);
    const Int32 shard_index = Int32FromEnvOrDie(shard_index_env, -1);
  
    if (total_shards == -1 && shard_index == -1) {
      return false;
    } else if (total_shards == -1 && shard_index != -1) {
      const Message msg = Message()
        << "Invalid environment variables: you have "
        << kTestShardIndex << " = " << shard_index
        << ", but have left " << kTestTotalShards << " unset.\n";
      ColoredPrintf(COLOR_RED, msg.GetString().c_str());
      fflush(stdout);
      exit(EXIT_FAILURE);
    } else if (total_shards != -1 && shard_index == -1) {
      const Message msg = Message()
        << "Invalid environment variables: you have "
        << kTestTotalShards << " = " << total_shards
        << ", but have left " << kTestShardIndex << " unset.\n";
      ColoredPrintf(COLOR_RED, msg.GetString().c_str());
      fflush(stdout);
      exit(EXIT_FAILURE);
    } else if (shard_index < 0 || shard_index >= total_shards) {
      const Message msg = Message()
        << "Invalid environment variables: we require 0 <= "
        << kTestShardIndex << " < " << kTestTotalShards
        << ", but you have " << kTestShardIndex << "=" << shard_index
        << ", " << kTestTotalShards << "=" << total_shards << ".\n";
      ColoredPrintf(COLOR_RED, msg.GetString().c_str());
      fflush(stdout);
      exit(EXIT_FAILURE);
    }
  
    return total_shards > 1;
  }
  
  // Parses the environment variable var as an Int32. If it is unset,
  // returns default_val. If it is not an Int32, prints an error
  // and aborts.
  Int32 Int32FromEnvOrDie(const char* var, Int32 default_val) {
    const char* str_val = posix::GetEnv(var);
    if (str_val == NULL) {
      return default_val;
    }
  
    Int32 result;
    if (!ParseInt32(Message() << "The value of environment variable " << var,
                    str_val, &result)) {
      exit(EXIT_FAILURE);
    }
    return result;
  }
  
  // Given the total number of shards, the shard index, and the test id,
  // returns true iff the test should be run on this shard. The test id is
  // some arbitrary but unique non-negative integer assigned to each test
  // method. Assumes that 0 <= shard_index < total_shards.
  bool ShouldRunTestOnShard(int total_shards, int shard_index, int test_id) {
    return (test_id % total_shards) == shard_index;
  }
  
  // Compares the name of each test with the user-specified filter to
  // decide whether the test should be run, then records the result in
  // each TestCase and TestInfo object.
  // If shard_tests == true, further filters tests based on sharding
  // variables in the environment - see
  // http://code.google.com/p/googletest/wiki/GoogleTestAdvancedGuide.
  // Returns the number of tests that should run.
  int UnitTestImpl::FilterTests(ReactionToSharding shard_tests) {
    const Int32 total_shards = shard_tests == HONOR_SHARDING_PROTOCOL ?
        Int32FromEnvOrDie(kTestTotalShards, -1) : -1;
    const Int32 shard_index = shard_tests == HONOR_SHARDING_PROTOCOL ?
        Int32FromEnvOrDie(kTestShardIndex, -1) : -1;
  
    // num_runnable_tests are the number of tests that will
    // run across all shards (i.e., match filter and are not disabled).
    // num_selected_tests are the number of tests to be run on
    // this shard.
    int num_runnable_tests = 0;
    int num_selected_tests = 0;
    for (size_t i = 0; i < test_cases_.size(); i++) {
      TestCase* const test_case = test_cases_[i];
      const std::string &test_case_name = test_case->name();
      test_case->set_should_run(false);
  
      for (size_t j = 0; j < test_case->test_info_list().size(); j++) {
        TestInfo* const test_info = test_case->test_info_list()[j];
        const std::string test_name(test_info->name());
        // A test is disabled if test case name or test name matches
        // kDisableTestFilter.
        const bool is_disabled =
            internal::UnitTestOptions::MatchesFilter(test_case_name,
                                                     kDisableTestFilter) ||
            internal::UnitTestOptions::MatchesFilter(test_name,
                                                     kDisableTestFilter);
        test_info->is_disabled_ = is_disabled;
  
        const bool matches_filter =
            internal::UnitTestOptions::FilterMatchesTest(test_case_name,
                                                         test_name);
        test_info->matches_filter_ = matches_filter;
  
        const bool is_runnable =
            (GTEST_FLAG(also_run_disabled_tests) || !is_disabled) &&
            matches_filter;
  
        const bool is_selected = is_runnable &&
            (shard_tests == IGNORE_SHARDING_PROTOCOL ||
             ShouldRunTestOnShard(total_shards, shard_index,
                                  num_runnable_tests));
  
        num_runnable_tests += is_runnable;
        num_selected_tests += is_selected;
  
        test_info->should_run_ = is_selected;
        test_case->set_should_run(test_case->should_run() || is_selected);
      }
    }
    return num_selected_tests;
  }
  
  // Prints the given C-string on a single line by replacing all '\n'
  // characters with string "\\n".  If the output takes more than
  // max_length characters, only prints the first max_length characters
  // and "...".
  static void PrintOnOneLine(const char* str, int max_length) {
    if (str != NULL) {
      for (int i = 0; *str != '\0'; ++str) {
        if (i >= max_length) {
          printf("...");
          break;
        }
        if (*str == '\n') {
          printf("\\n");
          i += 2;
        } else {
          printf("%c", *str);
          ++i;
        }
      }
    }
  }
  
  // Prints the names of the tests matching the user-specified filter flag.
  void UnitTestImpl::ListTestsMatchingFilter() {
    // Print at most this many characters for each type/value parameter.
    const int kMaxParamLength = 250;
  
    for (size_t i = 0; i < test_cases_.size(); i++) {
      const TestCase* const test_case = test_cases_[i];
      bool printed_test_case_name = false;
  
      for (size_t j = 0; j < test_case->test_info_list().size(); j++) {
        const TestInfo* const test_info =
            test_case->test_info_list()[j];
        if (test_info->matches_filter_) {
          if (!printed_test_case_name) {
            printed_test_case_name = true;
            printf("%s.", test_case->name());
            if (test_case->type_param() != NULL) {
              printf("  # %s = ", kTypeParamLabel);
              // We print the type parameter on a single line to make
              // the output easy to parse by a program.
              PrintOnOneLine(test_case->type_param(), kMaxParamLength);
            }
            printf("\n");
          }
          printf("  %s", test_info->name());
          if (test_info->value_param() != NULL) {
            printf("  # %s = ", kValueParamLabel);
            // We print the value parameter on a single line to make the
            // output easy to parse by a program.
            PrintOnOneLine(test_info->value_param(), kMaxParamLength);
          }
          printf("\n");
        }
      }
    }
    fflush(stdout);
  }
  
  // Sets the OS stack trace getter.
  //
  // Does nothing if the input and the current OS stack trace getter are
  // the same; otherwise, deletes the old getter and makes the input the
  // current getter.
  void UnitTestImpl::set_os_stack_trace_getter(
      OsStackTraceGetterInterface* getter) {
    if (os_stack_trace_getter_ != getter) {
      delete os_stack_trace_getter_;
      os_stack_trace_getter_ = getter;
    }
  }
  
  // Returns the current OS stack trace getter if it is not NULL;
  // otherwise, creates an OsStackTraceGetter, makes it the current
  // getter, and returns it.
  OsStackTraceGetterInterface* UnitTestImpl::os_stack_trace_getter() {
    if (os_stack_trace_getter_ == NULL) {
  #ifdef GTEST_OS_STACK_TRACE_GETTER_
      os_stack_trace_getter_ = new GTEST_OS_STACK_TRACE_GETTER_;
  #else
      os_stack_trace_getter_ = new OsStackTraceGetter;
  #endif  // GTEST_OS_STACK_TRACE_GETTER_
    }
  
    return os_stack_trace_getter_;
  }
  
  // Returns the TestResult for the test that's currently running, or
  // the TestResult for the ad hoc test if no test is running.
  TestResult* UnitTestImpl::current_test_result() {
    return current_test_info_ ?
        &(current_test_info_->result_) : &ad_hoc_test_result_;
  }
  
  // Shuffles all test cases, and the tests within each test case,
  // making sure that death tests are still run first.
  void UnitTestImpl::ShuffleTests() {
    // Shuffles the death test cases.
    ShuffleRange(random(), 0, last_death_test_case_ + 1, &test_case_indices_);
  
    // Shuffles the non-death test cases.
    ShuffleRange(random(), last_death_test_case_ + 1,
                 static_cast<int>(test_cases_.size()), &test_case_indices_);
  
    // Shuffles the tests inside each test case.
    for (size_t i = 0; i < test_cases_.size(); i++) {
      test_cases_[i]->ShuffleTests(random());
    }
  }
  
  // Restores the test cases and tests to their order before the first shuffle.
  void UnitTestImpl::UnshuffleTests() {
    for (size_t i = 0; i < test_cases_.size(); i++) {
      // Unshuffles the tests in each test case.
      test_cases_[i]->UnshuffleTests();
      // Resets the index of each test case.
      test_case_indices_[i] = static_cast<int>(i);
    }
  }
  
  // Returns the current OS stack trace as an std::string.
  //
  // The maximum number of stack frames to be included is specified by
  // the gtest_stack_trace_depth flag.  The skip_count parameter
  // specifies the number of top frames to be skipped, which doesn't
  // count against the number of frames to be included.
  //
  // For example, if Foo() calls Bar(), which in turn calls
  // GetCurrentOsStackTraceExceptTop(..., 1), Foo() will be included in
  // the trace but Bar() and GetCurrentOsStackTraceExceptTop() won't.
  std::string GetCurrentOsStackTraceExceptTop(UnitTest* /*unit_test*/,
                                              int skip_count) {
    // We pass skip_count + 1 to skip this wrapper function in addition
    // to what the user really wants to skip.
    return GetUnitTestImpl()->CurrentOsStackTraceExceptTop(skip_count + 1);
  }
  
  // Used by the GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_ macro to
  // suppress unreachable code warnings.
  namespace {
  class ClassUniqueToAlwaysTrue {};
  }
  
  bool IsTrue(bool condition) { return condition; }
  
  bool AlwaysTrue() {
  #if GTEST_HAS_EXCEPTIONS
    // This condition is always false so AlwaysTrue() never actually throws,
    // but it makes the compiler think that it may throw.
    if (IsTrue(false))
      throw ClassUniqueToAlwaysTrue();
  #endif  // GTEST_HAS_EXCEPTIONS
    return true;
  }
  
  // If *pstr starts with the given prefix, modifies *pstr to be right
  // past the prefix and returns true; otherwise leaves *pstr unchanged
  // and returns false.  None of pstr, *pstr, and prefix can be NULL.
  bool SkipPrefix(const char* prefix, const char** pstr) {
    const size_t prefix_len = strlen(prefix);
    if (strncmp(*pstr, prefix, prefix_len) == 0) {
      *pstr += prefix_len;
      return true;
    }
    return false;
  }
  
  // Parses a string as a command line flag.  The string should have
  // the format "--flag=value".  When def_optional is true, the "=value"
  // part can be omitted.
  //
  // Returns the value of the flag, or NULL if the parsing failed.
  const char* ParseFlagValue(const char* str,
                             const char* flag,
                             bool def_optional) {
    // str and flag must not be NULL.
    if (str == NULL || flag == NULL) return NULL;
  
    // The flag must start with "--" followed by GTEST_FLAG_PREFIX_.
    const std::string flag_str = std::string("--") + GTEST_FLAG_PREFIX_ + flag;
    const size_t flag_len = flag_str.length();
    if (strncmp(str, flag_str.c_str(), flag_len) != 0) return NULL;
  
    // Skips the flag name.
    const char* flag_end = str + flag_len;
  
    // When def_optional is true, it's OK to not have a "=value" part.
    if (def_optional && (flag_end[0] == '\0')) {
      return flag_end;
    }
  
    // If def_optional is true and there are more characters after the
    // flag name, or if def_optional is false, there must be a '=' after
    // the flag name.
    if (flag_end[0] != '=') return NULL;
  
    // Returns the string after "=".
    return flag_end + 1;
  }
  
  // Parses a string for a bool flag, in the form of either
  // "--flag=value" or "--flag".
  //
  // In the former case, the value is taken as true as long as it does
  // not start with '0', 'f', or 'F'.
  //
  // In the latter case, the value is taken as true.
  //
  // On success, stores the value of the flag in *value, and returns
  // true.  On failure, returns false without changing *value.
  bool ParseBoolFlag(const char* str, const char* flag, bool* value) {
    // Gets the value of the flag as a string.
    const char* const value_str = ParseFlagValue(str, flag, true);
  
    // Aborts if the parsing failed.
    if (value_str == NULL) return false;
  
    // Converts the string value to a bool.
    *value = !(*value_str == '0' || *value_str == 'f' || *value_str == 'F');
    return true;
  }
  
  // Parses a string for an Int32 flag, in the form of
  // "--flag=value".
  //
  // On success, stores the value of the flag in *value, and returns
  // true.  On failure, returns false without changing *value.
  bool ParseInt32Flag(const char* str, const char* flag, Int32* value) {
    // Gets the value of the flag as a string.
    const char* const value_str = ParseFlagValue(str, flag, false);
  
    // Aborts if the parsing failed.
    if (value_str == NULL) return false;
  
    // Sets *value to the value of the flag.
    return ParseInt32(Message() << "The value of flag --" << flag,
                      value_str, value);
  }
  
  // Parses a string for a string flag, in the form of
  // "--flag=value".
  //
  // On success, stores the value of the flag in *value, and returns
  // true.  On failure, returns false without changing *value.
  bool ParseStringFlag(const char* str, const char* flag, std::string* value) {
    // Gets the value of the flag as a string.
    const char* const value_str = ParseFlagValue(str, flag, false);
  
    // Aborts if the parsing failed.
    if (value_str == NULL) return false;
  
    // Sets *value to the value of the flag.
    *value = value_str;
    return true;
  }
  
  // Determines whether a string has a prefix that Google Test uses for its
  // flags, i.e., starts with GTEST_FLAG_PREFIX_ or GTEST_FLAG_PREFIX_DASH_.
  // If Google Test detects that a command line flag has its prefix but is not
  // recognized, it will print its help message. Flags starting with
  // GTEST_INTERNAL_PREFIX_ followed by "internal_" are considered Google Test
  // internal flags and do not trigger the help message.
  static bool HasGoogleTestFlagPrefix(const char* str) {
    return (SkipPrefix("--", &str) ||
            SkipPrefix("-", &str) ||
            SkipPrefix("/", &str)) &&
           !SkipPrefix(GTEST_FLAG_PREFIX_ "internal_", &str) &&
           (SkipPrefix(GTEST_FLAG_PREFIX_, &str) ||
            SkipPrefix(GTEST_FLAG_PREFIX_DASH_, &str));
  }
  
  // Prints a string containing code-encoded text.  The following escape
  // sequences can be used in the string to control the text color:
  //
  //   @@    prints a single '@' character.
  //   @R    changes the color to red.
  //   @G    changes the color to green.
  //   @Y    changes the color to yellow.
  //   @D    changes to the default terminal text color.
  //
  // TODO(wan@google.com): Write tests for this once we add stdout
  // capturing to Google Test.
  static void PrintColorEncoded(const char* str) {
    GTestColor color = COLOR_DEFAULT;  // The current color.
  
    // Conceptually, we split the string into segments divided by escape
    // sequences.  Then we print one segment at a time.  At the end of
    // each iteration, the str pointer advances to the beginning of the
    // next segment.
    for (;;) {
      const char* p = strchr(str, '@');
      if (p == NULL) {
        ColoredPrintf(color, "%s", str);
        return;
      }
  
      ColoredPrintf(color, "%s", std::string(str, p).c_str());
  
      const char ch = p[1];
      str = p + 2;
      if (ch == '@') {
        ColoredPrintf(color, "@");
      } else if (ch == 'D') {
        color = COLOR_DEFAULT;
      } else if (ch == 'R') {
        color = COLOR_RED;
      } else if (ch == 'G') {
        color = COLOR_GREEN;
      } else if (ch == 'Y') {
        color = COLOR_YELLOW;
      } else {
        --str;
      }
    }
  }
  
  static const char kColorEncodedHelpMessage[] =
  "This program contains tests written using " GTEST_NAME_ ". You can use the\n"
  "following command line flags to control its behavior:\n"
  "\n"
  "Test Selection:\n"
  "  @G--" GTEST_FLAG_PREFIX_ "list_tests@D\n"
  "      List the names of all tests instead of running them. The name of\n"
  "      TEST(Foo, Bar) is \"Foo.Bar\".\n"
  "  @G--" GTEST_FLAG_PREFIX_ "filter=@YPOSTIVE_PATTERNS"
      "[@G-@YNEGATIVE_PATTERNS]@D\n"
  "      Run only the tests whose name matches one of the positive patterns but\n"
  "      none of the negative patterns. '?' matches any single character; '*'\n"
  "      matches any substring; ':' separates two patterns.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "also_run_disabled_tests@D\n"
  "      Run all disabled tests too.\n"
  "\n"
  "Test Execution:\n"
  "  @G--" GTEST_FLAG_PREFIX_ "repeat=@Y[COUNT]@D\n"
  "      Run the tests repeatedly; use a negative count to repeat forever.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "shuffle@D\n"
  "      Randomize tests' orders on every iteration.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "random_seed=@Y[NUMBER]@D\n"
  "      Random number seed to use for shuffling test orders (between 1 and\n"
  "      99999, or 0 to use a seed based on the current time).\n"
  "\n"
  "Test Output:\n"
  "  @G--" GTEST_FLAG_PREFIX_ "color=@Y(@Gyes@Y|@Gno@Y|@Gauto@Y)@D\n"
  "      Enable/disable colored output. The default is @Gauto@D.\n"
  "  -@G-" GTEST_FLAG_PREFIX_ "print_time=0@D\n"
  "      Don't print the elapsed time of each test.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "output=xml@Y[@G:@YDIRECTORY_PATH@G"
      GTEST_PATH_SEP_ "@Y|@G:@YFILE_PATH]@D\n"
  "      Generate an XML report in the given directory or with the given file\n"
  "      name. @YFILE_PATH@D defaults to @Gtest_details.xml@D.\n"
  #if GTEST_CAN_STREAM_RESULTS_
  "  @G--" GTEST_FLAG_PREFIX_ "stream_result_to=@YHOST@G:@YPORT@D\n"
  "      Stream test results to the given server.\n"
  #endif  // GTEST_CAN_STREAM_RESULTS_
  "\n"
  "Assertion Behavior:\n"
  #if GTEST_HAS_DEATH_TEST && !GTEST_OS_WINDOWS
  "  @G--" GTEST_FLAG_PREFIX_ "death_test_style=@Y(@Gfast@Y|@Gthreadsafe@Y)@D\n"
  "      Set the default death test style.\n"
  #endif  // GTEST_HAS_DEATH_TEST && !GTEST_OS_WINDOWS
  "  @G--" GTEST_FLAG_PREFIX_ "break_on_failure@D\n"
  "      Turn assertion failures into debugger break-points.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "throw_on_failure@D\n"
  "      Turn assertion failures into C++ exceptions.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "catch_exceptions=0@D\n"
  "      Do not report exceptions as test failures. Instead, allow them\n"
  "      to crash the program or throw a pop-up (on Windows).\n"
  "\n"
  "Except for @G--" GTEST_FLAG_PREFIX_ "list_tests@D, you can alternatively set "
      "the corresponding\n"
  "environment variable of a flag (all letters in upper-case). For example, to\n"
  "disable colored text output, you can either specify @G--" GTEST_FLAG_PREFIX_
      "color=no@D or set\n"
  "the @G" GTEST_FLAG_PREFIX_UPPER_ "COLOR@D environment variable to @Gno@D.\n"
  "\n"
  "For more information, please read the " GTEST_NAME_ " documentation at\n"
  "@G" GTEST_PROJECT_URL_ "@D. If you find a bug in " GTEST_NAME_ "\n"
  "(not one in your own code or tests), please report it to\n"
  "@G<" GTEST_DEV_EMAIL_ ">@D.\n";
  
  bool ParseGoogleTestFlag(const char* const arg) {
    return ParseBoolFlag(arg, kAlsoRunDisabledTestsFlag,
                         &GTEST_FLAG(also_run_disabled_tests)) ||
        ParseBoolFlag(arg, kBreakOnFailureFlag,
                      &GTEST_FLAG(break_on_failure)) ||
        ParseBoolFlag(arg, kCatchExceptionsFlag,
                      &GTEST_FLAG(catch_exceptions)) ||
        ParseStringFlag(arg, kColorFlag, &GTEST_FLAG(color)) ||
        ParseStringFlag(arg, kDeathTestStyleFlag,
                        &GTEST_FLAG(death_test_style)) ||
        ParseBoolFlag(arg, kDeathTestUseFork,
                      &GTEST_FLAG(death_test_use_fork)) ||
        ParseStringFlag(arg, kFilterFlag, &GTEST_FLAG(filter)) ||
        ParseStringFlag(arg, kInternalRunDeathTestFlag,
                        &GTEST_FLAG(internal_run_death_test)) ||
        ParseBoolFlag(arg, kListTestsFlag, &GTEST_FLAG(list_tests)) ||
        ParseStringFlag(arg, kOutputFlag, &GTEST_FLAG(output)) ||
        ParseBoolFlag(arg, kPrintTimeFlag, &GTEST_FLAG(print_time)) ||
        ParseInt32Flag(arg, kRandomSeedFlag, &GTEST_FLAG(random_seed)) ||
        ParseInt32Flag(arg, kRepeatFlag, &GTEST_FLAG(repeat)) ||
        ParseBoolFlag(arg, kShuffleFlag, &GTEST_FLAG(shuffle)) ||
        ParseInt32Flag(arg, kStackTraceDepthFlag,
                       &GTEST_FLAG(stack_trace_depth)) ||
        ParseStringFlag(arg, kStreamResultToFlag,
                        &GTEST_FLAG(stream_result_to)) ||
        ParseBoolFlag(arg, kThrowOnFailureFlag,
                      &GTEST_FLAG(throw_on_failure));
  }
  
  #if GTEST_USE_OWN_FLAGFILE_FLAG_
  void LoadFlagsFromFile(const std::string& path) {
    FILE* flagfile = posix::FOpen(path.c_str(), "r");
    if (!flagfile) {
      fprintf(stderr,
              "Unable to open file \"%s\"\n",
              GTEST_FLAG(flagfile).c_str());
      fflush(stderr);
      exit(EXIT_FAILURE);
    }
    std::string contents(ReadEntireFile(flagfile));
    posix::FClose(flagfile);
    std::vector<std::string> lines;
    SplitString(contents, '\n', &lines);
    for (size_t i = 0; i < lines.size(); ++i) {
      if (lines[i].empty())
        continue;
      if (!ParseGoogleTestFlag(lines[i].c_str()))
        g_help_flag = true;
    }
  }
  #endif  // GTEST_USE_OWN_FLAGFILE_FLAG_
  
  // Parses the command line for Google Test flags, without initializing
  // other parts of Google Test.  The type parameter CharType can be
  // instantiated to either char or wchar_t.
  template <typename CharType>
  void ParseGoogleTestFlagsOnlyImpl(int* argc, CharType** argv) {
    for (int i = 1; i < *argc; i++) {
      const std::string arg_string = StreamableToString(argv[i]);
      const char* const arg = arg_string.c_str();
  
      using internal::ParseBoolFlag;
      using internal::ParseInt32Flag;
      using internal::ParseStringFlag;
  
      bool remove_flag = false;
      if (ParseGoogleTestFlag(arg)) {
        remove_flag = true;
  #if GTEST_USE_OWN_FLAGFILE_FLAG_
      } else if (ParseStringFlag(arg, kFlagfileFlag, &GTEST_FLAG(flagfile))) {
        LoadFlagsFromFile(GTEST_FLAG(flagfile));
        remove_flag = true;
  #endif  // GTEST_USE_OWN_FLAGFILE_FLAG_
      } else if (arg_string == "--help" || arg_string == "-h" ||
                 arg_string == "-?" || arg_string == "/?" ||
                 HasGoogleTestFlagPrefix(arg)) {
        // Both help flag and unrecognized Google Test flags (excluding
        // internal ones) trigger help display.
        g_help_flag = true;
      }
  
      if (remove_flag) {
        // Shift the remainder of the argv list left by one.  Note
        // that argv has (*argc + 1) elements, the last one always being
        // NULL.  The following loop moves the trailing NULL element as
        // well.
        for (int j = i; j != *argc; j++) {
          argv[j] = argv[j + 1];
        }
  
        // Decrements the argument count.
        (*argc)--;
  
        // We also need to decrement the iterator as we just removed
        // an element.
        i--;
      }
    }
  
    if (g_help_flag) {
      // We print the help here instead of in RUN_ALL_TESTS(), as the
      // latter may not be called at all if the user is using Google
      // Test with another testing framework.
      PrintColorEncoded(kColorEncodedHelpMessage);
    }
  }
  
  // Parses the command line for Google Test flags, without initializing
  // other parts of Google Test.
  void ParseGoogleTestFlagsOnly(int* argc, char** argv) {
    ParseGoogleTestFlagsOnlyImpl(argc, argv);
  }
  void ParseGoogleTestFlagsOnly(int* argc, wchar_t** argv) {
    ParseGoogleTestFlagsOnlyImpl(argc, argv);
  }
  
  // The internal implementation of InitGoogleTest().
  //
  // The type parameter CharType can be instantiated to either char or
  // wchar_t.
  template <typename CharType>
  void InitGoogleTestImpl(int* argc, CharType** argv) {
    // We don't want to run the initialization code twice.
    if (GTestIsInitialized()) return;
  
    if (*argc <= 0) return;
  
    g_argvs.clear();
    for (int i = 0; i != *argc; i++) {
      g_argvs.push_back(StreamableToString(argv[i]));
    }
  
    ParseGoogleTestFlagsOnly(argc, argv);
    GetUnitTestImpl()->PostFlagParsingInit();
  }
  
  }  // namespace internal
  
  // Initializes Google Test.  This must be called before calling
  // RUN_ALL_TESTS().  In particular, it parses a command line for the
  // flags that Google Test recognizes.  Whenever a Google Test flag is
  // seen, it is removed from argv, and *argc is decremented.
  //
  // No value is returned.  Instead, the Google Test flag variables are
  // updated.
  //
  // Calling the function for the second time has no user-visible effect.
  void InitGoogleTest(int* argc, char** argv) {
  #if defined(GTEST_CUSTOM_INIT_GOOGLE_TEST_FUNCTION_)
    GTEST_CUSTOM_INIT_GOOGLE_TEST_FUNCTION_(argc, argv);
  #else  // defined(GTEST_CUSTOM_INIT_GOOGLE_TEST_FUNCTION_)
    internal::InitGoogleTestImpl(argc, argv);
  #endif  // defined(GTEST_CUSTOM_INIT_GOOGLE_TEST_FUNCTION_)
  }
  
  // This overloaded version can be used in Windows programs compiled in
  // UNICODE mode.
  void InitGoogleTest(int* argc, wchar_t** argv) {
  #if defined(GTEST_CUSTOM_INIT_GOOGLE_TEST_FUNCTION_)
    GTEST_CUSTOM_INIT_GOOGLE_TEST_FUNCTION_(argc, argv);
  #else  // defined(GTEST_CUSTOM_INIT_GOOGLE_TEST_FUNCTION_)
    internal::InitGoogleTestImpl(argc, argv);
  #endif  // defined(GTEST_CUSTOM_INIT_GOOGLE_TEST_FUNCTION_)
  }
  
  }  // namespace testing
  // Copyright 2005, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan), vladl@google.com (Vlad Losev)
  //
  // This file implements death tests.
  
  
  #if GTEST_HAS_DEATH_TEST
  
  # if GTEST_OS_MAC
  #  include <crt_externs.h>
  # endif  // GTEST_OS_MAC
  
  # include <errno.h>
  # include <fcntl.h>
  # include <limits.h>
  
  # if GTEST_OS_LINUX
  #  include <signal.h>
  # endif  // GTEST_OS_LINUX
  
  # include <stdarg.h>
  
  # if GTEST_OS_WINDOWS
  #  include <windows.h>
  # else
  #  include <sys/mman.h>
  #  include <sys/wait.h>
  # endif  // GTEST_OS_WINDOWS
  
  # if GTEST_OS_QNX
  #  include <spawn.h>
  # endif  // GTEST_OS_QNX
  
  #endif  // GTEST_HAS_DEATH_TEST
  
  
  // Indicates that this translation unit is part of Google Test's
  // implementation.  It must come before gtest-internal-inl.h is
  // included, or there will be a compiler error.  This trick exists to
  // prevent the accidental inclusion of gtest-internal-inl.h in the
  // user's code.
  #define GTEST_IMPLEMENTATION_ 1
  #undef GTEST_IMPLEMENTATION_
  
  namespace testing {
  
  // Constants.
  
  // The default death test style.
  static const char kDefaultDeathTestStyle[] = "fast";
  
  GTEST_DEFINE_string_(
      death_test_style,
      internal::StringFromGTestEnv("death_test_style", kDefaultDeathTestStyle),
      "Indicates how to run a death test in a forked child process: "
      "\"threadsafe\" (child process re-executes the test binary "
      "from the beginning, running only the specific death test) or "
      "\"fast\" (child process runs the death test immediately "
      "after forking).");
  
  GTEST_DEFINE_bool_(
      death_test_use_fork,
      internal::BoolFromGTestEnv("death_test_use_fork", false),
      "Instructs to use fork()/_exit() instead of clone() in death tests. "
      "Ignored and always uses fork() on POSIX systems where clone() is not "
      "implemented. Useful when running under valgrind or similar tools if "
      "those do not support clone(). Valgrind 3.3.1 will just fail if "
      "it sees an unsupported combination of clone() flags. "
      "It is not recommended to use this flag w/o valgrind though it will "
      "work in 99% of the cases. Once valgrind is fixed, this flag will "
      "most likely be removed.");
  
  namespace internal {
  GTEST_DEFINE_string_(
      internal_run_death_test, "",
      "Indicates the file, line number, temporal index of "
      "the single death test to run, and a file descriptor to "
      "which a success code may be sent, all separated by "
      "the '|' characters.  This flag is specified if and only if the current "
      "process is a sub-process launched for running a thread-safe "
      "death test.  FOR INTERNAL USE ONLY.");
  }  // namespace internal
  
  #if GTEST_HAS_DEATH_TEST
  
  namespace internal {
  
  // Valid only for fast death tests. Indicates the code is running in the
  // child process of a fast style death test.
  # if !GTEST_OS_WINDOWS
  static bool g_in_fast_death_test_child = false;
  # endif
  
  // Returns a Boolean value indicating whether the caller is currently
  // executing in the context of the death test child process.  Tools such as
  // Valgrind heap checkers may need this to modify their behavior in death
  // tests.  IMPORTANT: This is an internal utility.  Using it may break the
  // implementation of death tests.  User code MUST NOT use it.
  bool InDeathTestChild() {
  # if GTEST_OS_WINDOWS
  
    // On Windows, death tests are thread-safe regardless of the value of the
    // death_test_style flag.
    return !GTEST_FLAG(internal_run_death_test).empty();
  
  # else
  
    if (GTEST_FLAG(death_test_style) == "threadsafe")
      return !GTEST_FLAG(internal_run_death_test).empty();
    else
      return g_in_fast_death_test_child;
  #endif
  }
  
  }  // namespace internal
  
  // ExitedWithCode constructor.
  ExitedWithCode::ExitedWithCode(int exit_code) : exit_code_(exit_code) {
  }
  
  // ExitedWithCode function-call operator.
  bool ExitedWithCode::operator()(int exit_status) const {
  # if GTEST_OS_WINDOWS
  
    return exit_status == exit_code_;
  
  # else
  
    return WIFEXITED(exit_status) && WEXITSTATUS(exit_status) == exit_code_;
  
  # endif  // GTEST_OS_WINDOWS
  }
  
  # if !GTEST_OS_WINDOWS
  // KilledBySignal constructor.
  KilledBySignal::KilledBySignal(int signum) : signum_(signum) {
  }
  
  // KilledBySignal function-call operator.
  bool KilledBySignal::operator()(int exit_status) const {
  #  if defined(GTEST_KILLED_BY_SIGNAL_OVERRIDE_)
    {
      bool result;
      if (GTEST_KILLED_BY_SIGNAL_OVERRIDE_(signum_, exit_status, &result)) {
        return result;
      }
    }
  #  endif  // defined(GTEST_KILLED_BY_SIGNAL_OVERRIDE_)
    return WIFSIGNALED(exit_status) && WTERMSIG(exit_status) == signum_;
  }
  # endif  // !GTEST_OS_WINDOWS
  
  namespace internal {
  
  // Utilities needed for death tests.
  
  // Generates a textual description of a given exit code, in the format
  // specified by wait(2).
  static std::string ExitSummary(int exit_code) {
    Message m;
  
  # if GTEST_OS_WINDOWS
  
    m << "Exited with exit status " << exit_code;
  
  # else
  
    if (WIFEXITED(exit_code)) {
      m << "Exited with exit status " << WEXITSTATUS(exit_code);
    } else if (WIFSIGNALED(exit_code)) {
      m << "Terminated by signal " << WTERMSIG(exit_code);
    }
  #  ifdef WCOREDUMP
    if (WCOREDUMP(exit_code)) {
      m << " (core dumped)";
    }
  #  endif
  # endif  // GTEST_OS_WINDOWS
  
    return m.GetString();
  }
  
  // Returns true if exit_status describes a process that was terminated
  // by a signal, or exited normally with a nonzero exit code.
  bool ExitedUnsuccessfully(int exit_status) {
    return !ExitedWithCode(0)(exit_status);
  }
  
  # if !GTEST_OS_WINDOWS
  // Generates a textual failure message when a death test finds more than
  // one thread running, or cannot determine the number of threads, prior
  // to executing the given statement.  It is the responsibility of the
  // caller not to pass a thread_count of 1.
  static std::string DeathTestThreadWarning(size_t thread_count) {
    Message msg;
    msg << "Death tests use fork(), which is unsafe particularly"
        << " in a threaded context. For this test, " << GTEST_NAME_ << " ";
    if (thread_count == 0)
      msg << "couldn't detect the number of threads.";
    else
      msg << "detected " << thread_count << " threads.";
    return msg.GetString();
  }
  # endif  // !GTEST_OS_WINDOWS
  
  // Flag characters for reporting a death test that did not die.
  static const char kDeathTestLived = 'L';
  static const char kDeathTestReturned = 'R';
  static const char kDeathTestThrew = 'T';
  static const char kDeathTestInternalError = 'I';
  
  // An enumeration describing all of the possible ways that a death test can
  // conclude.  DIED means that the process died while executing the test
  // code; LIVED means that process lived beyond the end of the test code;
  // RETURNED means that the test statement attempted to execute a return
  // statement, which is not allowed; THREW means that the test statement
  // returned control by throwing an exception.  IN_PROGRESS means the test
  // has not yet concluded.
  // TODO(vladl@google.com): Unify names and possibly values for
  // AbortReason, DeathTestOutcome, and flag characters above.
  enum DeathTestOutcome { IN_PROGRESS, DIED, LIVED, RETURNED, THREW };
  
  // Routine for aborting the program which is safe to call from an
  // exec-style death test child process, in which case the error
  // message is propagated back to the parent process.  Otherwise, the
  // message is simply printed to stderr.  In either case, the program
  // then exits with status 1.
  void DeathTestAbort(const std::string& message) {
    // On a POSIX system, this function may be called from a threadsafe-style
    // death test child process, which operates on a very small stack.  Use
    // the heap for any additional non-minuscule memory requirements.
    const InternalRunDeathTestFlag* const flag =
        GetUnitTestImpl()->internal_run_death_test_flag();
    if (flag != NULL) {
      FILE* parent = posix::FDOpen(flag->write_fd(), "w");
      fputc(kDeathTestInternalError, parent);
      fprintf(parent, "%s", message.c_str());
      fflush(parent);
      _exit(1);
    } else {
      fprintf(stderr, "%s", message.c_str());
      fflush(stderr);
      posix::Abort();
    }
  }
  
  // A replacement for CHECK that calls DeathTestAbort if the assertion
  // fails.
  # define GTEST_DEATH_TEST_CHECK_(expression) \
    do { \
      if (!::testing::internal::IsTrue(expression)) { \
        DeathTestAbort( \
            ::std::string("CHECK failed: File ") + __FILE__ +  ", line " \
            + ::testing::internal::StreamableToString(__LINE__) + ": " \
            + #expression); \
      } \
    } while (::testing::internal::AlwaysFalse())
  
  // This macro is similar to GTEST_DEATH_TEST_CHECK_, but it is meant for
  // evaluating any system call that fulfills two conditions: it must return
  // -1 on failure, and set errno to EINTR when it is interrupted and
  // should be tried again.  The macro expands to a loop that repeatedly
  // evaluates the expression as long as it evaluates to -1 and sets
  // errno to EINTR.  If the expression evaluates to -1 but errno is
  // something other than EINTR, DeathTestAbort is called.
  # define GTEST_DEATH_TEST_CHECK_SYSCALL_(expression) \
    do { \
      int gtest_retval; \
      do { \
        gtest_retval = (expression); \
      } while (gtest_retval == -1 && errno == EINTR); \
      if (gtest_retval == -1) { \
        DeathTestAbort( \
            ::std::string("CHECK failed: File ") + __FILE__ + ", line " \
            + ::testing::internal::StreamableToString(__LINE__) + ": " \
            + #expression + " != -1"); \
      } \
    } while (::testing::internal::AlwaysFalse())
  
  // Returns the message describing the last system error in errno.
  std::string GetLastErrnoDescription() {
      return errno == 0 ? "" : posix::StrError(errno);
  }
  
  // This is called from a death test parent process to read a failure
  // message from the death test child process and log it with the FATAL
  // severity. On Windows, the message is read from a pipe handle. On other
  // platforms, it is read from a file descriptor.
  static void FailFromInternalError(int fd) {
    Message error;
    char buffer[256];
    int num_read;
  
    do {
      while ((num_read = posix::Read(fd, buffer, 255)) > 0) {
        buffer[num_read] = '\0';
        error << buffer;
      }
    } while (num_read == -1 && errno == EINTR);
  
    if (num_read == 0) {
      GTEST_LOG_(FATAL) << error.GetString();
    } else {
      const int last_error = errno;
      GTEST_LOG_(FATAL) << "Error while reading death test internal: "
                        << GetLastErrnoDescription() << " [" << last_error << "]";
    }
  }
  
  // Death test constructor.  Increments the running death test count
  // for the current test.
  DeathTest::DeathTest() {
    TestInfo* const info = GetUnitTestImpl()->current_test_info();
    if (info == NULL) {
      DeathTestAbort("Cannot run a death test outside of a TEST or "
                     "TEST_F construct");
    }
  }
  
  // Creates and returns a death test by dispatching to the current
  // death test factory.
  bool DeathTest::Create(const char* statement, const RE* regex,
                         const char* file, int line, DeathTest** test) {
    return GetUnitTestImpl()->death_test_factory()->Create(
        statement, regex, file, line, test);
  }
  
  const char* DeathTest::LastMessage() {
    return last_death_test_message_.c_str();
  }
  
  void DeathTest::set_last_death_test_message(const std::string& message) {
    last_death_test_message_ = message;
  }
  
  std::string DeathTest::last_death_test_message_;
  
  // Provides cross platform implementation for some death functionality.
  class DeathTestImpl : public DeathTest {
   protected:
    DeathTestImpl(const char* a_statement, const RE* a_regex)
        : statement_(a_statement),
          regex_(a_regex),
          spawned_(false),
          status_(-1),
          outcome_(IN_PROGRESS),
          read_fd_(-1),
          write_fd_(-1) {}
  
    // read_fd_ is expected to be closed and cleared by a derived class.
    ~DeathTestImpl() { GTEST_DEATH_TEST_CHECK_(read_fd_ == -1); }
  
    void Abort(AbortReason reason);
    virtual bool Passed(bool status_ok);
  
    const char* statement() const { return statement_; }
    const RE* regex() const { return regex_; }
    bool spawned() const { return spawned_; }
    void set_spawned(bool is_spawned) { spawned_ = is_spawned; }
    int status() const { return status_; }
    void set_status(int a_status) { status_ = a_status; }
    DeathTestOutcome outcome() const { return outcome_; }
    void set_outcome(DeathTestOutcome an_outcome) { outcome_ = an_outcome; }
    int read_fd() const { return read_fd_; }
    void set_read_fd(int fd) { read_fd_ = fd; }
    int write_fd() const { return write_fd_; }
    void set_write_fd(int fd) { write_fd_ = fd; }
  
    // Called in the parent process only. Reads the result code of the death
    // test child process via a pipe, interprets it to set the outcome_
    // member, and closes read_fd_.  Outputs diagnostics and terminates in
    // case of unexpected codes.
    void ReadAndInterpretStatusByte();
  
   private:
    // The textual content of the code this object is testing.  This class
    // doesn't own this string and should not attempt to delete it.
    const char* const statement_;
    // The regular expression which test output must match.  DeathTestImpl
    // doesn't own this object and should not attempt to delete it.
    const RE* const regex_;
    // True if the death test child process has been successfully spawned.
    bool spawned_;
    // The exit status of the child process.
    int status_;
    // How the death test concluded.
    DeathTestOutcome outcome_;
    // Descriptor to the read end of the pipe to the child process.  It is
    // always -1 in the child process.  The child keeps its write end of the
    // pipe in write_fd_.
    int read_fd_;
    // Descriptor to the child's write end of the pipe to the parent process.
    // It is always -1 in the parent process.  The parent keeps its end of the
    // pipe in read_fd_.
    int write_fd_;
  };
  
  // Called in the parent process only. Reads the result code of the death
  // test child process via a pipe, interprets it to set the outcome_
  // member, and closes read_fd_.  Outputs diagnostics and terminates in
  // case of unexpected codes.
  void DeathTestImpl::ReadAndInterpretStatusByte() {
    char flag;
    int bytes_read;
  
    // The read() here blocks until data is available (signifying the
    // failure of the death test) or until the pipe is closed (signifying
    // its success), so it's okay to call this in the parent before
    // the child process has exited.
    do {
      bytes_read = posix::Read(read_fd(), &flag, 1);
    } while (bytes_read == -1 && errno == EINTR);
  
    if (bytes_read == 0) {
      set_outcome(DIED);
    } else if (bytes_read == 1) {
      switch (flag) {
        case kDeathTestReturned:
          set_outcome(RETURNED);
          break;
        case kDeathTestThrew:
          set_outcome(THREW);
          break;
        case kDeathTestLived:
          set_outcome(LIVED);
          break;
        case kDeathTestInternalError:
          FailFromInternalError(read_fd());  // Does not return.
          break;
        default:
          GTEST_LOG_(FATAL) << "Death test child process reported "
                            << "unexpected status byte ("
                            << static_cast<unsigned int>(flag) << ")";
      }
    } else {
      GTEST_LOG_(FATAL) << "Read from death test child process failed: "
                        << GetLastErrnoDescription();
    }
    GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(read_fd()));
    set_read_fd(-1);
  }
  
  // Signals that the death test code which should have exited, didn't.
  // Should be called only in a death test child process.
  // Writes a status byte to the child's status file descriptor, then
  // calls _exit(1).
  void DeathTestImpl::Abort(AbortReason reason) {
    // The parent process considers the death test to be a failure if
    // it finds any data in our pipe.  So, here we write a single flag byte
    // to the pipe, then exit.
    const char status_ch =
        reason == TEST_DID_NOT_DIE ? kDeathTestLived :
        reason == TEST_THREW_EXCEPTION ? kDeathTestThrew : kDeathTestReturned;
  
    GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Write(write_fd(), &status_ch, 1));
    // We are leaking the descriptor here because on some platforms (i.e.,
    // when built as Windows DLL), destructors of global objects will still
    // run after calling _exit(). On such systems, write_fd_ will be
    // indirectly closed from the destructor of UnitTestImpl, causing double
    // close if it is also closed here. On debug configurations, double close
    // may assert. As there are no in-process buffers to flush here, we are
    // relying on the OS to close the descriptor after the process terminates
    // when the destructors are not run.
    _exit(1);  // Exits w/o any normal exit hooks (we were supposed to crash)
  }
  
  // Returns an indented copy of stderr output for a death test.
  // This makes distinguishing death test output lines from regular log lines
  // much easier.
  static ::std::string FormatDeathTestOutput(const ::std::string& output) {
    ::std::string ret;
    for (size_t at = 0; ; ) {
      const size_t line_end = output.find('\n', at);
      ret += "[  DEATH   ] ";
      if (line_end == ::std::string::npos) {
        ret += output.substr(at);
        break;
      }
      ret += output.substr(at, line_end + 1 - at);
      at = line_end + 1;
    }
    return ret;
  }
  
  // Assesses the success or failure of a death test, using both private
  // members which have previously been set, and one argument:
  //
  // Private data members:
  //   outcome:  An enumeration describing how the death test
  //             concluded: DIED, LIVED, THREW, or RETURNED.  The death test
  //             fails in the latter three cases.
  //   status:   The exit status of the child process. On *nix, it is in the
  //             in the format specified by wait(2). On Windows, this is the
  //             value supplied to the ExitProcess() API or a numeric code
  //             of the exception that terminated the program.
  //   regex:    A regular expression object to be applied to
  //             the test's captured standard error output; the death test
  //             fails if it does not match.
  //
  // Argument:
  //   status_ok: true if exit_status is acceptable in the context of
  //              this particular death test, which fails if it is false
  //
  // Returns true iff all of the above conditions are met.  Otherwise, the
  // first failing condition, in the order given above, is the one that is
  // reported. Also sets the last death test message string.
  bool DeathTestImpl::Passed(bool status_ok) {
    if (!spawned())
      return false;
  
    const std::string error_message = GetCapturedStderr();
  
    bool success = false;
    Message buffer;
  
    buffer << "Death test: " << statement() << "\n";
    switch (outcome()) {
      case LIVED:
        buffer << "    Result: failed to die.\n"
               << " Error msg:\n" << FormatDeathTestOutput(error_message);
        break;
      case THREW:
        buffer << "    Result: threw an exception.\n"
               << " Error msg:\n" << FormatDeathTestOutput(error_message);
        break;
      case RETURNED:
        buffer << "    Result: illegal return in test statement.\n"
               << " Error msg:\n" << FormatDeathTestOutput(error_message);
        break;
      case DIED:
        if (status_ok) {
          const bool matched = RE::PartialMatch(error_message.c_str(), *regex());
          if (matched) {
            success = true;
          } else {
            buffer << "    Result: died but not with expected error.\n"
                   << "  Expected: " << regex()->pattern() << "\n"
                   << "Actual msg:\n" << FormatDeathTestOutput(error_message);
          }
        } else {
          buffer << "    Result: died but not with expected exit code:\n"
                 << "            " << ExitSummary(status()) << "\n"
                 << "Actual msg:\n" << FormatDeathTestOutput(error_message);
        }
        break;
      case IN_PROGRESS:
      default:
        GTEST_LOG_(FATAL)
            << "DeathTest::Passed somehow called before conclusion of test";
    }
  
    DeathTest::set_last_death_test_message(buffer.GetString());
    return success;
  }
  
  # if GTEST_OS_WINDOWS
  // WindowsDeathTest implements death tests on Windows. Due to the
  // specifics of starting new processes on Windows, death tests there are
  // always threadsafe, and Google Test considers the
  // --gtest_death_test_style=fast setting to be equivalent to
  // --gtest_death_test_style=threadsafe there.
  //
  // A few implementation notes:  Like the Linux version, the Windows
  // implementation uses pipes for child-to-parent communication. But due to
  // the specifics of pipes on Windows, some extra steps are required:
  //
  // 1. The parent creates a communication pipe and stores handles to both
  //    ends of it.
  // 2. The parent starts the child and provides it with the information
  //    necessary to acquire the handle to the write end of the pipe.
  // 3. The child acquires the write end of the pipe and signals the parent
  //    using a Windows event.
  // 4. Now the parent can release the write end of the pipe on its side. If
  //    this is done before step 3, the object's reference count goes down to
  //    0 and it is destroyed, preventing the child from acquiring it. The
  //    parent now has to release it, or read operations on the read end of
  //    the pipe will not return when the child terminates.
  // 5. The parent reads child's output through the pipe (outcome code and
  //    any possible error messages) from the pipe, and its stderr and then
  //    determines whether to fail the test.
  //
  // Note: to distinguish Win32 API calls from the local method and function
  // calls, the former are explicitly resolved in the global namespace.
  //
  class WindowsDeathTest : public DeathTestImpl {
   public:
    WindowsDeathTest(const char* a_statement,
                     const RE* a_regex,
                     const char* file,
                     int line)
        : DeathTestImpl(a_statement, a_regex), file_(file), line_(line) {}
  
    // All of these virtual functions are inherited from DeathTest.
    virtual int Wait();
    virtual TestRole AssumeRole();
  
   private:
    // The name of the file in which the death test is located.
    const char* const file_;
    // The line number on which the death test is located.
    const int line_;
    // Handle to the write end of the pipe to the child process.
    AutoHandle write_handle_;
    // Child process handle.
    AutoHandle child_handle_;
    // Event the child process uses to signal the parent that it has
    // acquired the handle to the write end of the pipe. After seeing this
    // event the parent can release its own handles to make sure its
    // ReadFile() calls return when the child terminates.
    AutoHandle event_handle_;
  };
  
  // Waits for the child in a death test to exit, returning its exit
  // status, or 0 if no child process exists.  As a side effect, sets the
  // outcome data member.
  int WindowsDeathTest::Wait() {
    if (!spawned())
      return 0;
  
    // Wait until the child either signals that it has acquired the write end
    // of the pipe or it dies.
    const HANDLE wait_handles[2] = { child_handle_.Get(), event_handle_.Get() };
    switch (::WaitForMultipleObjects(2,
                                     wait_handles,
                                     FALSE,  // Waits for any of the handles.
                                     INFINITE)) {
      case WAIT_OBJECT_0:
      case WAIT_OBJECT_0 + 1:
        break;
      default:
        GTEST_DEATH_TEST_CHECK_(false);  // Should not get here.
    }
  
    // The child has acquired the write end of the pipe or exited.
    // We release the handle on our side and continue.
    write_handle_.Reset();
    event_handle_.Reset();
  
    ReadAndInterpretStatusByte();
  
    // Waits for the child process to exit if it haven't already. This
    // returns immediately if the child has already exited, regardless of
    // whether previous calls to WaitForMultipleObjects synchronized on this
    // handle or not.
    GTEST_DEATH_TEST_CHECK_(
        WAIT_OBJECT_0 == ::WaitForSingleObject(child_handle_.Get(),
                                               INFINITE));
    DWORD status_code;
    GTEST_DEATH_TEST_CHECK_(
        ::GetExitCodeProcess(child_handle_.Get(), &status_code) != FALSE);
    child_handle_.Reset();
    set_status(static_cast<int>(status_code));
    return status();
  }
  
  // The AssumeRole process for a Windows death test.  It creates a child
  // process with the same executable as the current process to run the
  // death test.  The child process is given the --gtest_filter and
  // --gtest_internal_run_death_test flags such that it knows to run the
  // current death test only.
  DeathTest::TestRole WindowsDeathTest::AssumeRole() {
    const UnitTestImpl* const impl = GetUnitTestImpl();
    const InternalRunDeathTestFlag* const flag =
        impl->internal_run_death_test_flag();
    const TestInfo* const info = impl->current_test_info();
    const int death_test_index = info->result()->death_test_count();
  
    if (flag != NULL) {
      // ParseInternalRunDeathTestFlag() has performed all the necessary
      // processing.
      set_write_fd(flag->write_fd());
      return EXECUTE_TEST;
    }
  
    // WindowsDeathTest uses an anonymous pipe to communicate results of
    // a death test.
    SECURITY_ATTRIBUTES handles_are_inheritable = {
      sizeof(SECURITY_ATTRIBUTES), NULL, TRUE };
    HANDLE read_handle, write_handle;
    GTEST_DEATH_TEST_CHECK_(
        ::CreatePipe(&read_handle, &write_handle, &handles_are_inheritable,
                     0)  // Default buffer size.
        != FALSE);
    set_read_fd(::_open_osfhandle(reinterpret_cast<intptr_t>(read_handle),
                                  O_RDONLY));
    write_handle_.Reset(write_handle);
    event_handle_.Reset(::CreateEvent(
        &handles_are_inheritable,
        TRUE,    // The event will automatically reset to non-signaled state.
        FALSE,   // The initial state is non-signalled.
        NULL));  // The even is unnamed.
    GTEST_DEATH_TEST_CHECK_(event_handle_.Get() != NULL);
    const std::string filter_flag =
        std::string("--") + GTEST_FLAG_PREFIX_ + kFilterFlag + "=" +
        info->test_case_name() + "." + info->name();
    const std::string internal_flag =
        std::string("--") + GTEST_FLAG_PREFIX_ + kInternalRunDeathTestFlag +
        "=" + file_ + "|" + StreamableToString(line_) + "|" +
        StreamableToString(death_test_index) + "|" +
        StreamableToString(static_cast<unsigned int>(::GetCurrentProcessId())) +
        // size_t has the same width as pointers on both 32-bit and 64-bit
        // Windows platforms.
        // See http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx.
        "|" + StreamableToString(reinterpret_cast<size_t>(write_handle)) +
        "|" + StreamableToString(reinterpret_cast<size_t>(event_handle_.Get()));
  
    char executable_path[_MAX_PATH + 1];  // NOLINT
    GTEST_DEATH_TEST_CHECK_(
        _MAX_PATH + 1 != ::GetModuleFileNameA(NULL,
                                              executable_path,
                                              _MAX_PATH));
  
    std::string command_line =
        std::string(::GetCommandLineA()) + " " + filter_flag + " \"" +
        internal_flag + "\"";
  
    DeathTest::set_last_death_test_message("");
  
    CaptureStderr();
    // Flush the log buffers since the log streams are shared with the child.
    FlushInfoLog();
  
    // The child process will share the standard handles with the parent.
    STARTUPINFOA startup_info;
    memset(&startup_info, 0, sizeof(STARTUPINFO));
    startup_info.dwFlags = STARTF_USESTDHANDLES;
    startup_info.hStdInput = ::GetStdHandle(STD_INPUT_HANDLE);
    startup_info.hStdOutput = ::GetStdHandle(STD_OUTPUT_HANDLE);
    startup_info.hStdError = ::GetStdHandle(STD_ERROR_HANDLE);
  
    PROCESS_INFORMATION process_info;
    GTEST_DEATH_TEST_CHECK_(::CreateProcessA(
        executable_path,
        const_cast<char*>(command_line.c_str()),
        NULL,   // Retuned process handle is not inheritable.
        NULL,   // Retuned thread handle is not inheritable.
        TRUE,   // Child inherits all inheritable handles (for write_handle_).
        0x0,    // Default creation flags.
        NULL,   // Inherit the parent's environment.
        UnitTest::GetInstance()->original_working_dir(),
        &startup_info,
        &process_info) != FALSE);
    child_handle_.Reset(process_info.hProcess);
    ::CloseHandle(process_info.hThread);
    set_spawned(true);
    return OVERSEE_TEST;
  }
  # else  // We are not on Windows.
  
  // ForkingDeathTest provides implementations for most of the abstract
  // methods of the DeathTest interface.  Only the AssumeRole method is
  // left undefined.
  class ForkingDeathTest : public DeathTestImpl {
   public:
    ForkingDeathTest(const char* statement, const RE* regex);
  
    // All of these virtual functions are inherited from DeathTest.
    virtual int Wait();
  
   protected:
    void set_child_pid(pid_t child_pid) { child_pid_ = child_pid; }
  
   private:
    // PID of child process during death test; 0 in the child process itself.
    pid_t child_pid_;
  };
  
  // Constructs a ForkingDeathTest.
  ForkingDeathTest::ForkingDeathTest(const char* a_statement, const RE* a_regex)
      : DeathTestImpl(a_statement, a_regex),
        child_pid_(-1) {}
  
  // Waits for the child in a death test to exit, returning its exit
  // status, or 0 if no child process exists.  As a side effect, sets the
  // outcome data member.
  int ForkingDeathTest::Wait() {
    if (!spawned())
      return 0;
  
    ReadAndInterpretStatusByte();
  
    int status_value;
    GTEST_DEATH_TEST_CHECK_SYSCALL_(waitpid(child_pid_, &status_value, 0));
    set_status(status_value);
    return status_value;
  }
  
  // A concrete death test class that forks, then immediately runs the test
  // in the child process.
  class NoExecDeathTest : public ForkingDeathTest {
   public:
    NoExecDeathTest(const char* a_statement, const RE* a_regex) :
        ForkingDeathTest(a_statement, a_regex) { }
    virtual TestRole AssumeRole();
  };
  
  // The AssumeRole process for a fork-and-run death test.  It implements a
  // straightforward fork, with a simple pipe to transmit the status byte.
  DeathTest::TestRole NoExecDeathTest::AssumeRole() {
    const size_t thread_count = GetThreadCount();
    if (thread_count != 1) {
      GTEST_LOG_(WARNING) << DeathTestThreadWarning(thread_count);
    }
  
    int pipe_fd[2];
    GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
  
    DeathTest::set_last_death_test_message("");
    CaptureStderr();
    // When we fork the process below, the log file buffers are copied, but the
    // file descriptors are shared.  We flush all log files here so that closing
    // the file descriptors in the child process doesn't throw off the
    // synchronization between descriptors and buffers in the parent process.
    // This is as close to the fork as possible to avoid a race condition in case
    // there are multiple threads running before the death test, and another
    // thread writes to the log file.
    FlushInfoLog();
  
    const pid_t child_pid = fork();
    GTEST_DEATH_TEST_CHECK_(child_pid != -1);
    set_child_pid(child_pid);
    if (child_pid == 0) {
      GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[0]));
      set_write_fd(pipe_fd[1]);
      // Redirects all logging to stderr in the child process to prevent
      // concurrent writes to the log files.  We capture stderr in the parent
      // process and append the child process' output to a log.
      LogToStderr();
      // Event forwarding to the listeners of event listener API mush be shut
      // down in death test subprocesses.
      GetUnitTestImpl()->listeners()->SuppressEventForwarding();
      g_in_fast_death_test_child = true;
      return EXECUTE_TEST;
    } else {
      GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
      set_read_fd(pipe_fd[0]);
      set_spawned(true);
      return OVERSEE_TEST;
    }
  }
  
  // A concrete death test class that forks and re-executes the main
  // program from the beginning, with command-line flags set that cause
  // only this specific death test to be run.
  class ExecDeathTest : public ForkingDeathTest {
   public:
    ExecDeathTest(const char* a_statement, const RE* a_regex,
                  const char* file, int line) :
        ForkingDeathTest(a_statement, a_regex), file_(file), line_(line) { }
    virtual TestRole AssumeRole();
   private:
    static ::std::vector<testing::internal::string>
    GetArgvsForDeathTestChildProcess() {
      ::std::vector<testing::internal::string> args = GetInjectableArgvs();
  #  if defined(GTEST_EXTRA_DEATH_TEST_COMMAND_LINE_ARGS_)
      ::std::vector<testing::internal::string> extra_args =
          GTEST_EXTRA_DEATH_TEST_COMMAND_LINE_ARGS_();
      args.insert(args.end(), extra_args.begin(), extra_args.end());
  #  endif  // defined(GTEST_EXTRA_DEATH_TEST_COMMAND_LINE_ARGS_)
      return args;
    }
    // The name of the file in which the death test is located.
    const char* const file_;
    // The line number on which the death test is located.
    const int line_;
  };
  
  // Utility class for accumulating command-line arguments.
  class Arguments {
   public:
    Arguments() {
      args_.push_back(NULL);
    }
  
    ~Arguments() {
      for (std::vector<char*>::iterator i = args_.begin(); i != args_.end();
           ++i) {
        free(*i);
      }
    }
    void AddArgument(const char* argument) {
      args_.insert(args_.end() - 1, posix::StrDup(argument));
    }
  
    template <typename Str>
    void AddArguments(const ::std::vector<Str>& arguments) {
      for (typename ::std::vector<Str>::const_iterator i = arguments.begin();
           i != arguments.end();
           ++i) {
        args_.insert(args_.end() - 1, posix::StrDup(i->c_str()));
      }
    }
    char* const* Argv() {
      return &args_[0];
    }
  
   private:
    std::vector<char*> args_;
  };
  
  // A struct that encompasses the arguments to the child process of a
  // threadsafe-style death test process.
  struct ExecDeathTestArgs {
    char* const* argv;  // Command-line arguments for the child's call to exec
    int close_fd;       // File descriptor to close; the read end of a pipe
  };
  
  #  if GTEST_OS_MAC
  inline char** GetEnviron() {
    // When Google Test is built as a framework on MacOS X, the environ variable
    // is unavailable. Apple's documentation (man environ) recommends using
    // _NSGetEnviron() instead.
    return *_NSGetEnviron();
  }
  #  else
  // Some POSIX platforms expect you to declare environ. extern "C" makes
  // it reside in the global namespace.
  extern "C" char** environ;
  inline char** GetEnviron() { return environ; }
  #  endif  // GTEST_OS_MAC
  
  #  if !GTEST_OS_QNX
  // The main function for a threadsafe-style death test child process.
  // This function is called in a clone()-ed process and thus must avoid
  // any potentially unsafe operations like malloc or libc functions.
  static int ExecDeathTestChildMain(void* child_arg) {
    ExecDeathTestArgs* const args = static_cast<ExecDeathTestArgs*>(child_arg);
    GTEST_DEATH_TEST_CHECK_SYSCALL_(close(args->close_fd));
  
    // We need to execute the test program in the same environment where
    // it was originally invoked.  Therefore we change to the original
    // working directory first.
    const char* const original_dir =
        UnitTest::GetInstance()->original_working_dir();
    // We can safely call chdir() as it's a direct system call.
    if (chdir(original_dir) != 0) {
      DeathTestAbort(std::string("chdir(\"") + original_dir + "\") failed: " +
                     GetLastErrnoDescription());
      return EXIT_FAILURE;
    }
  
    // We can safely call execve() as it's a direct system call.  We
    // cannot use execvp() as it's a libc function and thus potentially
    // unsafe.  Since execve() doesn't search the PATH, the user must
    // invoke the test program via a valid path that contains at least
    // one path separator.
    execve(args->argv[0], args->argv, GetEnviron());
    DeathTestAbort(std::string("execve(") + args->argv[0] + ", ...) in " +
                   original_dir + " failed: " +
                   GetLastErrnoDescription());
    return EXIT_FAILURE;
  }
  #  endif  // !GTEST_OS_QNX
  
  // Two utility routines that together determine the direction the stack
  // grows.
  // This could be accomplished more elegantly by a single recursive
  // function, but we want to guard against the unlikely possibility of
  // a smart compiler optimizing the recursion away.
  //
  // GTEST_NO_INLINE_ is required to prevent GCC 4.6 from inlining
  // StackLowerThanAddress into StackGrowsDown, which then doesn't give
  // correct answer.
  void StackLowerThanAddress(const void* ptr, bool* result) GTEST_NO_INLINE_;
  void StackLowerThanAddress(const void* ptr, bool* result) {
    int dummy;
    *result = (&dummy < ptr);
  }
  
  // Make sure AddressSanitizer does not tamper with the stack here.
  GTEST_ATTRIBUTE_NO_SANITIZE_ADDRESS_
  bool StackGrowsDown() {
    int dummy;
    bool result;
    StackLowerThanAddress(&dummy, &result);
    return result;
  }
  
  // Spawns a child process with the same executable as the current process in
  // a thread-safe manner and instructs it to run the death test.  The
  // implementation uses fork(2) + exec.  On systems where clone(2) is
  // available, it is used instead, being slightly more thread-safe.  On QNX,
  // fork supports only single-threaded environments, so this function uses
  // spawn(2) there instead.  The function dies with an error message if
  // anything goes wrong.
  static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) {
    ExecDeathTestArgs args = { argv, close_fd };
    pid_t child_pid = -1;
  
  #  if GTEST_OS_QNX
    // Obtains the current directory and sets it to be closed in the child
    // process.
    const int cwd_fd = open(".", O_RDONLY);
    GTEST_DEATH_TEST_CHECK_(cwd_fd != -1);
    GTEST_DEATH_TEST_CHECK_SYSCALL_(fcntl(cwd_fd, F_SETFD, FD_CLOEXEC));
    // We need to execute the test program in the same environment where
    // it was originally invoked.  Therefore we change to the original
    // working directory first.
    const char* const original_dir =
        UnitTest::GetInstance()->original_working_dir();
    // We can safely call chdir() as it's a direct system call.
    if (chdir(original_dir) != 0) {
      DeathTestAbort(std::string("chdir(\"") + original_dir + "\") failed: " +
                     GetLastErrnoDescription());
      return EXIT_FAILURE;
    }
  
    int fd_flags;
    // Set close_fd to be closed after spawn.
    GTEST_DEATH_TEST_CHECK_SYSCALL_(fd_flags = fcntl(close_fd, F_GETFD));
    GTEST_DEATH_TEST_CHECK_SYSCALL_(fcntl(close_fd, F_SETFD,
                                          fd_flags | FD_CLOEXEC));
    struct inheritance inherit = {0};
    // spawn is a system call.
    child_pid = spawn(args.argv[0], 0, NULL, &inherit, args.argv, GetEnviron());
    // Restores the current working directory.
    GTEST_DEATH_TEST_CHECK_(fchdir(cwd_fd) != -1);
    GTEST_DEATH_TEST_CHECK_SYSCALL_(close(cwd_fd));
  
  #  else   // GTEST_OS_QNX
  #   if GTEST_OS_LINUX
    // When a SIGPROF signal is received while fork() or clone() are executing,
    // the process may hang. To avoid this, we ignore SIGPROF here and re-enable
    // it after the call to fork()/clone() is complete.
    struct sigaction saved_sigprof_action;
    struct sigaction ignore_sigprof_action;
    memset(&ignore_sigprof_action, 0, sizeof(ignore_sigprof_action));
    sigemptyset(&ignore_sigprof_action.sa_mask);
    ignore_sigprof_action.sa_handler = SIG_IGN;
    GTEST_DEATH_TEST_CHECK_SYSCALL_(sigaction(
        SIGPROF, &ignore_sigprof_action, &saved_sigprof_action));
  #   endif  // GTEST_OS_LINUX
  
  #   if GTEST_HAS_CLONE
    const bool use_fork = GTEST_FLAG(death_test_use_fork);
  
    if (!use_fork) {
      static const bool stack_grows_down = StackGrowsDown();
      const size_t stack_size = getpagesize();
      // MMAP_ANONYMOUS is not defined on Mac, so we use MAP_ANON instead.
      void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,
                               MAP_ANON | MAP_PRIVATE, -1, 0);
      GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED);
  
      // Maximum stack alignment in bytes:  For a downward-growing stack, this
      // amount is subtracted from size of the stack space to get an address
      // that is within the stack space and is aligned on all systems we care
      // about.  As far as I know there is no ABI with stack alignment greater
      // than 64.  We assume stack and stack_size already have alignment of
      // kMaxStackAlignment.
      const size_t kMaxStackAlignment = 64;
      void* const stack_top =
          static_cast<char*>(stack) +
              (stack_grows_down ? stack_size - kMaxStackAlignment : 0);
      GTEST_DEATH_TEST_CHECK_(stack_size > kMaxStackAlignment &&
          reinterpret_cast<intptr_t>(stack_top) % kMaxStackAlignment == 0);
  
      child_pid = clone(&ExecDeathTestChildMain, stack_top, SIGCHLD, &args);
  
      GTEST_DEATH_TEST_CHECK_(munmap(stack, stack_size) != -1);
    }
  #   else
    const bool use_fork = true;
  #   endif  // GTEST_HAS_CLONE
  
    if (use_fork && (child_pid = fork()) == 0) {
        ExecDeathTestChildMain(&args);
        _exit(0);
    }
  #  endif  // GTEST_OS_QNX
  #  if GTEST_OS_LINUX
    GTEST_DEATH_TEST_CHECK_SYSCALL_(
        sigaction(SIGPROF, &saved_sigprof_action, NULL));
  #  endif  // GTEST_OS_LINUX
  
    GTEST_DEATH_TEST_CHECK_(child_pid != -1);
    return child_pid;
  }
  
  // The AssumeRole process for a fork-and-exec death test.  It re-executes the
  // main program from the beginning, setting the --gtest_filter
  // and --gtest_internal_run_death_test flags to cause only the current
  // death test to be re-run.
  DeathTest::TestRole ExecDeathTest::AssumeRole() {
    const UnitTestImpl* const impl = GetUnitTestImpl();
    const InternalRunDeathTestFlag* const flag =
        impl->internal_run_death_test_flag();
    const TestInfo* const info = impl->current_test_info();
    const int death_test_index = info->result()->death_test_count();
  
    if (flag != NULL) {
      set_write_fd(flag->write_fd());
      return EXECUTE_TEST;
    }
  
    int pipe_fd[2];
    GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
    // Clear the close-on-exec flag on the write end of the pipe, lest
    // it be closed when the child process does an exec:
    GTEST_DEATH_TEST_CHECK_(fcntl(pipe_fd[1], F_SETFD, 0) != -1);
  
    const std::string filter_flag =
        std::string("--") + GTEST_FLAG_PREFIX_ + kFilterFlag + "="
        + info->test_case_name() + "." + info->name();
    const std::string internal_flag =
        std::string("--") + GTEST_FLAG_PREFIX_ + kInternalRunDeathTestFlag + "="
        + file_ + "|" + StreamableToString(line_) + "|"
        + StreamableToString(death_test_index) + "|"
        + StreamableToString(pipe_fd[1]);
    Arguments args;
    args.AddArguments(GetArgvsForDeathTestChildProcess());
    args.AddArgument(filter_flag.c_str());
    args.AddArgument(internal_flag.c_str());
  
    DeathTest::set_last_death_test_message("");
  
    CaptureStderr();
    // See the comment in NoExecDeathTest::AssumeRole for why the next line
    // is necessary.
    FlushInfoLog();
  
    const pid_t child_pid = ExecDeathTestSpawnChild(args.Argv(), pipe_fd[0]);
    GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
    set_child_pid(child_pid);
    set_read_fd(pipe_fd[0]);
    set_spawned(true);
    return OVERSEE_TEST;
  }
  
  # endif  // !GTEST_OS_WINDOWS
  
  // Creates a concrete DeathTest-derived class that depends on the
  // --gtest_death_test_style flag, and sets the pointer pointed to
  // by the "test" argument to its address.  If the test should be
  // skipped, sets that pointer to NULL.  Returns true, unless the
  // flag is set to an invalid value.
  bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex,
                                       const char* file, int line,
                                       DeathTest** test) {
    UnitTestImpl* const impl = GetUnitTestImpl();
    const InternalRunDeathTestFlag* const flag =
        impl->internal_run_death_test_flag();
    const int death_test_index = impl->current_test_info()
        ->increment_death_test_count();
  
    if (flag != NULL) {
      if (death_test_index > flag->index()) {
        DeathTest::set_last_death_test_message(
            "Death test count (" + StreamableToString(death_test_index)
            + ") somehow exceeded expected maximum ("
            + StreamableToString(flag->index()) + ")");
        return false;
      }
  
      if (!(flag->file() == file && flag->line() == line &&
            flag->index() == death_test_index)) {
        *test = NULL;
        return true;
      }
    }
  
  # if GTEST_OS_WINDOWS
  
    if (GTEST_FLAG(death_test_style) == "threadsafe" ||
        GTEST_FLAG(death_test_style) == "fast") {
      *test = new WindowsDeathTest(statement, regex, file, line);
    }
  
  # else
  
    if (GTEST_FLAG(death_test_style) == "threadsafe") {
      *test = new ExecDeathTest(statement, regex, file, line);
    } else if (GTEST_FLAG(death_test_style) == "fast") {
      *test = new NoExecDeathTest(statement, regex);
    }
  
  # endif  // GTEST_OS_WINDOWS
  
    else {  // NOLINT - this is more readable than unbalanced brackets inside #if.
      DeathTest::set_last_death_test_message(
          "Unknown death test style \"" + GTEST_FLAG(death_test_style)
          + "\" encountered");
      return false;
    }
  
    return true;
  }
  
  # if GTEST_OS_WINDOWS
  // Recreates the pipe and event handles from the provided parameters,
  // signals the event, and returns a file descriptor wrapped around the pipe
  // handle. This function is called in the child process only.
  int GetStatusFileDescriptor(unsigned int parent_process_id,
                              size_t write_handle_as_size_t,
                              size_t event_handle_as_size_t) {
    AutoHandle parent_process_handle(::OpenProcess(PROCESS_DUP_HANDLE,
                                                     FALSE,  // Non-inheritable.
                                                     parent_process_id));
    if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) {
      DeathTestAbort("Unable to open parent process " +
                     StreamableToString(parent_process_id));
    }
  
    // TODO(vladl@google.com): Replace the following check with a
    // compile-time assertion when available.
    GTEST_CHECK_(sizeof(HANDLE) <= sizeof(size_t));
  
    const HANDLE write_handle =
        reinterpret_cast<HANDLE>(write_handle_as_size_t);
    HANDLE dup_write_handle;
  
    // The newly initialized handle is accessible only in in the parent
    // process. To obtain one accessible within the child, we need to use
    // DuplicateHandle.
    if (!::DuplicateHandle(parent_process_handle.Get(), write_handle,
                           ::GetCurrentProcess(), &dup_write_handle,
                           0x0,    // Requested privileges ignored since
                                   // DUPLICATE_SAME_ACCESS is used.
                           FALSE,  // Request non-inheritable handler.
                           DUPLICATE_SAME_ACCESS)) {
      DeathTestAbort("Unable to duplicate the pipe handle " +
                     StreamableToString(write_handle_as_size_t) +
                     " from the parent process " +
                     StreamableToString(parent_process_id));
    }
  
    const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t);
    HANDLE dup_event_handle;
  
    if (!::DuplicateHandle(parent_process_handle.Get(), event_handle,
                           ::GetCurrentProcess(), &dup_event_handle,
                           0x0,
                           FALSE,
                           DUPLICATE_SAME_ACCESS)) {
      DeathTestAbort("Unable to duplicate the event handle " +
                     StreamableToString(event_handle_as_size_t) +
                     " from the parent process " +
                     StreamableToString(parent_process_id));
    }
  
    const int write_fd =
        ::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND);
    if (write_fd == -1) {
      DeathTestAbort("Unable to convert pipe handle " +
                     StreamableToString(write_handle_as_size_t) +
                     " to a file descriptor");
    }
  
    // Signals the parent that the write end of the pipe has been acquired
    // so the parent can release its own write end.
    ::SetEvent(dup_event_handle);
  
    return write_fd;
  }
  # endif  // GTEST_OS_WINDOWS
  
  // Returns a newly created InternalRunDeathTestFlag object with fields
  // initialized from the GTEST_FLAG(internal_run_death_test) flag if
  // the flag is specified; otherwise returns NULL.
  InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {
    if (GTEST_FLAG(internal_run_death_test) == "") return NULL;
  
    // GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we
    // can use it here.
    int line = -1;
    int index = -1;
    ::std::vector< ::std::string> fields;
    SplitString(GTEST_FLAG(internal_run_death_test).c_str(), '|', &fields);
    int write_fd = -1;
  
  # if GTEST_OS_WINDOWS
  
    unsigned int parent_process_id = 0;
    size_t write_handle_as_size_t = 0;
    size_t event_handle_as_size_t = 0;
  
    if (fields.size() != 6
        || !ParseNaturalNumber(fields[1], &line)
        || !ParseNaturalNumber(fields[2], &index)
        || !ParseNaturalNumber(fields[3], &parent_process_id)
        || !ParseNaturalNumber(fields[4], &write_handle_as_size_t)
        || !ParseNaturalNumber(fields[5], &event_handle_as_size_t)) {
      DeathTestAbort("Bad --gtest_internal_run_death_test flag: " +
                     GTEST_FLAG(internal_run_death_test));
    }
    write_fd = GetStatusFileDescriptor(parent_process_id,
                                       write_handle_as_size_t,
                                       event_handle_as_size_t);
  # else
  
    if (fields.size() != 4
        || !ParseNaturalNumber(fields[1], &line)
        || !ParseNaturalNumber(fields[2], &index)
        || !ParseNaturalNumber(fields[3], &write_fd)) {
      DeathTestAbort("Bad --gtest_internal_run_death_test flag: "
          + GTEST_FLAG(internal_run_death_test));
    }
  
  # endif  // GTEST_OS_WINDOWS
  
    return new InternalRunDeathTestFlag(fields[0], line, index, write_fd);
  }
  
  }  // namespace internal
  
  #endif  // GTEST_HAS_DEATH_TEST
  
  }  // namespace testing
  // Copyright 2008, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Authors: keith.ray@gmail.com (Keith Ray)
  
  
  #include <stdlib.h>
  
  #if GTEST_OS_WINDOWS_MOBILE
  # include <windows.h>
  #elif GTEST_OS_WINDOWS
  # include <direct.h>
  # include <io.h>
  #elif GTEST_OS_SYMBIAN
  // Symbian OpenC has PATH_MAX in sys/syslimits.h
  # include <sys/syslimits.h>
  #else
  # include <limits.h>
  # include <climits>  // Some Linux distributions define PATH_MAX here.
  #endif  // GTEST_OS_WINDOWS_MOBILE
  
  #if GTEST_OS_WINDOWS
  # define GTEST_PATH_MAX_ _MAX_PATH
  #elif defined(PATH_MAX)
  # define GTEST_PATH_MAX_ PATH_MAX
  #elif defined(_XOPEN_PATH_MAX)
  # define GTEST_PATH_MAX_ _XOPEN_PATH_MAX
  #else
  # define GTEST_PATH_MAX_ _POSIX_PATH_MAX
  #endif  // GTEST_OS_WINDOWS
  
  
  namespace testing {
  namespace internal {
  
  #if GTEST_OS_WINDOWS
  // On Windows, '\\' is the standard path separator, but many tools and the
  // Windows API also accept '/' as an alternate path separator. Unless otherwise
  // noted, a file path can contain either kind of path separators, or a mixture
  // of them.
  const char kPathSeparator = '\\';
  const char kAlternatePathSeparator = '/';
  const char kAlternatePathSeparatorString[] = "/";
  # if GTEST_OS_WINDOWS_MOBILE
  // Windows CE doesn't have a current directory. You should not use
  // the current directory in tests on Windows CE, but this at least
  // provides a reasonable fallback.
  const char kCurrentDirectoryString[] = "\\";
  // Windows CE doesn't define INVALID_FILE_ATTRIBUTES
  const DWORD kInvalidFileAttributes = 0xffffffff;
  # else
  const char kCurrentDirectoryString[] = ".\\";
  # endif  // GTEST_OS_WINDOWS_MOBILE
  #else
  const char kPathSeparator = '/';
  const char kCurrentDirectoryString[] = "./";
  #endif  // GTEST_OS_WINDOWS
  
  // Returns whether the given character is a valid path separator.
  static bool IsPathSeparator(char c) {
  #if GTEST_HAS_ALT_PATH_SEP_
    return (c == kPathSeparator) || (c == kAlternatePathSeparator);
  #else
    return c == kPathSeparator;
  #endif
  }
  
  // Returns the current working directory, or "" if unsuccessful.
  FilePath FilePath::GetCurrentDir() {
  #if GTEST_OS_WINDOWS_MOBILE || GTEST_OS_WINDOWS_PHONE || GTEST_OS_WINDOWS_RT
    // Windows CE doesn't have a current directory, so we just return
    // something reasonable.
    return FilePath(kCurrentDirectoryString);
  #elif GTEST_OS_WINDOWS
    char cwd[GTEST_PATH_MAX_ + 1] = { '\0' };
    return FilePath(_getcwd(cwd, sizeof(cwd)) == NULL ? "" : cwd);
  #else
    char cwd[GTEST_PATH_MAX_ + 1] = { '\0' };
    char* result = getcwd(cwd, sizeof(cwd));
  # if GTEST_OS_NACL
    // getcwd will likely fail in NaCl due to the sandbox, so return something
    // reasonable. The user may have provided a shim implementation for getcwd,
    // however, so fallback only when failure is detected.
    return FilePath(result == NULL ? kCurrentDirectoryString : cwd);
  # endif  // GTEST_OS_NACL
    return FilePath(result == NULL ? "" : cwd);
  #endif  // GTEST_OS_WINDOWS_MOBILE
  }
  
  // Returns a copy of the FilePath with the case-insensitive extension removed.
  // Example: FilePath("dir/file.exe").RemoveExtension("EXE") returns
  // FilePath("dir/file"). If a case-insensitive extension is not
  // found, returns a copy of the original FilePath.
  FilePath FilePath::RemoveExtension(const char* extension) const {
    const std::string dot_extension = std::string(".") + extension;
    if (String::EndsWithCaseInsensitive(pathname_, dot_extension)) {
      return FilePath(pathname_.substr(
          0, pathname_.length() - dot_extension.length()));
    }
    return *this;
  }
  
  // Returns a pointer to the last occurence of a valid path separator in
  // the FilePath. On Windows, for example, both '/' and '\' are valid path
  // separators. Returns NULL if no path separator was found.
  const char* FilePath::FindLastPathSeparator() const {
    const char* const last_sep = strrchr(c_str(), kPathSeparator);
  #if GTEST_HAS_ALT_PATH_SEP_
    const char* const last_alt_sep = strrchr(c_str(), kAlternatePathSeparator);
    // Comparing two pointers of which only one is NULL is undefined.
    if (last_alt_sep != NULL &&
        (last_sep == NULL || last_alt_sep > last_sep)) {
      return last_alt_sep;
    }
  #endif
    return last_sep;
  }
  
  // Returns a copy of the FilePath with the directory part removed.
  // Example: FilePath("path/to/file").RemoveDirectoryName() returns
  // FilePath("file"). If there is no directory part ("just_a_file"), it returns
  // the FilePath unmodified. If there is no file part ("just_a_dir/") it
  // returns an empty FilePath ("").
  // On Windows platform, '\' is the path separator, otherwise it is '/'.
  FilePath FilePath::RemoveDirectoryName() const {
    const char* const last_sep = FindLastPathSeparator();
    return last_sep ? FilePath(last_sep + 1) : *this;
  }
  
  // RemoveFileName returns the directory path with the filename removed.
  // Example: FilePath("path/to/file").RemoveFileName() returns "path/to/".
  // If the FilePath is "a_file" or "/a_file", RemoveFileName returns
  // FilePath("./") or, on Windows, FilePath(".\\"). If the filepath does
  // not have a file, like "just/a/dir/", it returns the FilePath unmodified.
  // On Windows platform, '\' is the path separator, otherwise it is '/'.
  FilePath FilePath::RemoveFileName() const {
    const char* const last_sep = FindLastPathSeparator();
    std::string dir;
    if (last_sep) {
      dir = std::string(c_str(), last_sep + 1 - c_str());
    } else {
      dir = kCurrentDirectoryString;
    }
    return FilePath(dir);
  }
  
  // Helper functions for naming files in a directory for xml output.
  
  // Given directory = "dir", base_name = "test", number = 0,
  // extension = "xml", returns "dir/test.xml". If number is greater
  // than zero (e.g., 12), returns "dir/test_12.xml".
  // On Windows platform, uses \ as the separator rather than /.
  FilePath FilePath::MakeFileName(const FilePath& directory,
                                  const FilePath& base_name,
                                  int number,
                                  const char* extension) {
    std::string file;
    if (number == 0) {
      file = base_name.string() + "." + extension;
    } else {
      file = base_name.string() + "_" + StreamableToString(number)
          + "." + extension;
    }
    return ConcatPaths(directory, FilePath(file));
  }
  
  // Given directory = "dir", relative_path = "test.xml", returns "dir/test.xml".
  // On Windows, uses \ as the separator rather than /.
  FilePath FilePath::ConcatPaths(const FilePath& directory,
                                 const FilePath& relative_path) {
    if (directory.IsEmpty())
      return relative_path;
    const FilePath dir(directory.RemoveTrailingPathSeparator());
    return FilePath(dir.string() + kPathSeparator + relative_path.string());
  }
  
  // Returns true if pathname describes something findable in the file-system,
  // either a file, directory, or whatever.
  bool FilePath::FileOrDirectoryExists() const {
  #if GTEST_OS_WINDOWS_MOBILE
    LPCWSTR unicode = String::AnsiToUtf16(pathname_.c_str());
    const DWORD attributes = GetFileAttributes(unicode);
    delete [] unicode;
    return attributes != kInvalidFileAttributes;
  #else
    posix::StatStruct file_stat;
    return posix::Stat(pathname_.c_str(), &file_stat) == 0;
  #endif  // GTEST_OS_WINDOWS_MOBILE
  }
  
  // Returns true if pathname describes a directory in the file-system
  // that exists.
  bool FilePath::DirectoryExists() const {
    bool result = false;
  #if GTEST_OS_WINDOWS
    // Don't strip off trailing separator if path is a root directory on
    // Windows (like "C:\\").
    const FilePath& path(IsRootDirectory() ? *this :
                                             RemoveTrailingPathSeparator());
  #else
    const FilePath& path(*this);
  #endif
  
  #if GTEST_OS_WINDOWS_MOBILE
    LPCWSTR unicode = String::AnsiToUtf16(path.c_str());
    const DWORD attributes = GetFileAttributes(unicode);
    delete [] unicode;
    if ((attributes != kInvalidFileAttributes) &&
        (attributes & FILE_ATTRIBUTE_DIRECTORY)) {
      result = true;
    }
  #else
    posix::StatStruct file_stat;
    result = posix::Stat(path.c_str(), &file_stat) == 0 &&
        posix::IsDir(file_stat);
  #endif  // GTEST_OS_WINDOWS_MOBILE
  
    return result;
  }
  
  // Returns true if pathname describes a root directory. (Windows has one
  // root directory per disk drive.)
  bool FilePath::IsRootDirectory() const {
  #if GTEST_OS_WINDOWS
    // TODO(wan@google.com): on Windows a network share like
    // \\server\share can be a root directory, although it cannot be the
    // current directory.  Handle this properly.
    return pathname_.length() == 3 && IsAbsolutePath();
  #else
    return pathname_.length() == 1 && IsPathSeparator(pathname_.c_str()[0]);
  #endif
  }
  
  // Returns true if pathname describes an absolute path.
  bool FilePath::IsAbsolutePath() const {
    const char* const name = pathname_.c_str();
  #if GTEST_OS_WINDOWS
    return pathname_.length() >= 3 &&
       ((name[0] >= 'a' && name[0] <= 'z') ||
        (name[0] >= 'A' && name[0] <= 'Z')) &&
       name[1] == ':' &&
       IsPathSeparator(name[2]);
  #else
    return IsPathSeparator(name[0]);
  #endif
  }
  
  // Returns a pathname for a file that does not currently exist. The pathname
  // will be directory/base_name.extension or
  // directory/base_name_<number>.extension if directory/base_name.extension
  // already exists. The number will be incremented until a pathname is found
  // that does not already exist.
  // Examples: 'dir/foo_test.xml' or 'dir/foo_test_1.xml'.
  // There could be a race condition if two or more processes are calling this
  // function at the same time -- they could both pick the same filename.
  FilePath FilePath::GenerateUniqueFileName(const FilePath& directory,
                                            const FilePath& base_name,
                                            const char* extension) {
    FilePath full_pathname;
    int number = 0;
    do {
      full_pathname.Set(MakeFileName(directory, base_name, number++, extension));
    } while (full_pathname.FileOrDirectoryExists());
    return full_pathname;
  }
  
  // Returns true if FilePath ends with a path separator, which indicates that
  // it is intended to represent a directory. Returns false otherwise.
  // This does NOT check that a directory (or file) actually exists.
  bool FilePath::IsDirectory() const {
    return !pathname_.empty() &&
           IsPathSeparator(pathname_.c_str()[pathname_.length() - 1]);
  }
  
  // Create directories so that path exists. Returns true if successful or if
  // the directories already exist; returns false if unable to create directories
  // for any reason.
  bool FilePath::CreateDirectoriesRecursively() const {
    if (!this->IsDirectory()) {
      return false;
    }
  
    if (pathname_.length() == 0 || this->DirectoryExists()) {
      return true;
    }
  
    const FilePath parent(this->RemoveTrailingPathSeparator().RemoveFileName());
    return parent.CreateDirectoriesRecursively() && this->CreateFolder();
  }
  
  // Create the directory so that path exists. Returns true if successful or
  // if the directory already exists; returns false if unable to create the
  // directory for any reason, including if the parent directory does not
  // exist. Not named "CreateDirectory" because that's a macro on Windows.
  bool FilePath::CreateFolder() const {
  #if GTEST_OS_WINDOWS_MOBILE
    FilePath removed_sep(this->RemoveTrailingPathSeparator());
    LPCWSTR unicode = String::AnsiToUtf16(removed_sep.c_str());
    int result = CreateDirectory(unicode, NULL) ? 0 : -1;
    delete [] unicode;
  #elif GTEST_OS_WINDOWS
    int result = _mkdir(pathname_.c_str());
  #else
    int result = mkdir(pathname_.c_str(), 0777);
  #endif  // GTEST_OS_WINDOWS_MOBILE
  
    if (result == -1) {
      return this->DirectoryExists();  // An error is OK if the directory exists.
    }
    return true;  // No error.
  }
  
  // If input name has a trailing separator character, remove it and return the
  // name, otherwise return the name string unmodified.
  // On Windows platform, uses \ as the separator, other platforms use /.
  FilePath FilePath::RemoveTrailingPathSeparator() const {
    return IsDirectory()
        ? FilePath(pathname_.substr(0, pathname_.length() - 1))
        : *this;
  }
  
  // Removes any redundant separators that might be in the pathname.
  // For example, "bar///foo" becomes "bar/foo". Does not eliminate other
  // redundancies that might be in a pathname involving "." or "..".
  // TODO(wan@google.com): handle Windows network shares (e.g. \\server\share).
  void FilePath::Normalize() {
    if (pathname_.c_str() == NULL) {
      pathname_ = "";
      return;
    }
    const char* src = pathname_.c_str();
    char* const dest = new char[pathname_.length() + 1];
    char* dest_ptr = dest;
    memset(dest_ptr, 0, pathname_.length() + 1);
  
    while (*src != '\0') {
      *dest_ptr = *src;
      if (!IsPathSeparator(*src)) {
        src++;
      } else {
  #if GTEST_HAS_ALT_PATH_SEP_
        if (*dest_ptr == kAlternatePathSeparator) {
          *dest_ptr = kPathSeparator;
        }
  #endif
        while (IsPathSeparator(*src))
          src++;
      }
      dest_ptr++;
    }
    *dest_ptr = '\0';
    pathname_ = dest;
    delete[] dest;
  }
  
  }  // namespace internal
  }  // namespace testing
  // Copyright 2008, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  
  
  #include <limits.h>
  #include <stdlib.h>
  #include <stdio.h>
  #include <string.h>
  #include <fstream>
  
  #if GTEST_OS_WINDOWS
  # include <windows.h>
  # include <io.h>
  # include <sys/stat.h>
  # include <map>  // Used in ThreadLocal.
  #else
  # include <unistd.h>
  #endif  // GTEST_OS_WINDOWS
  
  #if GTEST_OS_MAC
  # include <mach/mach_init.h>
  # include <mach/task.h>
  # include <mach/vm_map.h>
  #endif  // GTEST_OS_MAC
  
  #if GTEST_OS_QNX
  # include <devctl.h>
  # include <fcntl.h>
  # include <sys/procfs.h>
  #endif  // GTEST_OS_QNX
  
  #if GTEST_OS_AIX
  # include <procinfo.h>
  # include <sys/types.h>
  #endif  // GTEST_OS_AIX
  
  
  // Indicates that this translation unit is part of Google Test's
  // implementation.  It must come before gtest-internal-inl.h is
  // included, or there will be a compiler error.  This trick exists to
  // prevent the accidental inclusion of gtest-internal-inl.h in the
  // user's code.
  #define GTEST_IMPLEMENTATION_ 1
  #undef GTEST_IMPLEMENTATION_
  
  namespace testing {
  namespace internal {
  
  #if defined(_MSC_VER) || defined(__BORLANDC__)
  // MSVC and C++Builder do not provide a definition of STDERR_FILENO.
  const int kStdOutFileno = 1;
  const int kStdErrFileno = 2;
  #else
  const int kStdOutFileno = STDOUT_FILENO;
  const int kStdErrFileno = STDERR_FILENO;
  #endif  // _MSC_VER
  
  #if GTEST_OS_LINUX
  
  namespace {
  template <typename T>
  T ReadProcFileField(const string& filename, int field) {
    std::string dummy;
    std::ifstream file(filename.c_str());
    while (field-- > 0) {
      file >> dummy;
    }
    T output = 0;
    file >> output;
    return output;
  }
  }  // namespace
  
  // Returns the number of active threads, or 0 when there is an error.
  size_t GetThreadCount() {
    const string filename =
        (Message() << "/proc/" << getpid() << "/stat").GetString();
    return ReadProcFileField<int>(filename, 19);
  }
  
  #elif GTEST_OS_MAC
  
  size_t GetThreadCount() {
    const task_t task = mach_task_self();
    mach_msg_type_number_t thread_count;
    thread_act_array_t thread_list;
    const kern_return_t status = task_threads(task, &thread_list, &thread_count);
    if (status == KERN_SUCCESS) {
      // task_threads allocates resources in thread_list and we need to free them
      // to avoid leaks.
      vm_deallocate(task,
                    reinterpret_cast<vm_address_t>(thread_list),
                    sizeof(thread_t) * thread_count);
      return static_cast<size_t>(thread_count);
    } else {
      return 0;
    }
  }
  
  #elif GTEST_OS_QNX
  
  // Returns the number of threads running in the process, or 0 to indicate that
  // we cannot detect it.
  size_t GetThreadCount() {
    const int fd = open("/proc/self/as", O_RDONLY);
    if (fd < 0) {
      return 0;
    }
    procfs_info process_info;
    const int status =
        devctl(fd, DCMD_PROC_INFO, &process_info, sizeof(process_info), NULL);
    close(fd);
    if (status == EOK) {
      return static_cast<size_t>(process_info.num_threads);
    } else {
      return 0;
    }
  }
  
  #elif GTEST_OS_AIX
  
  size_t GetThreadCount() {
    struct procentry64 entry;
    pid_t pid = getpid();
    int status = getprocs64(&entry, sizeof(entry), NULL, 0, &pid, 1);
    if (status == 1) {
      return entry.pi_thcount;
    } else {
      return 0;
    }
  }
  
  #else
  
  size_t GetThreadCount() {
    // There's no portable way to detect the number of threads, so we just
    // return 0 to indicate that we cannot detect it.
    return 0;
  }
  
  #endif  // GTEST_OS_LINUX
  
  #if GTEST_IS_THREADSAFE && GTEST_OS_WINDOWS
  
  void SleepMilliseconds(int n) {
    ::Sleep(n);
  }
  
  AutoHandle::AutoHandle()
      : handle_(INVALID_HANDLE_VALUE) {}
  
  AutoHandle::AutoHandle(Handle handle)
      : handle_(handle) {}
  
  AutoHandle::~AutoHandle() {
    Reset();
  }
  
  AutoHandle::Handle AutoHandle::Get() const {
    return handle_;
  }
  
  void AutoHandle::Reset() {
    Reset(INVALID_HANDLE_VALUE);
  }
  
  void AutoHandle::Reset(HANDLE handle) {
    // Resetting with the same handle we already own is invalid.
    if (handle_ != handle) {
      if (IsCloseable()) {
        ::CloseHandle(handle_);
      }
      handle_ = handle;
    } else {
      GTEST_CHECK_(!IsCloseable())
          << "Resetting a valid handle to itself is likely a programmer error "
              "and thus not allowed.";
    }
  }
  
  bool AutoHandle::IsCloseable() const {
    // Different Windows APIs may use either of these values to represent an
    // invalid handle.
    return handle_ != NULL && handle_ != INVALID_HANDLE_VALUE;
  }
  
  Notification::Notification()
      : event_(::CreateEvent(NULL,   // Default security attributes.
                             TRUE,   // Do not reset automatically.
                             FALSE,  // Initially unset.
                             NULL)) {  // Anonymous event.
    GTEST_CHECK_(event_.Get() != NULL);
  }
  
  void Notification::Notify() {
    GTEST_CHECK_(::SetEvent(event_.Get()) != FALSE);
  }
  
  void Notification::WaitForNotification() {
    GTEST_CHECK_(
        ::WaitForSingleObject(event_.Get(), INFINITE) == WAIT_OBJECT_0);
  }
  
  Mutex::Mutex()
      : owner_thread_id_(0),
        type_(kDynamic),
        critical_section_init_phase_(0),
        critical_section_(new CRITICAL_SECTION) {
    ::InitializeCriticalSection(critical_section_);
  }
  
  Mutex::~Mutex() {
    // Static mutexes are leaked intentionally. It is not thread-safe to try
    // to clean them up.
    // TODO(yukawa): Switch to Slim Reader/Writer (SRW) Locks, which requires
    // nothing to clean it up but is available only on Vista and later.
    // http://msdn.microsoft.com/en-us/library/windows/desktop/aa904937.aspx
    if (type_ == kDynamic) {
      ::DeleteCriticalSection(critical_section_);
      delete critical_section_;
      critical_section_ = NULL;
    }
  }
  
  void Mutex::Lock() {
    ThreadSafeLazyInit();
    ::EnterCriticalSection(critical_section_);
    owner_thread_id_ = ::GetCurrentThreadId();
  }
  
  void Mutex::Unlock() {
    ThreadSafeLazyInit();
    // We don't protect writing to owner_thread_id_ here, as it's the
    // caller's responsibility to ensure that the current thread holds the
    // mutex when this is called.
    owner_thread_id_ = 0;
    ::LeaveCriticalSection(critical_section_);
  }
  
  // Does nothing if the current thread holds the mutex. Otherwise, crashes
  // with high probability.
  void Mutex::AssertHeld() {
    ThreadSafeLazyInit();
    GTEST_CHECK_(owner_thread_id_ == ::GetCurrentThreadId())
        << "The current thread is not holding the mutex @" << this;
  }
  
  // Initializes owner_thread_id_ and critical_section_ in static mutexes.
  void Mutex::ThreadSafeLazyInit() {
    // Dynamic mutexes are initialized in the constructor.
    if (type_ == kStatic) {
      switch (
          ::InterlockedCompareExchange(&critical_section_init_phase_, 1L, 0L)) {
        case 0:
          // If critical_section_init_phase_ was 0 before the exchange, we
          // are the first to test it and need to perform the initialization.
          owner_thread_id_ = 0;
          critical_section_ = new CRITICAL_SECTION;
          ::InitializeCriticalSection(critical_section_);
          // Updates the critical_section_init_phase_ to 2 to signal
          // initialization complete.
          GTEST_CHECK_(::InterlockedCompareExchange(
                            &critical_section_init_phase_, 2L, 1L) ==
                        1L);
          break;
        case 1:
          // Somebody else is already initializing the mutex; spin until they
          // are done.
          while (::InterlockedCompareExchange(&critical_section_init_phase_,
                                              2L,
                                              2L) != 2L) {
            // Possibly yields the rest of the thread's time slice to other
            // threads.
            ::Sleep(0);
          }
          break;
  
        case 2:
          break;  // The mutex is already initialized and ready for use.
  
        default:
          GTEST_CHECK_(false)
              << "Unexpected value of critical_section_init_phase_ "
              << "while initializing a static mutex.";
      }
    }
  }
  
  namespace {
  
  class ThreadWithParamSupport : public ThreadWithParamBase {
   public:
    static HANDLE CreateThread(Runnable* runnable,
                               Notification* thread_can_start) {
      ThreadMainParam* param = new ThreadMainParam(runnable, thread_can_start);
      DWORD thread_id;
      // TODO(yukawa): Consider to use _beginthreadex instead.
      HANDLE thread_handle = ::CreateThread(
          NULL,    // Default security.
          0,       // Default stack size.
          &ThreadWithParamSupport::ThreadMain,
          param,   // Parameter to ThreadMainStatic
          0x0,     // Default creation flags.
          &thread_id);  // Need a valid pointer for the call to work under Win98.
      GTEST_CHECK_(thread_handle != NULL) << "CreateThread failed with error "
                                          << ::GetLastError() << ".";
      if (thread_handle == NULL) {
        delete param;
      }
      return thread_handle;
    }
  
   private:
    struct ThreadMainParam {
      ThreadMainParam(Runnable* runnable, Notification* thread_can_start)
          : runnable_(runnable),
            thread_can_start_(thread_can_start) {
      }
      scoped_ptr<Runnable> runnable_;
      // Does not own.
      Notification* thread_can_start_;
    };
  
    static DWORD WINAPI ThreadMain(void* ptr) {
      // Transfers ownership.
      scoped_ptr<ThreadMainParam> param(static_cast<ThreadMainParam*>(ptr));
      if (param->thread_can_start_ != NULL)
        param->thread_can_start_->WaitForNotification();
      param->runnable_->Run();
      return 0;
    }
  
    // Prohibit instantiation.
    ThreadWithParamSupport();
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(ThreadWithParamSupport);
  };
  
  }  // namespace
  
  ThreadWithParamBase::ThreadWithParamBase(Runnable *runnable,
                                           Notification* thread_can_start)
        : thread_(ThreadWithParamSupport::CreateThread(runnable,
                                                       thread_can_start)) {
  }
  
  ThreadWithParamBase::~ThreadWithParamBase() {
    Join();
  }
  
  void ThreadWithParamBase::Join() {
    GTEST_CHECK_(::WaitForSingleObject(thread_.Get(), INFINITE) == WAIT_OBJECT_0)
        << "Failed to join the thread with error " << ::GetLastError() << ".";
  }
  
  // Maps a thread to a set of ThreadIdToThreadLocals that have values
  // instantiated on that thread and notifies them when the thread exits.  A
  // ThreadLocal instance is expected to persist until all threads it has
  // values on have terminated.
  class ThreadLocalRegistryImpl {
   public:
    // Registers thread_local_instance as having value on the current thread.
    // Returns a value that can be used to identify the thread from other threads.
    static ThreadLocalValueHolderBase* GetValueOnCurrentThread(
        const ThreadLocalBase* thread_local_instance) {
      DWORD current_thread = ::GetCurrentThreadId();
      MutexLock lock(&mutex_);
      ThreadIdToThreadLocals* const thread_to_thread_locals =
          GetThreadLocalsMapLocked();
      ThreadIdToThreadLocals::iterator thread_local_pos =
          thread_to_thread_locals->find(current_thread);
      if (thread_local_pos == thread_to_thread_locals->end()) {
        thread_local_pos = thread_to_thread_locals->insert(
            std::make_pair(current_thread, ThreadLocalValues())).first;
        StartWatcherThreadFor(current_thread);
      }
      ThreadLocalValues& thread_local_values = thread_local_pos->second;
      ThreadLocalValues::iterator value_pos =
          thread_local_values.find(thread_local_instance);
      if (value_pos == thread_local_values.end()) {
        value_pos =
            thread_local_values
                .insert(std::make_pair(
                    thread_local_instance,
                    linked_ptr<ThreadLocalValueHolderBase>(
                        thread_local_instance->NewValueForCurrentThread())))
                .first;
      }
      return value_pos->second.get();
    }
  
    static void OnThreadLocalDestroyed(
        const ThreadLocalBase* thread_local_instance) {
      std::vector<linked_ptr<ThreadLocalValueHolderBase> > value_holders;
      // Clean up the ThreadLocalValues data structure while holding the lock, but
      // defer the destruction of the ThreadLocalValueHolderBases.
      {
        MutexLock lock(&mutex_);
        ThreadIdToThreadLocals* const thread_to_thread_locals =
            GetThreadLocalsMapLocked();
        for (ThreadIdToThreadLocals::iterator it =
            thread_to_thread_locals->begin();
            it != thread_to_thread_locals->end();
            ++it) {
          ThreadLocalValues& thread_local_values = it->second;
          ThreadLocalValues::iterator value_pos =
              thread_local_values.find(thread_local_instance);
          if (value_pos != thread_local_values.end()) {
            value_holders.push_back(value_pos->second);
            thread_local_values.erase(value_pos);
            // This 'if' can only be successful at most once, so theoretically we
            // could break out of the loop here, but we don't bother doing so.
          }
        }
      }
      // Outside the lock, let the destructor for 'value_holders' deallocate the
      // ThreadLocalValueHolderBases.
    }
  
    static void OnThreadExit(DWORD thread_id) {
      GTEST_CHECK_(thread_id != 0) << ::GetLastError();
      std::vector<linked_ptr<ThreadLocalValueHolderBase> > value_holders;
      // Clean up the ThreadIdToThreadLocals data structure while holding the
      // lock, but defer the destruction of the ThreadLocalValueHolderBases.
      {
        MutexLock lock(&mutex_);
        ThreadIdToThreadLocals* const thread_to_thread_locals =
            GetThreadLocalsMapLocked();
        ThreadIdToThreadLocals::iterator thread_local_pos =
            thread_to_thread_locals->find(thread_id);
        if (thread_local_pos != thread_to_thread_locals->end()) {
          ThreadLocalValues& thread_local_values = thread_local_pos->second;
          for (ThreadLocalValues::iterator value_pos =
              thread_local_values.begin();
              value_pos != thread_local_values.end();
              ++value_pos) {
            value_holders.push_back(value_pos->second);
          }
          thread_to_thread_locals->erase(thread_local_pos);
        }
      }
      // Outside the lock, let the destructor for 'value_holders' deallocate the
      // ThreadLocalValueHolderBases.
    }
  
   private:
    // In a particular thread, maps a ThreadLocal object to its value.
    typedef std::map<const ThreadLocalBase*,
                     linked_ptr<ThreadLocalValueHolderBase> > ThreadLocalValues;
    // Stores all ThreadIdToThreadLocals having values in a thread, indexed by
    // thread's ID.
    typedef std::map<DWORD, ThreadLocalValues> ThreadIdToThreadLocals;
  
    // Holds the thread id and thread handle that we pass from
    // StartWatcherThreadFor to WatcherThreadFunc.
    typedef std::pair<DWORD, HANDLE> ThreadIdAndHandle;
  
    static void StartWatcherThreadFor(DWORD thread_id) {
      // The returned handle will be kept in thread_map and closed by
      // watcher_thread in WatcherThreadFunc.
      HANDLE thread = ::OpenThread(SYNCHRONIZE | THREAD_QUERY_INFORMATION,
                                   FALSE,
                                   thread_id);
      GTEST_CHECK_(thread != NULL);
      // We need to to pass a valid thread ID pointer into CreateThread for it
      // to work correctly under Win98.
      DWORD watcher_thread_id;
      HANDLE watcher_thread = ::CreateThread(
          NULL,   // Default security.
          0,      // Default stack size
          &ThreadLocalRegistryImpl::WatcherThreadFunc,
          reinterpret_cast<LPVOID>(new ThreadIdAndHandle(thread_id, thread)),
          CREATE_SUSPENDED,
          &watcher_thread_id);
      GTEST_CHECK_(watcher_thread != NULL);
      // Give the watcher thread the same priority as ours to avoid being
      // blocked by it.
      ::SetThreadPriority(watcher_thread,
                          ::GetThreadPriority(::GetCurrentThread()));
      ::ResumeThread(watcher_thread);
      ::CloseHandle(watcher_thread);
    }
  
    // Monitors exit from a given thread and notifies those
    // ThreadIdToThreadLocals about thread termination.
    static DWORD WINAPI WatcherThreadFunc(LPVOID param) {
      const ThreadIdAndHandle* tah =
          reinterpret_cast<const ThreadIdAndHandle*>(param);
      GTEST_CHECK_(
          ::WaitForSingleObject(tah->second, INFINITE) == WAIT_OBJECT_0);
      OnThreadExit(tah->first);
      ::CloseHandle(tah->second);
      delete tah;
      return 0;
    }
  
    // Returns map of thread local instances.
    static ThreadIdToThreadLocals* GetThreadLocalsMapLocked() {
      mutex_.AssertHeld();
      static ThreadIdToThreadLocals* map = new ThreadIdToThreadLocals;
      return map;
    }
  
    // Protects access to GetThreadLocalsMapLocked() and its return value.
    static Mutex mutex_;
    // Protects access to GetThreadMapLocked() and its return value.
    static Mutex thread_map_mutex_;
  };
  
  Mutex ThreadLocalRegistryImpl::mutex_(Mutex::kStaticMutex);
  Mutex ThreadLocalRegistryImpl::thread_map_mutex_(Mutex::kStaticMutex);
  
  ThreadLocalValueHolderBase* ThreadLocalRegistry::GetValueOnCurrentThread(
        const ThreadLocalBase* thread_local_instance) {
    return ThreadLocalRegistryImpl::GetValueOnCurrentThread(
        thread_local_instance);
  }
  
  void ThreadLocalRegistry::OnThreadLocalDestroyed(
        const ThreadLocalBase* thread_local_instance) {
    ThreadLocalRegistryImpl::OnThreadLocalDestroyed(thread_local_instance);
  }
  
  #endif  // GTEST_IS_THREADSAFE && GTEST_OS_WINDOWS
  
  #if GTEST_USES_POSIX_RE
  
  // Implements RE.  Currently only needed for death tests.
  
  RE::~RE() {
    if (is_valid_) {
      // regfree'ing an invalid regex might crash because the content
      // of the regex is undefined. Since the regex's are essentially
      // the same, one cannot be valid (or invalid) without the other
      // being so too.
      regfree(&partial_regex_);
      regfree(&full_regex_);
    }
    free(const_cast<char*>(pattern_));
  }
  
  // Returns true iff regular expression re matches the entire str.
  bool RE::FullMatch(const char* str, const RE& re) {
    if (!re.is_valid_) return false;
  
    regmatch_t match;
    return regexec(&re.full_regex_, str, 1, &match, 0) == 0;
  }
  
  // Returns true iff regular expression re matches a substring of str
  // (including str itself).
  bool RE::PartialMatch(const char* str, const RE& re) {
    if (!re.is_valid_) return false;
  
    regmatch_t match;
    return regexec(&re.partial_regex_, str, 1, &match, 0) == 0;
  }
  
  // Initializes an RE from its string representation.
  void RE::Init(const char* regex) {
    pattern_ = posix::StrDup(regex);
  
    // Reserves enough bytes to hold the regular expression used for a
    // full match.
    const size_t full_regex_len = strlen(regex) + 10;
    char* const full_pattern = new char[full_regex_len];
  
    snprintf(full_pattern, full_regex_len, "^(%s)$", regex);
    is_valid_ = regcomp(&full_regex_, full_pattern, REG_EXTENDED) == 0;
    // We want to call regcomp(&partial_regex_, ...) even if the
    // previous expression returns false.  Otherwise partial_regex_ may
    // not be properly initialized can may cause trouble when it's
    // freed.
    //
    // Some implementation of POSIX regex (e.g. on at least some
    // versions of Cygwin) doesn't accept the empty string as a valid
    // regex.  We change it to an equivalent form "()" to be safe.
    if (is_valid_) {
      const char* const partial_regex = (*regex == '\0') ? "()" : regex;
      is_valid_ = regcomp(&partial_regex_, partial_regex, REG_EXTENDED) == 0;
    }
    EXPECT_TRUE(is_valid_)
        << "Regular expression \"" << regex
        << "\" is not a valid POSIX Extended regular expression.";
  
    delete[] full_pattern;
  }
  
  #elif GTEST_USES_SIMPLE_RE
  
  // Returns true iff ch appears anywhere in str (excluding the
  // terminating '\0' character).
  bool IsInSet(char ch, const char* str) {
    return ch != '\0' && strchr(str, ch) != NULL;
  }
  
  // Returns true iff ch belongs to the given classification.  Unlike
  // similar functions in <ctype.h>, these aren't affected by the
  // current locale.
  bool IsAsciiDigit(char ch) { return '0' <= ch && ch <= '9'; }
  bool IsAsciiPunct(char ch) {
    return IsInSet(ch, "^-!\"#$%&'()*+,./:;<=>?@[\\]_`{|}~");
  }
  bool IsRepeat(char ch) { return IsInSet(ch, "?*+"); }
  bool IsAsciiWhiteSpace(char ch) { return IsInSet(ch, " \f\n\r\t\v"); }
  bool IsAsciiWordChar(char ch) {
    return ('a' <= ch && ch <= 'z') || ('A' <= ch && ch <= 'Z') ||
        ('0' <= ch && ch <= '9') || ch == '_';
  }
  
  // Returns true iff "\\c" is a supported escape sequence.
  bool IsValidEscape(char c) {
    return (IsAsciiPunct(c) || IsInSet(c, "dDfnrsStvwW"));
  }
  
  // Returns true iff the given atom (specified by escaped and pattern)
  // matches ch.  The result is undefined if the atom is invalid.
  bool AtomMatchesChar(bool escaped, char pattern_char, char ch) {
    if (escaped) {  // "\\p" where p is pattern_char.
      switch (pattern_char) {
        case 'd': return IsAsciiDigit(ch);
        case 'D': return !IsAsciiDigit(ch);
        case 'f': return ch == '\f';
        case 'n': return ch == '\n';
        case 'r': return ch == '\r';
        case 's': return IsAsciiWhiteSpace(ch);
        case 'S': return !IsAsciiWhiteSpace(ch);
        case 't': return ch == '\t';
        case 'v': return ch == '\v';
        case 'w': return IsAsciiWordChar(ch);
        case 'W': return !IsAsciiWordChar(ch);
      }
      return IsAsciiPunct(pattern_char) && pattern_char == ch;
    }
  
    return (pattern_char == '.' && ch != '\n') || pattern_char == ch;
  }
  
  // Helper function used by ValidateRegex() to format error messages.
  std::string FormatRegexSyntaxError(const char* regex, int index) {
    return (Message() << "Syntax error at index " << index
            << " in simple regular expression \"" << regex << "\": ").GetString();
  }
  
  // Generates non-fatal failures and returns false if regex is invalid;
  // otherwise returns true.
  bool ValidateRegex(const char* regex) {
    if (regex == NULL) {
      // TODO(wan@google.com): fix the source file location in the
      // assertion failures to match where the regex is used in user
      // code.
      ADD_FAILURE() << "NULL is not a valid simple regular expression.";
      return false;
    }
  
    bool is_valid = true;
  
    // True iff ?, *, or + can follow the previous atom.
    bool prev_repeatable = false;
    for (int i = 0; regex[i]; i++) {
      if (regex[i] == '\\') {  // An escape sequence
        i++;
        if (regex[i] == '\0') {
          ADD_FAILURE() << FormatRegexSyntaxError(regex, i - 1)
                        << "'\\' cannot appear at the end.";
          return false;
        }
  
        if (!IsValidEscape(regex[i])) {
          ADD_FAILURE() << FormatRegexSyntaxError(regex, i - 1)
                        << "invalid escape sequence \"\\" << regex[i] << "\".";
          is_valid = false;
        }
        prev_repeatable = true;
      } else {  // Not an escape sequence.
        const char ch = regex[i];
  
        if (ch == '^' && i > 0) {
          ADD_FAILURE() << FormatRegexSyntaxError(regex, i)
                        << "'^' can only appear at the beginning.";
          is_valid = false;
        } else if (ch == '$' && regex[i + 1] != '\0') {
          ADD_FAILURE() << FormatRegexSyntaxError(regex, i)
                        << "'$' can only appear at the end.";
          is_valid = false;
        } else if (IsInSet(ch, "()[]{}|")) {
          ADD_FAILURE() << FormatRegexSyntaxError(regex, i)
                        << "'" << ch << "' is unsupported.";
          is_valid = false;
        } else if (IsRepeat(ch) && !prev_repeatable) {
          ADD_FAILURE() << FormatRegexSyntaxError(regex, i)
                        << "'" << ch << "' can only follow a repeatable token.";
          is_valid = false;
        }
  
        prev_repeatable = !IsInSet(ch, "^$?*+");
      }
    }
  
    return is_valid;
  }
  
  // Matches a repeated regex atom followed by a valid simple regular
  // expression.  The regex atom is defined as c if escaped is false,
  // or \c otherwise.  repeat is the repetition meta character (?, *,
  // or +).  The behavior is undefined if str contains too many
  // characters to be indexable by size_t, in which case the test will
  // probably time out anyway.  We are fine with this limitation as
  // std::string has it too.
  bool MatchRepetitionAndRegexAtHead(
      bool escaped, char c, char repeat, const char* regex,
      const char* str) {
    const size_t min_count = (repeat == '+') ? 1 : 0;
    const size_t max_count = (repeat == '?') ? 1 :
        static_cast<size_t>(-1) - 1;
    // We cannot call numeric_limits::max() as it conflicts with the
    // max() macro on Windows.
  
    for (size_t i = 0; i <= max_count; ++i) {
      // We know that the atom matches each of the first i characters in str.
      if (i >= min_count && MatchRegexAtHead(regex, str + i)) {
        // We have enough matches at the head, and the tail matches too.
        // Since we only care about *whether* the pattern matches str
        // (as opposed to *how* it matches), there is no need to find a
        // greedy match.
        return true;
      }
      if (str[i] == '\0' || !AtomMatchesChar(escaped, c, str[i]))
        return false;
    }
    return false;
  }
  
  // Returns true iff regex matches a prefix of str.  regex must be a
  // valid simple regular expression and not start with "^", or the
  // result is undefined.
  bool MatchRegexAtHead(const char* regex, const char* str) {
    if (*regex == '\0')  // An empty regex matches a prefix of anything.
      return true;
  
    // "$" only matches the end of a string.  Note that regex being
    // valid guarantees that there's nothing after "$" in it.
    if (*regex == '$')
      return *str == '\0';
  
    // Is the first thing in regex an escape sequence?
    const bool escaped = *regex == '\\';
    if (escaped)
      ++regex;
    if (IsRepeat(regex[1])) {
      // MatchRepetitionAndRegexAtHead() calls MatchRegexAtHead(), so
      // here's an indirect recursion.  It terminates as the regex gets
      // shorter in each recursion.
      return MatchRepetitionAndRegexAtHead(
          escaped, regex[0], regex[1], regex + 2, str);
    } else {
      // regex isn't empty, isn't "$", and doesn't start with a
      // repetition.  We match the first atom of regex with the first
      // character of str and recurse.
      return (*str != '\0') && AtomMatchesChar(escaped, *regex, *str) &&
          MatchRegexAtHead(regex + 1, str + 1);
    }
  }
  
  // Returns true iff regex matches any substring of str.  regex must be
  // a valid simple regular expression, or the result is undefined.
  //
  // The algorithm is recursive, but the recursion depth doesn't exceed
  // the regex length, so we won't need to worry about running out of
  // stack space normally.  In rare cases the time complexity can be
  // exponential with respect to the regex length + the string length,
  // but usually it's must faster (often close to linear).
  bool MatchRegexAnywhere(const char* regex, const char* str) {
    if (regex == NULL || str == NULL)
      return false;
  
    if (*regex == '^')
      return MatchRegexAtHead(regex + 1, str);
  
    // A successful match can be anywhere in str.
    do {
      if (MatchRegexAtHead(regex, str))
        return true;
    } while (*str++ != '\0');
    return false;
  }
  
  // Implements the RE class.
  
  RE::~RE() {
    free(const_cast<char*>(pattern_));
    free(const_cast<char*>(full_pattern_));
  }
  
  // Returns true iff regular expression re matches the entire str.
  bool RE::FullMatch(const char* str, const RE& re) {
    return re.is_valid_ && MatchRegexAnywhere(re.full_pattern_, str);
  }
  
  // Returns true iff regular expression re matches a substring of str
  // (including str itself).
  bool RE::PartialMatch(const char* str, const RE& re) {
    return re.is_valid_ && MatchRegexAnywhere(re.pattern_, str);
  }
  
  // Initializes an RE from its string representation.
  void RE::Init(const char* regex) {
    pattern_ = full_pattern_ = NULL;
    if (regex != NULL) {
      pattern_ = posix::StrDup(regex);
    }
  
    is_valid_ = ValidateRegex(regex);
    if (!is_valid_) {
      // No need to calculate the full pattern when the regex is invalid.
      return;
    }
  
    const size_t len = strlen(regex);
    // Reserves enough bytes to hold the regular expression used for a
    // full match: we need space to prepend a '^', append a '$', and
    // terminate the string with '\0'.
    char* buffer = static_cast<char*>(malloc(len + 3));
    full_pattern_ = buffer;
  
    if (*regex != '^')
      *buffer++ = '^';  // Makes sure full_pattern_ starts with '^'.
  
    // We don't use snprintf or strncpy, as they trigger a warning when
    // compiled with VC++ 8.0.
    memcpy(buffer, regex, len);
    buffer += len;
  
    if (len == 0 || regex[len - 1] != '$')
      *buffer++ = '$';  // Makes sure full_pattern_ ends with '$'.
  
    *buffer = '\0';
  }
  
  #endif  // GTEST_USES_POSIX_RE
  
  const char kUnknownFile[] = "unknown file";
  
  // Formats a source file path and a line number as they would appear
  // in an error message from the compiler used to compile this code.
  GTEST_API_ ::std::string FormatFileLocation(const char* file, int line) {
    const std::string file_name(file == NULL ? kUnknownFile : file);
  
    if (line < 0) {
      return file_name + ":";
    }
  #ifdef _MSC_VER
    return file_name + "(" + StreamableToString(line) + "):";
  #else
    return file_name + ":" + StreamableToString(line) + ":";
  #endif  // _MSC_VER
  }
  
  // Formats a file location for compiler-independent XML output.
  // Although this function is not platform dependent, we put it next to
  // FormatFileLocation in order to contrast the two functions.
  // Note that FormatCompilerIndependentFileLocation() does NOT append colon
  // to the file location it produces, unlike FormatFileLocation().
  GTEST_API_ ::std::string FormatCompilerIndependentFileLocation(
      const char* file, int line) {
    const std::string file_name(file == NULL ? kUnknownFile : file);
  
    if (line < 0)
      return file_name;
    else
      return file_name + ":" + StreamableToString(line);
  }
  
  GTestLog::GTestLog(GTestLogSeverity severity, const char* file, int line)
      : severity_(severity) {
    const char* const marker =
        severity == GTEST_INFO ?    "[  INFO ]" :
        severity == GTEST_WARNING ? "[WARNING]" :
        severity == GTEST_ERROR ?   "[ ERROR ]" : "[ FATAL ]";
    GetStream() << ::std::endl << marker << " "
                << FormatFileLocation(file, line).c_str() << ": ";
  }
  
  // Flushes the buffers and, if severity is GTEST_FATAL, aborts the program.
  GTestLog::~GTestLog() {
    GetStream() << ::std::endl;
    if (severity_ == GTEST_FATAL) {
      fflush(stderr);
      posix::Abort();
    }
  }
  // Disable Microsoft deprecation warnings for POSIX functions called from
  // this class (creat, dup, dup2, and close)
  GTEST_DISABLE_MSC_WARNINGS_PUSH_(4996)
  
  #if GTEST_HAS_STREAM_REDIRECTION
  
  // Object that captures an output stream (stdout/stderr).
  class CapturedStream {
   public:
    // The ctor redirects the stream to a temporary file.
    explicit CapturedStream(int fd) : fd_(fd), uncaptured_fd_(dup(fd)) {
  # if GTEST_OS_WINDOWS
      char temp_dir_path[MAX_PATH + 1] = { '\0' };  // NOLINT
      char temp_file_path[MAX_PATH + 1] = { '\0' };  // NOLINT
  
      ::GetTempPathA(sizeof(temp_dir_path), temp_dir_path);
      const UINT success = ::GetTempFileNameA(temp_dir_path,
                                              "gtest_redir",
                                              0,  // Generate unique file name.
                                              temp_file_path);
      GTEST_CHECK_(success != 0)
          << "Unable to create a temporary file in " << temp_dir_path;
      const int captured_fd = creat(temp_file_path, _S_IREAD | _S_IWRITE);
      GTEST_CHECK_(captured_fd != -1) << "Unable to open temporary file "
                                      << temp_file_path;
      filename_ = temp_file_path;
  # else
      // There's no guarantee that a test has write access to the current
      // directory, so we create the temporary file in the /tmp directory
      // instead. We use /tmp on most systems, and /sdcard on Android.
      // That's because Android doesn't have /tmp.
  #  if GTEST_OS_LINUX_ANDROID
      // Note: Android applications are expected to call the framework's
      // Context.getExternalStorageDirectory() method through JNI to get
      // the location of the world-writable SD Card directory. However,
      // this requires a Context handle, which cannot be retrieved
      // globally from native code. Doing so also precludes running the
      // code as part of a regular standalone executable, which doesn't
      // run in a Dalvik process (e.g. when running it through 'adb shell').
      //
      // The location /sdcard is directly accessible from native code
      // and is the only location (unofficially) supported by the Android
      // team. It's generally a symlink to the real SD Card mount point
      // which can be /mnt/sdcard, /mnt/sdcard0, /system/media/sdcard, or
      // other OEM-customized locations. Never rely on these, and always
      // use /sdcard.
      char name_template[] = "/sdcard/gtest_captured_stream.XXXXXX";
  #  else
      char name_template[] = "/tmp/captured_stream.XXXXXX";
  #  endif  // GTEST_OS_LINUX_ANDROID
      const int captured_fd = mkstemp(name_template);
      filename_ = name_template;
  # endif  // GTEST_OS_WINDOWS
      fflush(NULL);
      dup2(captured_fd, fd_);
      close(captured_fd);
    }
  
    ~CapturedStream() {
      remove(filename_.c_str());
    }
  
    std::string GetCapturedString() {
      if (uncaptured_fd_ != -1) {
        // Restores the original stream.
        fflush(NULL);
        dup2(uncaptured_fd_, fd_);
        close(uncaptured_fd_);
        uncaptured_fd_ = -1;
      }
  
      FILE* const file = posix::FOpen(filename_.c_str(), "r");
      const std::string content = ReadEntireFile(file);
      posix::FClose(file);
      return content;
    }
  
   private:
    const int fd_;  // A stream to capture.
    int uncaptured_fd_;
    // Name of the temporary file holding the stderr output.
    ::std::string filename_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(CapturedStream);
  };
  
  GTEST_DISABLE_MSC_WARNINGS_POP_()
  
  static CapturedStream* g_captured_stderr = NULL;
  static CapturedStream* g_captured_stdout = NULL;
  
  // Starts capturing an output stream (stdout/stderr).
  void CaptureStream(int fd, const char* stream_name, CapturedStream** stream) {
    if (*stream != NULL) {
      GTEST_LOG_(FATAL) << "Only one " << stream_name
                        << " capturer can exist at a time.";
    }
    *stream = new CapturedStream(fd);
  }
  
  // Stops capturing the output stream and returns the captured string.
  std::string GetCapturedStream(CapturedStream** captured_stream) {
    const std::string content = (*captured_stream)->GetCapturedString();
  
    delete *captured_stream;
    *captured_stream = NULL;
  
    return content;
  }
  
  // Starts capturing stdout.
  void CaptureStdout() {
    CaptureStream(kStdOutFileno, "stdout", &g_captured_stdout);
  }
  
  // Starts capturing stderr.
  void CaptureStderr() {
    CaptureStream(kStdErrFileno, "stderr", &g_captured_stderr);
  }
  
  // Stops capturing stdout and returns the captured string.
  std::string GetCapturedStdout() {
    return GetCapturedStream(&g_captured_stdout);
  }
  
  // Stops capturing stderr and returns the captured string.
  std::string GetCapturedStderr() {
    return GetCapturedStream(&g_captured_stderr);
  }
  
  #endif  // GTEST_HAS_STREAM_REDIRECTION
  
  std::string TempDir() {
  #if GTEST_OS_WINDOWS_MOBILE
    return "\\temp\\";
  #elif GTEST_OS_WINDOWS
    const char* temp_dir = posix::GetEnv("TEMP");
    if (temp_dir == NULL || temp_dir[0] == '\0')
      return "\\temp\\";
    else if (temp_dir[strlen(temp_dir) - 1] == '\\')
      return temp_dir;
    else
      return std::string(temp_dir) + "\\";
  #elif GTEST_OS_LINUX_ANDROID
    return "/sdcard/";
  #else
    return "/tmp/";
  #endif  // GTEST_OS_WINDOWS_MOBILE
  }
  
  size_t GetFileSize(FILE* file) {
    fseek(file, 0, SEEK_END);
    return static_cast<size_t>(ftell(file));
  }
  
  std::string ReadEntireFile(FILE* file) {
    const size_t file_size = GetFileSize(file);
    char* const buffer = new char[file_size];
  
    size_t bytes_last_read = 0;  // # of bytes read in the last fread()
    size_t bytes_read = 0;       // # of bytes read so far
  
    fseek(file, 0, SEEK_SET);
  
    // Keeps reading the file until we cannot read further or the
    // pre-determined file size is reached.
    do {
      bytes_last_read = fread(buffer+bytes_read, 1, file_size-bytes_read, file);
      bytes_read += bytes_last_read;
    } while (bytes_last_read > 0 && bytes_read < file_size);
  
    const std::string content(buffer, bytes_read);
    delete[] buffer;
  
    return content;
  }
  
  #if GTEST_HAS_DEATH_TEST
  
  static const ::std::vector<testing::internal::string>* g_injected_test_argvs =
                                          NULL;  // Owned.
  
  void SetInjectableArgvs(const ::std::vector<testing::internal::string>* argvs) {
    if (g_injected_test_argvs != argvs)
      delete g_injected_test_argvs;
    g_injected_test_argvs = argvs;
  }
  
  const ::std::vector<testing::internal::string>& GetInjectableArgvs() {
    if (g_injected_test_argvs != NULL) {
      return *g_injected_test_argvs;
    }
    return GetArgvs();
  }
  #endif  // GTEST_HAS_DEATH_TEST
  
  #if GTEST_OS_WINDOWS_MOBILE
  namespace posix {
  void Abort() {
    DebugBreak();
    TerminateProcess(GetCurrentProcess(), 1);
  }
  }  // namespace posix
  #endif  // GTEST_OS_WINDOWS_MOBILE
  
  // Returns the name of the environment variable corresponding to the
  // given flag.  For example, FlagToEnvVar("foo") will return
  // "GTEST_FOO" in the open-source version.
  static std::string FlagToEnvVar(const char* flag) {
    const std::string full_flag =
        (Message() << GTEST_FLAG_PREFIX_ << flag).GetString();
  
    Message env_var;
    for (size_t i = 0; i != full_flag.length(); i++) {
      env_var << ToUpper(full_flag.c_str()[i]);
    }
  
    return env_var.GetString();
  }
  
  // Parses 'str' for a 32-bit signed integer.  If successful, writes
  // the result to *value and returns true; otherwise leaves *value
  // unchanged and returns false.
  bool ParseInt32(const Message& src_text, const char* str, Int32* value) {
    // Parses the environment variable as a decimal integer.
    char* end = NULL;
    const long long_value = strtol(str, &end, 10);  // NOLINT
  
    // Has strtol() consumed all characters in the string?
    if (*end != '\0') {
      // No - an invalid character was encountered.
      Message msg;
      msg << "WARNING: " << src_text
          << " is expected to be a 32-bit integer, but actually"
          << " has value \"" << str << "\".\n";
      printf("%s", msg.GetString().c_str());
      fflush(stdout);
      return false;
    }
  
    // Is the parsed value in the range of an Int32?
    const Int32 result = static_cast<Int32>(long_value);
    if (long_value == LONG_MAX || long_value == LONG_MIN ||
        // The parsed value overflows as a long.  (strtol() returns
        // LONG_MAX or LONG_MIN when the input overflows.)
        result != long_value
        // The parsed value overflows as an Int32.
        ) {
      Message msg;
      msg << "WARNING: " << src_text
          << " is expected to be a 32-bit integer, but actually"
          << " has value " << str << ", which overflows.\n";
      printf("%s", msg.GetString().c_str());
      fflush(stdout);
      return false;
    }
  
    *value = result;
    return true;
  }
  
  // Reads and returns the Boolean environment variable corresponding to
  // the given flag; if it's not set, returns default_value.
  //
  // The value is considered true iff it's not "0".
  bool BoolFromGTestEnv(const char* flag, bool default_value) {
  #if defined(GTEST_GET_BOOL_FROM_ENV_)
    return GTEST_GET_BOOL_FROM_ENV_(flag, default_value);
  #endif  // defined(GTEST_GET_BOOL_FROM_ENV_)
    const std::string env_var = FlagToEnvVar(flag);
    const char* const string_value = posix::GetEnv(env_var.c_str());
    return string_value == NULL ?
        default_value : strcmp(string_value, "0") != 0;
  }
  
  // Reads and returns a 32-bit integer stored in the environment
  // variable corresponding to the given flag; if it isn't set or
  // doesn't represent a valid 32-bit integer, returns default_value.
  Int32 Int32FromGTestEnv(const char* flag, Int32 default_value) {
  #if defined(GTEST_GET_INT32_FROM_ENV_)
    return GTEST_GET_INT32_FROM_ENV_(flag, default_value);
  #endif  // defined(GTEST_GET_INT32_FROM_ENV_)
    const std::string env_var = FlagToEnvVar(flag);
    const char* const string_value = posix::GetEnv(env_var.c_str());
    if (string_value == NULL) {
      // The environment variable is not set.
      return default_value;
    }
  
    Int32 result = default_value;
    if (!ParseInt32(Message() << "Environment variable " << env_var,
                    string_value, &result)) {
      printf("The default value %s is used.\n",
             (Message() << default_value).GetString().c_str());
      fflush(stdout);
      return default_value;
    }
  
    return result;
  }
  
  // Reads and returns the string environment variable corresponding to
  // the given flag; if it's not set, returns default_value.
  const char* StringFromGTestEnv(const char* flag, const char* default_value) {
  #if defined(GTEST_GET_STRING_FROM_ENV_)
    return GTEST_GET_STRING_FROM_ENV_(flag, default_value);
  #endif  // defined(GTEST_GET_STRING_FROM_ENV_)
    const std::string env_var = FlagToEnvVar(flag);
    const char* const value = posix::GetEnv(env_var.c_str());
    return value == NULL ? default_value : value;
  }
  
  }  // namespace internal
  }  // namespace testing
  // Copyright 2007, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  
  // Google Test - The Google C++ Testing Framework
  //
  // This file implements a universal value printer that can print a
  // value of any type T:
  //
  //   void ::testing::internal::UniversalPrinter<T>::Print(value, ostream_ptr);
  //
  // It uses the << operator when possible, and prints the bytes in the
  // object otherwise.  A user can override its behavior for a class
  // type Foo by defining either operator<<(::std::ostream&, const Foo&)
  // or void PrintTo(const Foo&, ::std::ostream*) in the namespace that
  // defines Foo.
  
  #include <ctype.h>
  #include <stdio.h>
  #include <cwchar>
  #include <ostream>  // NOLINT
  #include <string>
  
  namespace testing {
  
  namespace {
  
  using ::std::ostream;
  
  // Prints a segment of bytes in the given object.
  GTEST_ATTRIBUTE_NO_SANITIZE_MEMORY_
  GTEST_ATTRIBUTE_NO_SANITIZE_ADDRESS_
  GTEST_ATTRIBUTE_NO_SANITIZE_THREAD_
  void PrintByteSegmentInObjectTo(const unsigned char* obj_bytes, size_t start,
                                  size_t count, ostream* os) {
    char text[5] = "";
    for (size_t i = 0; i != count; i++) {
      const size_t j = start + i;
      if (i != 0) {
        // Organizes the bytes into groups of 2 for easy parsing by
        // human.
        if ((j % 2) == 0)
          *os << ' ';
        else
          *os << '-';
      }
      GTEST_SNPRINTF_(text, sizeof(text), "%02X", obj_bytes[j]);
      *os << text;
    }
  }
  
  // Prints the bytes in the given value to the given ostream.
  void PrintBytesInObjectToImpl(const unsigned char* obj_bytes, size_t count,
                                ostream* os) {
    // Tells the user how big the object is.
    *os << count << "-byte object <";
  
    const size_t kThreshold = 132;
    const size_t kChunkSize = 64;
    // If the object size is bigger than kThreshold, we'll have to omit
    // some details by printing only the first and the last kChunkSize
    // bytes.
    // TODO(wan): let the user control the threshold using a flag.
    if (count < kThreshold) {
      PrintByteSegmentInObjectTo(obj_bytes, 0, count, os);
    } else {
      PrintByteSegmentInObjectTo(obj_bytes, 0, kChunkSize, os);
      *os << " ... ";
      // Rounds up to 2-byte boundary.
      const size_t resume_pos = (count - kChunkSize + 1)/2*2;
      PrintByteSegmentInObjectTo(obj_bytes, resume_pos, count - resume_pos, os);
    }
    *os << ">";
  }
  
  }  // namespace
  
  namespace internal2 {
  
  // Delegates to PrintBytesInObjectToImpl() to print the bytes in the
  // given object.  The delegation simplifies the implementation, which
  // uses the << operator and thus is easier done outside of the
  // ::testing::internal namespace, which contains a << operator that
  // sometimes conflicts with the one in STL.
  void PrintBytesInObjectTo(const unsigned char* obj_bytes, size_t count,
                            ostream* os) {
    PrintBytesInObjectToImpl(obj_bytes, count, os);
  }
  
  }  // namespace internal2
  
  namespace internal {
  
  // Depending on the value of a char (or wchar_t), we print it in one
  // of three formats:
  //   - as is if it's a printable ASCII (e.g. 'a', '2', ' '),
  //   - as a hexidecimal escape sequence (e.g. '\x7F'), or
  //   - as a special escape sequence (e.g. '\r', '\n').
  enum CharFormat {
    kAsIs,
    kHexEscape,
    kSpecialEscape
  };
  
  // Returns true if c is a printable ASCII character.  We test the
  // value of c directly instead of calling isprint(), which is buggy on
  // Windows Mobile.
  inline bool IsPrintableAscii(wchar_t c) {
    return 0x20 <= c && c <= 0x7E;
  }
  
  // Prints a wide or narrow char c as a character literal without the
  // quotes, escaping it when necessary; returns how c was formatted.
  // The template argument UnsignedChar is the unsigned version of Char,
  // which is the type of c.
  template <typename UnsignedChar, typename Char>
  static CharFormat PrintAsCharLiteralTo(Char c, ostream* os) {
    switch (static_cast<wchar_t>(c)) {
      case L'\0':
        *os << "\\0";
        break;
      case L'\'':
        *os << "\\'";
        break;
      case L'\\':
        *os << "\\\\";
        break;
      case L'\a':
        *os << "\\a";
        break;
      case L'\b':
        *os << "\\b";
        break;
      case L'\f':
        *os << "\\f";
        break;
      case L'\n':
        *os << "\\n";
        break;
      case L'\r':
        *os << "\\r";
        break;
      case L'\t':
        *os << "\\t";
        break;
      case L'\v':
        *os << "\\v";
        break;
      default:
        if (IsPrintableAscii(c)) {
          *os << static_cast<char>(c);
          return kAsIs;
        } else {
          *os << "\\x" + String::FormatHexInt(static_cast<UnsignedChar>(c));
          return kHexEscape;
        }
    }
    return kSpecialEscape;
  }
  
  // Prints a wchar_t c as if it's part of a string literal, escaping it when
  // necessary; returns how c was formatted.
  static CharFormat PrintAsStringLiteralTo(wchar_t c, ostream* os) {
    switch (c) {
      case L'\'':
        *os << "'";
        return kAsIs;
      case L'"':
        *os << "\\\"";
        return kSpecialEscape;
      default:
        return PrintAsCharLiteralTo<wchar_t>(c, os);
    }
  }
  
  // Prints a char c as if it's part of a string literal, escaping it when
  // necessary; returns how c was formatted.
  static CharFormat PrintAsStringLiteralTo(char c, ostream* os) {
    return PrintAsStringLiteralTo(
        static_cast<wchar_t>(static_cast<unsigned char>(c)), os);
  }
  
  // Prints a wide or narrow character c and its code.  '\0' is printed
  // as "'\\0'", other unprintable characters are also properly escaped
  // using the standard C++ escape sequence.  The template argument
  // UnsignedChar is the unsigned version of Char, which is the type of c.
  template <typename UnsignedChar, typename Char>
  void PrintCharAndCodeTo(Char c, ostream* os) {
    // First, print c as a literal in the most readable form we can find.
    *os << ((sizeof(c) > 1) ? "L'" : "'");
    const CharFormat format = PrintAsCharLiteralTo<UnsignedChar>(c, os);
    *os << "'";
  
    // To aid user debugging, we also print c's code in decimal, unless
    // it's 0 (in which case c was printed as '\\0', making the code
    // obvious).
    if (c == 0)
      return;
    *os << " (" << static_cast<int>(c);
  
    // For more convenience, we print c's code again in hexidecimal,
    // unless c was already printed in the form '\x##' or the code is in
    // [1, 9].
    if (format == kHexEscape || (1 <= c && c <= 9)) {
      // Do nothing.
    } else {
      *os << ", 0x" << String::FormatHexInt(static_cast<UnsignedChar>(c));
    }
    *os << ")";
  }
  
  void PrintTo(unsigned char c, ::std::ostream* os) {
    PrintCharAndCodeTo<unsigned char>(c, os);
  }
  void PrintTo(signed char c, ::std::ostream* os) {
    PrintCharAndCodeTo<unsigned char>(c, os);
  }
  
  // Prints a wchar_t as a symbol if it is printable or as its internal
  // code otherwise and also as its code.  L'\0' is printed as "L'\\0'".
  void PrintTo(wchar_t wc, ostream* os) {
    PrintCharAndCodeTo<wchar_t>(wc, os);
  }
  
  // Prints the given array of characters to the ostream.  CharType must be either
  // char or wchar_t.
  // The array starts at begin, the length is len, it may include '\0' characters
  // and may not be NUL-terminated.
  template <typename CharType>
  GTEST_ATTRIBUTE_NO_SANITIZE_MEMORY_
  GTEST_ATTRIBUTE_NO_SANITIZE_ADDRESS_
  GTEST_ATTRIBUTE_NO_SANITIZE_THREAD_
  static void PrintCharsAsStringTo(
      const CharType* begin, size_t len, ostream* os) {
    const char* const kQuoteBegin = sizeof(CharType) == 1 ? "\"" : "L\"";
    *os << kQuoteBegin;
    bool is_previous_hex = false;
    for (size_t index = 0; index < len; ++index) {
      const CharType cur = begin[index];
      if (is_previous_hex && IsXDigit(cur)) {
        // Previous character is of '\x..' form and this character can be
        // interpreted as another hexadecimal digit in its number. Break string to
        // disambiguate.
        *os << "\" " << kQuoteBegin;
      }
      is_previous_hex = PrintAsStringLiteralTo(cur, os) == kHexEscape;
    }
    *os << "\"";
  }
  
  // Prints a (const) char/wchar_t array of 'len' elements, starting at address
  // 'begin'.  CharType must be either char or wchar_t.
  template <typename CharType>
  GTEST_ATTRIBUTE_NO_SANITIZE_MEMORY_
  GTEST_ATTRIBUTE_NO_SANITIZE_ADDRESS_
  GTEST_ATTRIBUTE_NO_SANITIZE_THREAD_
  static void UniversalPrintCharArray(
      const CharType* begin, size_t len, ostream* os) {
    // The code
    //   const char kFoo[] = "foo";
    // generates an array of 4, not 3, elements, with the last one being '\0'.
    //
    // Therefore when printing a char array, we don't print the last element if
    // it's '\0', such that the output matches the string literal as it's
    // written in the source code.
    if (len > 0 && begin[len - 1] == '\0') {
      PrintCharsAsStringTo(begin, len - 1, os);
      return;
    }
  
    // If, however, the last element in the array is not '\0', e.g.
    //    const char kFoo[] = { 'f', 'o', 'o' };
    // we must print the entire array.  We also print a message to indicate
    // that the array is not NUL-terminated.
    PrintCharsAsStringTo(begin, len, os);
    *os << " (no terminating NUL)";
  }
  
  // Prints a (const) char array of 'len' elements, starting at address 'begin'.
  void UniversalPrintArray(const char* begin, size_t len, ostream* os) {
    UniversalPrintCharArray(begin, len, os);
  }
  
  // Prints a (const) wchar_t array of 'len' elements, starting at address
  // 'begin'.
  void UniversalPrintArray(const wchar_t* begin, size_t len, ostream* os) {
    UniversalPrintCharArray(begin, len, os);
  }
  
  // Prints the given C string to the ostream.
  void PrintTo(const char* s, ostream* os) {
    if (s == NULL) {
      *os << "NULL";
    } else {
      *os << ImplicitCast_<const void*>(s) << " pointing to ";
      PrintCharsAsStringTo(s, strlen(s), os);
    }
  }
  
  // MSVC compiler can be configured to define whar_t as a typedef
  // of unsigned short. Defining an overload for const wchar_t* in that case
  // would cause pointers to unsigned shorts be printed as wide strings,
  // possibly accessing more memory than intended and causing invalid
  // memory accesses. MSVC defines _NATIVE_WCHAR_T_DEFINED symbol when
  // wchar_t is implemented as a native type.
  #if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
  // Prints the given wide C string to the ostream.
  void PrintTo(const wchar_t* s, ostream* os) {
    if (s == NULL) {
      *os << "NULL";
    } else {
      *os << ImplicitCast_<const void*>(s) << " pointing to ";
      PrintCharsAsStringTo(s, std::wcslen(s), os);
    }
  }
  #endif  // wchar_t is native
  
  // Prints a ::string object.
  #if GTEST_HAS_GLOBAL_STRING
  void PrintStringTo(const ::string& s, ostream* os) {
    PrintCharsAsStringTo(s.data(), s.size(), os);
  }
  #endif  // GTEST_HAS_GLOBAL_STRING
  
  void PrintStringTo(const ::std::string& s, ostream* os) {
    PrintCharsAsStringTo(s.data(), s.size(), os);
  }
  
  // Prints a ::wstring object.
  #if GTEST_HAS_GLOBAL_WSTRING
  void PrintWideStringTo(const ::wstring& s, ostream* os) {
    PrintCharsAsStringTo(s.data(), s.size(), os);
  }
  #endif  // GTEST_HAS_GLOBAL_WSTRING
  
  #if GTEST_HAS_STD_WSTRING
  void PrintWideStringTo(const ::std::wstring& s, ostream* os) {
    PrintCharsAsStringTo(s.data(), s.size(), os);
  }
  #endif  // GTEST_HAS_STD_WSTRING
  
  }  // namespace internal
  
  }  // namespace testing
  // Copyright 2008, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: mheule@google.com (Markus Heule)
  //
  // The Google C++ Testing Framework (Google Test)
  
  
  // Indicates that this translation unit is part of Google Test's
  // implementation.  It must come before gtest-internal-inl.h is
  // included, or there will be a compiler error.  This trick exists to
  // prevent the accidental inclusion of gtest-internal-inl.h in the
  // user's code.
  #define GTEST_IMPLEMENTATION_ 1
  #undef GTEST_IMPLEMENTATION_
  
  namespace testing {
  
  using internal::GetUnitTestImpl;
  
  // Gets the summary of the failure message by omitting the stack trace
  // in it.
  std::string TestPartResult::ExtractSummary(const char* message) {
    const char* const stack_trace = strstr(message, internal::kStackTraceMarker);
    return stack_trace == NULL ? message :
        std::string(message, stack_trace);
  }
  
  // Prints a TestPartResult object.
  std::ostream& operator<<(std::ostream& os, const TestPartResult& result) {
    return os
        << result.file_name() << ":" << result.line_number() << ": "
        << (result.type() == TestPartResult::kSuccess ? "Success" :
            result.type() == TestPartResult::kFatalFailure ? "Fatal failure" :
            "Non-fatal failure") << ":\n"
        << result.message() << std::endl;
  }
  
  // Appends a TestPartResult to the array.
  void TestPartResultArray::Append(const TestPartResult& result) {
    array_.push_back(result);
  }
  
  // Returns the TestPartResult at the given index (0-based).
  const TestPartResult& TestPartResultArray::GetTestPartResult(int index) const {
    if (index < 0 || index >= size()) {
      printf("\nInvalid index (%d) into TestPartResultArray.\n", index);
      internal::posix::Abort();
    }
  
    return array_[index];
  }
  
  // Returns the number of TestPartResult objects in the array.
  int TestPartResultArray::size() const {
    return static_cast<int>(array_.size());
  }
  
  namespace internal {
  
  HasNewFatalFailureHelper::HasNewFatalFailureHelper()
      : has_new_fatal_failure_(false),
        original_reporter_(GetUnitTestImpl()->
                           GetTestPartResultReporterForCurrentThread()) {
    GetUnitTestImpl()->SetTestPartResultReporterForCurrentThread(this);
  }
  
  HasNewFatalFailureHelper::~HasNewFatalFailureHelper() {
    GetUnitTestImpl()->SetTestPartResultReporterForCurrentThread(
        original_reporter_);
  }
  
  void HasNewFatalFailureHelper::ReportTestPartResult(
      const TestPartResult& result) {
    if (result.fatally_failed())
      has_new_fatal_failure_ = true;
    original_reporter_->ReportTestPartResult(result);
  }
  
  }  // namespace internal
  
  }  // namespace testing
  // Copyright 2008 Google Inc.
  // All Rights Reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  
  
  namespace testing {
  namespace internal {
  
  #if GTEST_HAS_TYPED_TEST_P
  
  // Skips to the first non-space char in str. Returns an empty string if str
  // contains only whitespace characters.
  static const char* SkipSpaces(const char* str) {
    while (IsSpace(*str))
      str++;
    return str;
  }
  
  static std::vector<std::string> SplitIntoTestNames(const char* src) {
    std::vector<std::string> name_vec;
    src = SkipSpaces(src);
    for (; src != NULL; src = SkipComma(src)) {
      name_vec.push_back(StripTrailingSpaces(GetPrefixUntilComma(src)));
    }
    return name_vec;
  }
  
  // Verifies that registered_tests match the test names in
  // registered_tests_; returns registered_tests if successful, or
  // aborts the program otherwise.
  const char* TypedTestCasePState::VerifyRegisteredTestNames(
      const char* file, int line, const char* registered_tests) {
    typedef RegisteredTestsMap::const_iterator RegisteredTestIter;
    registered_ = true;
  
    std::vector<std::string> name_vec = SplitIntoTestNames(registered_tests);
  
    Message errors;
  
    std::set<std::string> tests;
    for (std::vector<std::string>::const_iterator name_it = name_vec.begin();
         name_it != name_vec.end(); ++name_it) {
      const std::string& name = *name_it;
      if (tests.count(name) != 0) {
        errors << "Test " << name << " is listed more than once.\n";
        continue;
      }
  
      bool found = false;
      for (RegisteredTestIter it = registered_tests_.begin();
           it != registered_tests_.end();
           ++it) {
        if (name == it->first) {
          found = true;
          break;
        }
      }
  
      if (found) {
        tests.insert(name);
      } else {
        errors << "No test named " << name
               << " can be found in this test case.\n";
      }
    }
  
    for (RegisteredTestIter it = registered_tests_.begin();
         it != registered_tests_.end();
         ++it) {
      if (tests.count(it->first) == 0) {
        errors << "You forgot to list test " << it->first << ".\n";
      }
    }
  
    const std::string& errors_str = errors.GetString();
    if (errors_str != "") {
      fprintf(stderr, "%s %s", FormatFileLocation(file, line).c_str(),
              errors_str.c_str());
      fflush(stderr);
      posix::Abort();
    }
  
    return registered_tests;
  }
  
  #endif  // GTEST_HAS_TYPED_TEST_P
  
  }  // namespace internal
  }  // namespace testing
  // Copyright 2008, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  //
  // Google C++ Mocking Framework (Google Mock)
  //
  // This file #includes all Google Mock implementation .cc files.  The
  // purpose is to allow a user to build Google Mock by compiling this
  // file alone.
  
  // This line ensures that gmock.h can be compiled on its own, even
  // when it's fused.
  #include "gmock.h"
  
  // The following lines pull in the real gmock *.cc files.
  // Copyright 2007, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  
  // Google Mock - a framework for writing C++ mock classes.
  //
  // This file implements cardinalities.
  
  
  #include <limits.h>
  #include <ostream>  // NOLINT
  #include <sstream>
  #include <string>
  
  namespace testing {
  
  namespace {
  
  // Implements the Between(m, n) cardinality.
  class BetweenCardinalityImpl : public CardinalityInterface {
   public:
    BetweenCardinalityImpl(int min, int max)
        : min_(min >= 0 ? min : 0),
          max_(max >= min_ ? max : min_) {
      std::stringstream ss;
      if (min < 0) {
        ss << "The invocation lower bound must be >= 0, "
           << "but is actually " << min << ".";
        internal::Expect(false, __FILE__, __LINE__, ss.str());
      } else if (max < 0) {
        ss << "The invocation upper bound must be >= 0, "
           << "but is actually " << max << ".";
        internal::Expect(false, __FILE__, __LINE__, ss.str());
      } else if (min > max) {
        ss << "The invocation upper bound (" << max
           << ") must be >= the invocation lower bound (" << min
           << ").";
        internal::Expect(false, __FILE__, __LINE__, ss.str());
      }
    }
  
    // Conservative estimate on the lower/upper bound of the number of
    // calls allowed.
    virtual int ConservativeLowerBound() const { return min_; }
    virtual int ConservativeUpperBound() const { return max_; }
  
    virtual bool IsSatisfiedByCallCount(int call_count) const {
      return min_ <= call_count && call_count <= max_;
    }
  
    virtual bool IsSaturatedByCallCount(int call_count) const {
      return call_count >= max_;
    }
  
    virtual void DescribeTo(::std::ostream* os) const;
  
   private:
    const int min_;
    const int max_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(BetweenCardinalityImpl);
  };
  
  // Formats "n times" in a human-friendly way.
  inline internal::string FormatTimes(int n) {
    if (n == 1) {
      return "once";
    } else if (n == 2) {
      return "twice";
    } else {
      std::stringstream ss;
      ss << n << " times";
      return ss.str();
    }
  }
  
  // Describes the Between(m, n) cardinality in human-friendly text.
  void BetweenCardinalityImpl::DescribeTo(::std::ostream* os) const {
    if (min_ == 0) {
      if (max_ == 0) {
        *os << "never called";
      } else if (max_ == INT_MAX) {
        *os << "called any number of times";
      } else {
        *os << "called at most " << FormatTimes(max_);
      }
    } else if (min_ == max_) {
      *os << "called " << FormatTimes(min_);
    } else if (max_ == INT_MAX) {
      *os << "called at least " << FormatTimes(min_);
    } else {
      // 0 < min_ < max_ < INT_MAX
      *os << "called between " << min_ << " and " << max_ << " times";
    }
  }
  
  }  // Unnamed namespace
  
  // Describes the given call count to an ostream.
  void Cardinality::DescribeActualCallCountTo(int actual_call_count,
                                              ::std::ostream* os) {
    if (actual_call_count > 0) {
      *os << "called " << FormatTimes(actual_call_count);
    } else {
      *os << "never called";
    }
  }
  
  // Creates a cardinality that allows at least n calls.
  GTEST_API_ Cardinality AtLeast(int n) { return Between(n, INT_MAX); }
  
  // Creates a cardinality that allows at most n calls.
  GTEST_API_ Cardinality AtMost(int n) { return Between(0, n); }
  
  // Creates a cardinality that allows any number of calls.
  GTEST_API_ Cardinality AnyNumber() { return AtLeast(0); }
  
  // Creates a cardinality that allows between min and max calls.
  GTEST_API_ Cardinality Between(int min, int max) {
    return Cardinality(new BetweenCardinalityImpl(min, max));
  }
  
  // Creates a cardinality that allows exactly n calls.
  GTEST_API_ Cardinality Exactly(int n) { return Between(n, n); }
  
  }  // namespace testing
  // Copyright 2007, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  
  // Google Mock - a framework for writing C++ mock classes.
  //
  // This file defines some utilities useful for implementing Google
  // Mock.  They are subject to change without notice, so please DO NOT
  // USE THEM IN USER CODE.
  
  
  #include <ctype.h>
  #include <ostream>  // NOLINT
  #include <string>
  
  namespace testing {
  namespace internal {
  
  // Converts an identifier name to a space-separated list of lower-case
  // words.  Each maximum substring of the form [A-Za-z][a-z]*|\d+ is
  // treated as one word.  For example, both "FooBar123" and
  // "foo_bar_123" are converted to "foo bar 123".
  GTEST_API_ string ConvertIdentifierNameToWords(const char* id_name) {
    string result;
    char prev_char = '\0';
    for (const char* p = id_name; *p != '\0'; prev_char = *(p++)) {
      // We don't care about the current locale as the input is
      // guaranteed to be a valid C++ identifier name.
      const bool starts_new_word = IsUpper(*p) ||
          (!IsAlpha(prev_char) && IsLower(*p)) ||
          (!IsDigit(prev_char) && IsDigit(*p));
  
      if (IsAlNum(*p)) {
        if (starts_new_word && result != "")
          result += ' ';
        result += ToLower(*p);
      }
    }
    return result;
  }
  
  // This class reports Google Mock failures as Google Test failures.  A
  // user can define another class in a similar fashion if he intends to
  // use Google Mock with a testing framework other than Google Test.
  class GoogleTestFailureReporter : public FailureReporterInterface {
   public:
    virtual void ReportFailure(FailureType type, const char* file, int line,
                               const string& message) {
      AssertHelper(type == kFatal ?
                   TestPartResult::kFatalFailure :
                   TestPartResult::kNonFatalFailure,
                   file,
                   line,
                   message.c_str()) = Message();
      if (type == kFatal) {
        posix::Abort();
      }
    }
  };
  
  // Returns the global failure reporter.  Will create a
  // GoogleTestFailureReporter and return it the first time called.
  GTEST_API_ FailureReporterInterface* GetFailureReporter() {
    // Points to the global failure reporter used by Google Mock.  gcc
    // guarantees that the following use of failure_reporter is
    // thread-safe.  We may need to add additional synchronization to
    // protect failure_reporter if we port Google Mock to other
    // compilers.
    static FailureReporterInterface* const failure_reporter =
        new GoogleTestFailureReporter();
    return failure_reporter;
  }
  
  // Protects global resources (stdout in particular) used by Log().
  static GTEST_DEFINE_STATIC_MUTEX_(g_log_mutex);
  
  // Returns true iff a log with the given severity is visible according
  // to the --gmock_verbose flag.
  GTEST_API_ bool LogIsVisible(LogSeverity severity) {
    if (GMOCK_FLAG(verbose) == kInfoVerbosity) {
      // Always show the log if --gmock_verbose=info.
      return true;
    } else if (GMOCK_FLAG(verbose) == kErrorVerbosity) {
      // Always hide it if --gmock_verbose=error.
      return false;
    } else {
      // If --gmock_verbose is neither "info" nor "error", we treat it
      // as "warning" (its default value).
      return severity == kWarning;
    }
  }
  
  // Prints the given message to stdout iff 'severity' >= the level
  // specified by the --gmock_verbose flag.  If stack_frames_to_skip >=
  // 0, also prints the stack trace excluding the top
  // stack_frames_to_skip frames.  In opt mode, any positive
  // stack_frames_to_skip is treated as 0, since we don't know which
  // function calls will be inlined by the compiler and need to be
  // conservative.
  GTEST_API_ void Log(LogSeverity severity,
                      const string& message,
                      int stack_frames_to_skip) {
    if (!LogIsVisible(severity))
      return;
  
    // Ensures that logs from different threads don't interleave.
    MutexLock l(&g_log_mutex);
  
    // "using ::std::cout;" doesn't work with Symbian's STLport, where cout is a
    // macro.
  
    if (severity == kWarning) {
      // Prints a GMOCK WARNING marker to make the warnings easily searchable.
      std::cout << "\nGMOCK WARNING:";
    }
    // Pre-pends a new-line to message if it doesn't start with one.
    if (message.empty() || message[0] != '\n') {
      std::cout << "\n";
    }
    std::cout << message;
    if (stack_frames_to_skip >= 0) {
  #ifdef NDEBUG
      // In opt mode, we have to be conservative and skip no stack frame.
      const int actual_to_skip = 0;
  #else
      // In dbg mode, we can do what the caller tell us to do (plus one
      // for skipping this function's stack frame).
      const int actual_to_skip = stack_frames_to_skip + 1;
  #endif  // NDEBUG
  
      // Appends a new-line to message if it doesn't end with one.
      if (!message.empty() && *message.rbegin() != '\n') {
        std::cout << "\n";
      }
      std::cout << "Stack trace:\n"
           << ::testing::internal::GetCurrentOsStackTraceExceptTop(
               ::testing::UnitTest::GetInstance(), actual_to_skip);
    }
    std::cout << ::std::flush;
  }
  
  }  // namespace internal
  }  // namespace testing
  // Copyright 2007, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  
  // Google Mock - a framework for writing C++ mock classes.
  //
  // This file implements Matcher<const string&>, Matcher<string>, and
  // utilities for defining matchers.
  
  
  #include <string.h>
  #include <sstream>
  #include <string>
  
  namespace testing {
  
  // Constructs a matcher that matches a const string& whose value is
  // equal to s.
  Matcher<const internal::string&>::Matcher(const internal::string& s) {
    *this = Eq(s);
  }
  
  // Constructs a matcher that matches a const string& whose value is
  // equal to s.
  Matcher<const internal::string&>::Matcher(const char* s) {
    *this = Eq(internal::string(s));
  }
  
  // Constructs a matcher that matches a string whose value is equal to s.
  Matcher<internal::string>::Matcher(const internal::string& s) { *this = Eq(s); }
  
  // Constructs a matcher that matches a string whose value is equal to s.
  Matcher<internal::string>::Matcher(const char* s) {
    *this = Eq(internal::string(s));
  }
  
  #if GTEST_HAS_STRING_PIECE_
  // Constructs a matcher that matches a const StringPiece& whose value is
  // equal to s.
  Matcher<const StringPiece&>::Matcher(const internal::string& s) {
    *this = Eq(s);
  }
  
  // Constructs a matcher that matches a const StringPiece& whose value is
  // equal to s.
  Matcher<const StringPiece&>::Matcher(const char* s) {
    *this = Eq(internal::string(s));
  }
  
  // Constructs a matcher that matches a const StringPiece& whose value is
  // equal to s.
  Matcher<const StringPiece&>::Matcher(StringPiece s) {
    *this = Eq(s.ToString());
  }
  
  // Constructs a matcher that matches a StringPiece whose value is equal to s.
  Matcher<StringPiece>::Matcher(const internal::string& s) {
    *this = Eq(s);
  }
  
  // Constructs a matcher that matches a StringPiece whose value is equal to s.
  Matcher<StringPiece>::Matcher(const char* s) {
    *this = Eq(internal::string(s));
  }
  
  // Constructs a matcher that matches a StringPiece whose value is equal to s.
  Matcher<StringPiece>::Matcher(StringPiece s) {
    *this = Eq(s.ToString());
  }
  #endif  // GTEST_HAS_STRING_PIECE_
  
  namespace internal {
  
  // Joins a vector of strings as if they are fields of a tuple; returns
  // the joined string.
  GTEST_API_ string JoinAsTuple(const Strings& fields) {
    switch (fields.size()) {
      case 0:
        return "";
      case 1:
        return fields[0];
      default:
        string result = "(" + fields[0];
        for (size_t i = 1; i < fields.size(); i++) {
          result += ", ";
          result += fields[i];
        }
        result += ")";
        return result;
    }
  }
  
  // Returns the description for a matcher defined using the MATCHER*()
  // macro where the user-supplied description string is "", if
  // 'negation' is false; otherwise returns the description of the
  // negation of the matcher.  'param_values' contains a list of strings
  // that are the print-out of the matcher's parameters.
  GTEST_API_ string FormatMatcherDescription(bool negation,
                                             const char* matcher_name,
                                             const Strings& param_values) {
    string result = ConvertIdentifierNameToWords(matcher_name);
    if (param_values.size() >= 1)
      result += " " + JoinAsTuple(param_values);
    return negation ? "not (" + result + ")" : result;
  }
  
  // FindMaxBipartiteMatching and its helper class.
  //
  // Uses the well-known Ford-Fulkerson max flow method to find a maximum
  // bipartite matching. Flow is considered to be from left to right.
  // There is an implicit source node that is connected to all of the left
  // nodes, and an implicit sink node that is connected to all of the
  // right nodes. All edges have unit capacity.
  //
  // Neither the flow graph nor the residual flow graph are represented
  // explicitly. Instead, they are implied by the information in 'graph' and
  // a vector<int> called 'left_' whose elements are initialized to the
  // value kUnused. This represents the initial state of the algorithm,
  // where the flow graph is empty, and the residual flow graph has the
  // following edges:
  //   - An edge from source to each left_ node
  //   - An edge from each right_ node to sink
  //   - An edge from each left_ node to each right_ node, if the
  //     corresponding edge exists in 'graph'.
  //
  // When the TryAugment() method adds a flow, it sets left_[l] = r for some
  // nodes l and r. This induces the following changes:
  //   - The edges (source, l), (l, r), and (r, sink) are added to the
  //     flow graph.
  //   - The same three edges are removed from the residual flow graph.
  //   - The reverse edges (l, source), (r, l), and (sink, r) are added
  //     to the residual flow graph, which is a directional graph
  //     representing unused flow capacity.
  //
  // When the method augments a flow (moving left_[l] from some r1 to some
  // other r2), this can be thought of as "undoing" the above steps with
  // respect to r1 and "redoing" them with respect to r2.
  //
  // It bears repeating that the flow graph and residual flow graph are
  // never represented explicitly, but can be derived by looking at the
  // information in 'graph' and in left_.
  //
  // As an optimization, there is a second vector<int> called right_ which
  // does not provide any new information. Instead, it enables more
  // efficient queries about edges entering or leaving the right-side nodes
  // of the flow or residual flow graphs. The following invariants are
  // maintained:
  //
  // left[l] == kUnused or right[left[l]] == l
  // right[r] == kUnused or left[right[r]] == r
  //
  // . [ source ]                                        .
  // .   |||                                             .
  // .   |||                                             .
  // .   ||\--> left[0]=1  ---\    right[0]=-1 ----\     .
  // .   ||                   |                    |     .
  // .   |\---> left[1]=-1    \--> right[1]=0  ---\|     .
  // .   |                                        ||     .
  // .   \----> left[2]=2  ------> right[2]=2  --\||     .
  // .                                           |||     .
  // .         elements           matchers       vvv     .
  // .                                         [ sink ]  .
  //
  // See Also:
  //   [1] Cormen, et al (2001). "Section 26.2: The Ford-Fulkerson method".
  //       "Introduction to Algorithms (Second ed.)", pp. 651-664.
  //   [2] "Ford-Fulkerson algorithm", Wikipedia,
  //       'http://en.wikipedia.org/wiki/Ford%E2%80%93Fulkerson_algorithm'
  class MaxBipartiteMatchState {
   public:
    explicit MaxBipartiteMatchState(const MatchMatrix& graph)
        : graph_(&graph),
          left_(graph_->LhsSize(), kUnused),
          right_(graph_->RhsSize(), kUnused) {
    }
  
    // Returns the edges of a maximal match, each in the form {left, right}.
    ElementMatcherPairs Compute() {
      // 'seen' is used for path finding { 0: unseen, 1: seen }.
      ::std::vector<char> seen;
      // Searches the residual flow graph for a path from each left node to
      // the sink in the residual flow graph, and if one is found, add flow
      // to the graph. It's okay to search through the left nodes once. The
      // edge from the implicit source node to each previously-visited left
      // node will have flow if that left node has any path to the sink
      // whatsoever. Subsequent augmentations can only add flow to the
      // network, and cannot take away that previous flow unit from the source.
      // Since the source-to-left edge can only carry one flow unit (or,
      // each element can be matched to only one matcher), there is no need
      // to visit the left nodes more than once looking for augmented paths.
      // The flow is known to be possible or impossible by looking at the
      // node once.
      for (size_t ilhs = 0; ilhs < graph_->LhsSize(); ++ilhs) {
        // Reset the path-marking vector and try to find a path from
        // source to sink starting at the left_[ilhs] node.
        GTEST_CHECK_(left_[ilhs] == kUnused)
            << "ilhs: " << ilhs << ", left_[ilhs]: " << left_[ilhs];
        // 'seen' initialized to 'graph_->RhsSize()' copies of 0.
        seen.assign(graph_->RhsSize(), 0);
        TryAugment(ilhs, &seen);
      }
      ElementMatcherPairs result;
      for (size_t ilhs = 0; ilhs < left_.size(); ++ilhs) {
        size_t irhs = left_[ilhs];
        if (irhs == kUnused) continue;
        result.push_back(ElementMatcherPair(ilhs, irhs));
      }
      return result;
    }
  
   private:
    static const size_t kUnused = static_cast<size_t>(-1);
  
    // Perform a depth-first search from left node ilhs to the sink.  If a
    // path is found, flow is added to the network by linking the left and
    // right vector elements corresponding each segment of the path.
    // Returns true if a path to sink was found, which means that a unit of
    // flow was added to the network. The 'seen' vector elements correspond
    // to right nodes and are marked to eliminate cycles from the search.
    //
    // Left nodes will only be explored at most once because they
    // are accessible from at most one right node in the residual flow
    // graph.
    //
    // Note that left_[ilhs] is the only element of left_ that TryAugment will
    // potentially transition from kUnused to another value. Any other
    // left_ element holding kUnused before TryAugment will be holding it
    // when TryAugment returns.
    //
    bool TryAugment(size_t ilhs, ::std::vector<char>* seen) {
      for (size_t irhs = 0; irhs < graph_->RhsSize(); ++irhs) {
        if ((*seen)[irhs])
          continue;
        if (!graph_->HasEdge(ilhs, irhs))
          continue;
        // There's an available edge from ilhs to irhs.
        (*seen)[irhs] = 1;
        // Next a search is performed to determine whether
        // this edge is a dead end or leads to the sink.
        //
        // right_[irhs] == kUnused means that there is residual flow from
        // right node irhs to the sink, so we can use that to finish this
        // flow path and return success.
        //
        // Otherwise there is residual flow to some ilhs. We push flow
        // along that path and call ourselves recursively to see if this
        // ultimately leads to sink.
        if (right_[irhs] == kUnused || TryAugment(right_[irhs], seen)) {
          // Add flow from left_[ilhs] to right_[irhs].
          left_[ilhs] = irhs;
          right_[irhs] = ilhs;
          return true;
        }
      }
      return false;
    }
  
    const MatchMatrix* graph_;  // not owned
    // Each element of the left_ vector represents a left hand side node
    // (i.e. an element) and each element of right_ is a right hand side
    // node (i.e. a matcher). The values in the left_ vector indicate
    // outflow from that node to a node on the the right_ side. The values
    // in the right_ indicate inflow, and specify which left_ node is
    // feeding that right_ node, if any. For example, left_[3] == 1 means
    // there's a flow from element #3 to matcher #1. Such a flow would also
    // be redundantly represented in the right_ vector as right_[1] == 3.
    // Elements of left_ and right_ are either kUnused or mutually
    // referent. Mutually referent means that left_[right_[i]] = i and
    // right_[left_[i]] = i.
    ::std::vector<size_t> left_;
    ::std::vector<size_t> right_;
  
    GTEST_DISALLOW_ASSIGN_(MaxBipartiteMatchState);
  };
  
  const size_t MaxBipartiteMatchState::kUnused;
  
  GTEST_API_ ElementMatcherPairs
  FindMaxBipartiteMatching(const MatchMatrix& g) {
    return MaxBipartiteMatchState(g).Compute();
  }
  
  static void LogElementMatcherPairVec(const ElementMatcherPairs& pairs,
                                       ::std::ostream* stream) {
    typedef ElementMatcherPairs::const_iterator Iter;
    ::std::ostream& os = *stream;
    os << "{";
    const char *sep = "";
    for (Iter it = pairs.begin(); it != pairs.end(); ++it) {
      os << sep << "\n  ("
         << "element #" << it->first << ", "
         << "matcher #" << it->second << ")";
      sep = ",";
    }
    os << "\n}";
  }
  
  // Tries to find a pairing, and explains the result.
  GTEST_API_ bool FindPairing(const MatchMatrix& matrix,
                              MatchResultListener* listener) {
    ElementMatcherPairs matches = FindMaxBipartiteMatching(matrix);
  
    size_t max_flow = matches.size();
    bool result = (max_flow == matrix.RhsSize());
  
    if (!result) {
      if (listener->IsInterested()) {
        *listener << "where no permutation of the elements can "
                     "satisfy all matchers, and the closest match is "
                  << max_flow << " of " << matrix.RhsSize()
                  << " matchers with the pairings:\n";
        LogElementMatcherPairVec(matches, listener->stream());
      }
      return false;
    }
  
    if (matches.size() > 1) {
      if (listener->IsInterested()) {
        const char *sep = "where:\n";
        for (size_t mi = 0; mi < matches.size(); ++mi) {
          *listener << sep << " - element #" << matches[mi].first
                    << " is matched by matcher #" << matches[mi].second;
          sep = ",\n";
        }
      }
    }
    return true;
  }
  
  bool MatchMatrix::NextGraph() {
    for (size_t ilhs = 0; ilhs < LhsSize(); ++ilhs) {
      for (size_t irhs = 0; irhs < RhsSize(); ++irhs) {
        char& b = matched_[SpaceIndex(ilhs, irhs)];
        if (!b) {
          b = 1;
          return true;
        }
        b = 0;
      }
    }
    return false;
  }
  
  void MatchMatrix::Randomize() {
    for (size_t ilhs = 0; ilhs < LhsSize(); ++ilhs) {
      for (size_t irhs = 0; irhs < RhsSize(); ++irhs) {
        char& b = matched_[SpaceIndex(ilhs, irhs)];
        b = static_cast<char>(rand() & 1);  // NOLINT
      }
    }
  }
  
  string MatchMatrix::DebugString() const {
    ::std::stringstream ss;
    const char *sep = "";
    for (size_t i = 0; i < LhsSize(); ++i) {
      ss << sep;
      for (size_t j = 0; j < RhsSize(); ++j) {
        ss << HasEdge(i, j);
      }
      sep = ";";
    }
    return ss.str();
  }
  
  void UnorderedElementsAreMatcherImplBase::DescribeToImpl(
      ::std::ostream* os) const {
    if (matcher_describers_.empty()) {
      *os << "is empty";
      return;
    }
    if (matcher_describers_.size() == 1) {
      *os << "has " << Elements(1) << " and that element ";
      matcher_describers_[0]->DescribeTo(os);
      return;
    }
    *os << "has " << Elements(matcher_describers_.size())
        << " and there exists some permutation of elements such that:\n";
    const char* sep = "";
    for (size_t i = 0; i != matcher_describers_.size(); ++i) {
      *os << sep << " - element #" << i << " ";
      matcher_describers_[i]->DescribeTo(os);
      sep = ", and\n";
    }
  }
  
  void UnorderedElementsAreMatcherImplBase::DescribeNegationToImpl(
      ::std::ostream* os) const {
    if (matcher_describers_.empty()) {
      *os << "isn't empty";
      return;
    }
    if (matcher_describers_.size() == 1) {
      *os << "doesn't have " << Elements(1)
          << ", or has " << Elements(1) << " that ";
      matcher_describers_[0]->DescribeNegationTo(os);
      return;
    }
    *os << "doesn't have " << Elements(matcher_describers_.size())
        << ", or there exists no permutation of elements such that:\n";
    const char* sep = "";
    for (size_t i = 0; i != matcher_describers_.size(); ++i) {
      *os << sep << " - element #" << i << " ";
      matcher_describers_[i]->DescribeTo(os);
      sep = ", and\n";
    }
  }
  
  // Checks that all matchers match at least one element, and that all
  // elements match at least one matcher. This enables faster matching
  // and better error reporting.
  // Returns false, writing an explanation to 'listener', if and only
  // if the success criteria are not met.
  bool UnorderedElementsAreMatcherImplBase::
  VerifyAllElementsAndMatchersAreMatched(
      const ::std::vector<string>& element_printouts,
      const MatchMatrix& matrix,
      MatchResultListener* listener) const {
    bool result = true;
    ::std::vector<char> element_matched(matrix.LhsSize(), 0);
    ::std::vector<char> matcher_matched(matrix.RhsSize(), 0);
  
    for (size_t ilhs = 0; ilhs < matrix.LhsSize(); ilhs++) {
      for (size_t irhs = 0; irhs < matrix.RhsSize(); irhs++) {
        char matched = matrix.HasEdge(ilhs, irhs);
        element_matched[ilhs] |= matched;
        matcher_matched[irhs] |= matched;
      }
    }
  
    {
      const char* sep =
          "where the following matchers don't match any elements:\n";
      for (size_t mi = 0; mi < matcher_matched.size(); ++mi) {
        if (matcher_matched[mi])
          continue;
        result = false;
        if (listener->IsInterested()) {
          *listener << sep << "matcher #" << mi << ": ";
          matcher_describers_[mi]->DescribeTo(listener->stream());
          sep = ",\n";
        }
      }
    }
  
    {
      const char* sep =
          "where the following elements don't match any matchers:\n";
      const char* outer_sep = "";
      if (!result) {
        outer_sep = "\nand ";
      }
      for (size_t ei = 0; ei < element_matched.size(); ++ei) {
        if (element_matched[ei])
          continue;
        result = false;
        if (listener->IsInterested()) {
          *listener << outer_sep << sep << "element #" << ei << ": "
                    << element_printouts[ei];
          sep = ",\n";
          outer_sep = "";
        }
      }
    }
    return result;
  }
  
  }  // namespace internal
  }  // namespace testing
  // Copyright 2007, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  
  // Google Mock - a framework for writing C++ mock classes.
  //
  // This file implements the spec builder syntax (ON_CALL and
  // EXPECT_CALL).
  
  
  #include <stdlib.h>
  #include <iostream>  // NOLINT
  #include <map>
  #include <set>
  #include <string>
  
  #if GTEST_OS_CYGWIN || GTEST_OS_LINUX || GTEST_OS_MAC
  # include <unistd.h>  // NOLINT
  #endif
  
  namespace testing {
  namespace internal {
  
  // Protects the mock object registry (in class Mock), all function
  // mockers, and all expectations.
  GTEST_API_ GTEST_DEFINE_STATIC_MUTEX_(g_gmock_mutex);
  
  // Logs a message including file and line number information.
  GTEST_API_ void LogWithLocation(testing::internal::LogSeverity severity,
                                  const char* file, int line,
                                  const string& message) {
    ::std::ostringstream s;
    s << file << ":" << line << ": " << message << ::std::endl;
    Log(severity, s.str(), 0);
  }
  
  // Constructs an ExpectationBase object.
  ExpectationBase::ExpectationBase(const char* a_file,
                                   int a_line,
                                   const string& a_source_text)
      : file_(a_file),
        line_(a_line),
        source_text_(a_source_text),
        cardinality_specified_(false),
        cardinality_(Exactly(1)),
        call_count_(0),
        retired_(false),
        extra_matcher_specified_(false),
        repeated_action_specified_(false),
        retires_on_saturation_(false),
        last_clause_(kNone),
        action_count_checked_(false) {}
  
  // Destructs an ExpectationBase object.
  ExpectationBase::~ExpectationBase() {}
  
  // Explicitly specifies the cardinality of this expectation.  Used by
  // the subclasses to implement the .Times() clause.
  void ExpectationBase::SpecifyCardinality(const Cardinality& a_cardinality) {
    cardinality_specified_ = true;
    cardinality_ = a_cardinality;
  }
  
  // Retires all pre-requisites of this expectation.
  void ExpectationBase::RetireAllPreRequisites()
      GTEST_EXCLUSIVE_LOCK_REQUIRED_(g_gmock_mutex) {
    if (is_retired()) {
      // We can take this short-cut as we never retire an expectation
      // until we have retired all its pre-requisites.
      return;
    }
  
    for (ExpectationSet::const_iterator it = immediate_prerequisites_.begin();
         it != immediate_prerequisites_.end(); ++it) {
      ExpectationBase* const prerequisite = it->expectation_base().get();
      if (!prerequisite->is_retired()) {
        prerequisite->RetireAllPreRequisites();
        prerequisite->Retire();
      }
    }
  }
  
  // Returns true iff all pre-requisites of this expectation have been
  // satisfied.
  bool ExpectationBase::AllPrerequisitesAreSatisfied() const
      GTEST_EXCLUSIVE_LOCK_REQUIRED_(g_gmock_mutex) {
    g_gmock_mutex.AssertHeld();
    for (ExpectationSet::const_iterator it = immediate_prerequisites_.begin();
         it != immediate_prerequisites_.end(); ++it) {
      if (!(it->expectation_base()->IsSatisfied()) ||
          !(it->expectation_base()->AllPrerequisitesAreSatisfied()))
        return false;
    }
    return true;
  }
  
  // Adds unsatisfied pre-requisites of this expectation to 'result'.
  void ExpectationBase::FindUnsatisfiedPrerequisites(ExpectationSet* result) const
      GTEST_EXCLUSIVE_LOCK_REQUIRED_(g_gmock_mutex) {
    g_gmock_mutex.AssertHeld();
    for (ExpectationSet::const_iterator it = immediate_prerequisites_.begin();
         it != immediate_prerequisites_.end(); ++it) {
      if (it->expectation_base()->IsSatisfied()) {
        // If *it is satisfied and has a call count of 0, some of its
        // pre-requisites may not be satisfied yet.
        if (it->expectation_base()->call_count_ == 0) {
          it->expectation_base()->FindUnsatisfiedPrerequisites(result);
        }
      } else {
        // Now that we know *it is unsatisfied, we are not so interested
        // in whether its pre-requisites are satisfied.  Therefore we
        // don't recursively call FindUnsatisfiedPrerequisites() here.
        *result += *it;
      }
    }
  }
  
  // Describes how many times a function call matching this
  // expectation has occurred.
  void ExpectationBase::DescribeCallCountTo(::std::ostream* os) const
      GTEST_EXCLUSIVE_LOCK_REQUIRED_(g_gmock_mutex) {
    g_gmock_mutex.AssertHeld();
  
    // Describes how many times the function is expected to be called.
    *os << "         Expected: to be ";
    cardinality().DescribeTo(os);
    *os << "\n           Actual: ";
    Cardinality::DescribeActualCallCountTo(call_count(), os);
  
    // Describes the state of the expectation (e.g. is it satisfied?
    // is it active?).
    *os << " - " << (IsOverSaturated() ? "over-saturated" :
                     IsSaturated() ? "saturated" :
                     IsSatisfied() ? "satisfied" : "unsatisfied")
        << " and "
        << (is_retired() ? "retired" : "active");
  }
  
  // Checks the action count (i.e. the number of WillOnce() and
  // WillRepeatedly() clauses) against the cardinality if this hasn't
  // been done before.  Prints a warning if there are too many or too
  // few actions.
  void ExpectationBase::CheckActionCountIfNotDone() const
      GTEST_LOCK_EXCLUDED_(mutex_) {
    bool should_check = false;
    {
      MutexLock l(&mutex_);
      if (!action_count_checked_) {
        action_count_checked_ = true;
        should_check = true;
      }
    }
  
    if (should_check) {
      if (!cardinality_specified_) {
        // The cardinality was inferred - no need to check the action
        // count against it.
        return;
      }
  
      // The cardinality was explicitly specified.
      const int action_count = static_cast<int>(untyped_actions_.size());
      const int upper_bound = cardinality().ConservativeUpperBound();
      const int lower_bound = cardinality().ConservativeLowerBound();
      bool too_many;  // True if there are too many actions, or false
      // if there are too few.
      if (action_count > upper_bound ||
          (action_count == upper_bound && repeated_action_specified_)) {
        too_many = true;
      } else if (0 < action_count && action_count < lower_bound &&
                 !repeated_action_specified_) {
        too_many = false;
      } else {
        return;
      }
  
      ::std::stringstream ss;
      DescribeLocationTo(&ss);
      ss << "Too " << (too_many ? "many" : "few")
         << " actions specified in " << source_text() << "...\n"
         << "Expected to be ";
      cardinality().DescribeTo(&ss);
      ss << ", but has " << (too_many ? "" : "only ")
         << action_count << " WillOnce()"
         << (action_count == 1 ? "" : "s");
      if (repeated_action_specified_) {
        ss << " and a WillRepeatedly()";
      }
      ss << ".";
      Log(kWarning, ss.str(), -1);  // -1 means "don't print stack trace".
    }
  }
  
  // Implements the .Times() clause.
  void ExpectationBase::UntypedTimes(const Cardinality& a_cardinality) {
    if (last_clause_ == kTimes) {
      ExpectSpecProperty(false,
                         ".Times() cannot appear "
                         "more than once in an EXPECT_CALL().");
    } else {
      ExpectSpecProperty(last_clause_ < kTimes,
                         ".Times() cannot appear after "
                         ".InSequence(), .WillOnce(), .WillRepeatedly(), "
                         "or .RetiresOnSaturation().");
    }
    last_clause_ = kTimes;
  
    SpecifyCardinality(a_cardinality);
  }
  
  // Points to the implicit sequence introduced by a living InSequence
  // object (if any) in the current thread or NULL.
  GTEST_API_ ThreadLocal<Sequence*> g_gmock_implicit_sequence;
  
  // Reports an uninteresting call (whose description is in msg) in the
  // manner specified by 'reaction'.
  void ReportUninterestingCall(CallReaction reaction, const string& msg) {
    // Include a stack trace only if --gmock_verbose=info is specified.
    const int stack_frames_to_skip =
        GMOCK_FLAG(verbose) == kInfoVerbosity ? 3 : -1;
    switch (reaction) {
      case kAllow:
        Log(kInfo, msg, stack_frames_to_skip);
        break;
      case kWarn:
        Log(kWarning,
            msg +
            "\nNOTE: You can safely ignore the above warning unless this "
            "call should not happen.  Do not suppress it by blindly adding "
            "an EXPECT_CALL() if you don't mean to enforce the call.  "
            "See http://code.google.com/p/googlemock/wiki/CookBook#"
            "Knowing_When_to_Expect for details.\n",
            stack_frames_to_skip);
        break;
      default:  // FAIL
        Expect(false, NULL, -1, msg);
    }
  }
  
  UntypedFunctionMockerBase::UntypedFunctionMockerBase()
      : mock_obj_(NULL), name_("") {}
  
  UntypedFunctionMockerBase::~UntypedFunctionMockerBase() {}
  
  // Sets the mock object this mock method belongs to, and registers
  // this information in the global mock registry.  Will be called
  // whenever an EXPECT_CALL() or ON_CALL() is executed on this mock
  // method.
  void UntypedFunctionMockerBase::RegisterOwner(const void* mock_obj)
      GTEST_LOCK_EXCLUDED_(g_gmock_mutex) {
    {
      MutexLock l(&g_gmock_mutex);
      mock_obj_ = mock_obj;
    }
    Mock::Register(mock_obj, this);
  }
  
  // Sets the mock object this mock method belongs to, and sets the name
  // of the mock function.  Will be called upon each invocation of this
  // mock function.
  void UntypedFunctionMockerBase::SetOwnerAndName(const void* mock_obj,
                                                  const char* name)
      GTEST_LOCK_EXCLUDED_(g_gmock_mutex) {
    // We protect name_ under g_gmock_mutex in case this mock function
    // is called from two threads concurrently.
    MutexLock l(&g_gmock_mutex);
    mock_obj_ = mock_obj;
    name_ = name;
  }
  
  // Returns the name of the function being mocked.  Must be called
  // after RegisterOwner() or SetOwnerAndName() has been called.
  const void* UntypedFunctionMockerBase::MockObject() const
      GTEST_LOCK_EXCLUDED_(g_gmock_mutex) {
    const void* mock_obj;
    {
      // We protect mock_obj_ under g_gmock_mutex in case this mock
      // function is called from two threads concurrently.
      MutexLock l(&g_gmock_mutex);
      Assert(mock_obj_ != NULL, __FILE__, __LINE__,
             "MockObject() must not be called before RegisterOwner() or "
             "SetOwnerAndName() has been called.");
      mock_obj = mock_obj_;
    }
    return mock_obj;
  }
  
  // Returns the name of this mock method.  Must be called after
  // SetOwnerAndName() has been called.
  const char* UntypedFunctionMockerBase::Name() const
      GTEST_LOCK_EXCLUDED_(g_gmock_mutex) {
    const char* name;
    {
      // We protect name_ under g_gmock_mutex in case this mock
      // function is called from two threads concurrently.
      MutexLock l(&g_gmock_mutex);
      Assert(name_ != NULL, __FILE__, __LINE__,
             "Name() must not be called before SetOwnerAndName() has "
             "been called.");
      name = name_;
    }
    return name;
  }
  
  // Calculates the result of invoking this mock function with the given
  // arguments, prints it, and returns it.  The caller is responsible
  // for deleting the result.
  UntypedActionResultHolderBase*
  UntypedFunctionMockerBase::UntypedInvokeWith(const void* const untyped_args)
      GTEST_LOCK_EXCLUDED_(g_gmock_mutex) {
    if (untyped_expectations_.size() == 0) {
      // No expectation is set on this mock method - we have an
      // uninteresting call.
  
      // We must get Google Mock's reaction on uninteresting calls
      // made on this mock object BEFORE performing the action,
      // because the action may DELETE the mock object and make the
      // following expression meaningless.
      const CallReaction reaction =
          Mock::GetReactionOnUninterestingCalls(MockObject());
  
      // True iff we need to print this call's arguments and return
      // value.  This definition must be kept in sync with
      // the behavior of ReportUninterestingCall().
      const bool need_to_report_uninteresting_call =
          // If the user allows this uninteresting call, we print it
          // only when he wants informational messages.
          reaction == kAllow ? LogIsVisible(kInfo) :
          // If the user wants this to be a warning, we print it only
          // when he wants to see warnings.
          reaction == kWarn ? LogIsVisible(kWarning) :
          // Otherwise, the user wants this to be an error, and we
          // should always print detailed information in the error.
          true;
  
      if (!need_to_report_uninteresting_call) {
        // Perform the action without printing the call information.
        return this->UntypedPerformDefaultAction(untyped_args, "");
      }
  
      // Warns about the uninteresting call.
      ::std::stringstream ss;
      this->UntypedDescribeUninterestingCall(untyped_args, &ss);
  
      // Calculates the function result.
      UntypedActionResultHolderBase* const result =
          this->UntypedPerformDefaultAction(untyped_args, ss.str());
  
      // Prints the function result.
      if (result != NULL)
        result->PrintAsActionResult(&ss);
  
      ReportUninterestingCall(reaction, ss.str());
      return result;
    }
  
    bool is_excessive = false;
    ::std::stringstream ss;
    ::std::stringstream why;
    ::std::stringstream loc;
    const void* untyped_action = NULL;
  
    // The UntypedFindMatchingExpectation() function acquires and
    // releases g_gmock_mutex.
    const ExpectationBase* const untyped_expectation =
        this->UntypedFindMatchingExpectation(
            untyped_args, &untyped_action, &is_excessive,
            &ss, &why);
    const bool found = untyped_expectation != NULL;
  
    // True iff we need to print the call's arguments and return value.
    // This definition must be kept in sync with the uses of Expect()
    // and Log() in this function.
    const bool need_to_report_call =
        !found || is_excessive || LogIsVisible(kInfo);
    if (!need_to_report_call) {
      // Perform the action without printing the call information.
      return
          untyped_action == NULL ?
          this->UntypedPerformDefaultAction(untyped_args, "") :
          this->UntypedPerformAction(untyped_action, untyped_args);
    }
  
    ss << "    Function call: " << Name();
    this->UntypedPrintArgs(untyped_args, &ss);
  
    // In case the action deletes a piece of the expectation, we
    // generate the message beforehand.
    if (found && !is_excessive) {
      untyped_expectation->DescribeLocationTo(&loc);
    }
  
    UntypedActionResultHolderBase* const result =
        untyped_action == NULL ?
        this->UntypedPerformDefaultAction(untyped_args, ss.str()) :
        this->UntypedPerformAction(untyped_action, untyped_args);
    if (result != NULL)
      result->PrintAsActionResult(&ss);
    ss << "\n" << why.str();
  
    if (!found) {
      // No expectation matches this call - reports a failure.
      Expect(false, NULL, -1, ss.str());
    } else if (is_excessive) {
      // We had an upper-bound violation and the failure message is in ss.
      Expect(false, untyped_expectation->file(),
             untyped_expectation->line(), ss.str());
    } else {
      // We had an expected call and the matching expectation is
      // described in ss.
      Log(kInfo, loc.str() + ss.str(), 2);
    }
  
    return result;
  }
  
  // Returns an Expectation object that references and co-owns exp,
  // which must be an expectation on this mock function.
  Expectation UntypedFunctionMockerBase::GetHandleOf(ExpectationBase* exp) {
    for (UntypedExpectations::const_iterator it =
             untyped_expectations_.begin();
         it != untyped_expectations_.end(); ++it) {
      if (it->get() == exp) {
        return Expectation(*it);
      }
    }
  
    Assert(false, __FILE__, __LINE__, "Cannot find expectation.");
    return Expectation();
    // The above statement is just to make the code compile, and will
    // never be executed.
  }
  
  // Verifies that all expectations on this mock function have been
  // satisfied.  Reports one or more Google Test non-fatal failures
  // and returns false if not.
  bool UntypedFunctionMockerBase::VerifyAndClearExpectationsLocked()
      GTEST_EXCLUSIVE_LOCK_REQUIRED_(g_gmock_mutex) {
    g_gmock_mutex.AssertHeld();
    bool expectations_met = true;
    for (UntypedExpectations::const_iterator it =
             untyped_expectations_.begin();
         it != untyped_expectations_.end(); ++it) {
      ExpectationBase* const untyped_expectation = it->get();
      if (untyped_expectation->IsOverSaturated()) {
        // There was an upper-bound violation.  Since the error was
        // already reported when it occurred, there is no need to do
        // anything here.
        expectations_met = false;
      } else if (!untyped_expectation->IsSatisfied()) {
        expectations_met = false;
        ::std::stringstream ss;
        ss  << "Actual function call count doesn't match "
            << untyped_expectation->source_text() << "...\n";
        // No need to show the source file location of the expectation
        // in the description, as the Expect() call that follows already
        // takes care of it.
        untyped_expectation->MaybeDescribeExtraMatcherTo(&ss);
        untyped_expectation->DescribeCallCountTo(&ss);
        Expect(false, untyped_expectation->file(),
               untyped_expectation->line(), ss.str());
      }
    }
  
    // Deleting our expectations may trigger other mock objects to be deleted, for
    // example if an action contains a reference counted smart pointer to that
    // mock object, and that is the last reference. So if we delete our
    // expectations within the context of the global mutex we may deadlock when
    // this method is called again. Instead, make a copy of the set of
    // expectations to delete, clear our set within the mutex, and then clear the
    // copied set outside of it.
    UntypedExpectations expectations_to_delete;
    untyped_expectations_.swap(expectations_to_delete);
  
    g_gmock_mutex.Unlock();
    expectations_to_delete.clear();
    g_gmock_mutex.Lock();
  
    return expectations_met;
  }
  
  }  // namespace internal
  
  // Class Mock.
  
  namespace {
  
  typedef std::set<internal::UntypedFunctionMockerBase*> FunctionMockers;
  
  // The current state of a mock object.  Such information is needed for
  // detecting leaked mock objects and explicitly verifying a mock's
  // expectations.
  struct MockObjectState {
    MockObjectState()
        : first_used_file(NULL), first_used_line(-1), leakable(false) {}
  
    // Where in the source file an ON_CALL or EXPECT_CALL is first
    // invoked on this mock object.
    const char* first_used_file;
    int first_used_line;
    ::std::string first_used_test_case;
    ::std::string first_used_test;
    bool leakable;  // true iff it's OK to leak the object.
    FunctionMockers function_mockers;  // All registered methods of the object.
  };
  
  // A global registry holding the state of all mock objects that are
  // alive.  A mock object is added to this registry the first time
  // Mock::AllowLeak(), ON_CALL(), or EXPECT_CALL() is called on it.  It
  // is removed from the registry in the mock object's destructor.
  class MockObjectRegistry {
   public:
    // Maps a mock object (identified by its address) to its state.
    typedef std::map<const void*, MockObjectState> StateMap;
  
    // This destructor will be called when a program exits, after all
    // tests in it have been run.  By then, there should be no mock
    // object alive.  Therefore we report any living object as test
    // failure, unless the user explicitly asked us to ignore it.
    ~MockObjectRegistry() {
      // "using ::std::cout;" doesn't work with Symbian's STLport, where cout is
      // a macro.
  
      if (!GMOCK_FLAG(catch_leaked_mocks))
        return;
  
      int leaked_count = 0;
      for (StateMap::const_iterator it = states_.begin(); it != states_.end();
           ++it) {
        if (it->second.leakable)  // The user said it's fine to leak this object.
          continue;
  
        // TODO(wan@google.com): Print the type of the leaked object.
        // This can help the user identify the leaked object.
        std::cout << "\n";
        const MockObjectState& state = it->second;
        std::cout << internal::FormatFileLocation(state.first_used_file,
                                                  state.first_used_line);
        std::cout << " ERROR: this mock object";
        if (state.first_used_test != "") {
          std::cout << " (used in test " << state.first_used_test_case << "."
               << state.first_used_test << ")";
        }
        std::cout << " should be deleted but never is. Its address is @"
             << it->first << ".";
        leaked_count++;
      }
      if (leaked_count > 0) {
        std::cout << "\nERROR: " << leaked_count
             << " leaked mock " << (leaked_count == 1 ? "object" : "objects")
             << " found at program exit.\n";
        std::cout.flush();
        ::std::cerr.flush();
        // RUN_ALL_TESTS() has already returned when this destructor is
        // called.  Therefore we cannot use the normal Google Test
        // failure reporting mechanism.
        _exit(1);  // We cannot call exit() as it is not reentrant and
                   // may already have been called.
      }
    }
  
    StateMap& states() { return states_; }
  
   private:
    StateMap states_;
  };
  
  // Protected by g_gmock_mutex.
  MockObjectRegistry g_mock_object_registry;
  
  // Maps a mock object to the reaction Google Mock should have when an
  // uninteresting method is called.  Protected by g_gmock_mutex.
  std::map<const void*, internal::CallReaction> g_uninteresting_call_reaction;
  
  // Sets the reaction Google Mock should have when an uninteresting
  // method of the given mock object is called.
  void SetReactionOnUninterestingCalls(const void* mock_obj,
                                       internal::CallReaction reaction)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    internal::MutexLock l(&internal::g_gmock_mutex);
    g_uninteresting_call_reaction[mock_obj] = reaction;
  }
  
  }  // namespace
  
  // Tells Google Mock to allow uninteresting calls on the given mock
  // object.
  void Mock::AllowUninterestingCalls(const void* mock_obj)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    SetReactionOnUninterestingCalls(mock_obj, internal::kAllow);
  }
  
  // Tells Google Mock to warn the user about uninteresting calls on the
  // given mock object.
  void Mock::WarnUninterestingCalls(const void* mock_obj)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    SetReactionOnUninterestingCalls(mock_obj, internal::kWarn);
  }
  
  // Tells Google Mock to fail uninteresting calls on the given mock
  // object.
  void Mock::FailUninterestingCalls(const void* mock_obj)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    SetReactionOnUninterestingCalls(mock_obj, internal::kFail);
  }
  
  // Tells Google Mock the given mock object is being destroyed and its
  // entry in the call-reaction table should be removed.
  void Mock::UnregisterCallReaction(const void* mock_obj)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    internal::MutexLock l(&internal::g_gmock_mutex);
    g_uninteresting_call_reaction.erase(mock_obj);
  }
  
  // Returns the reaction Google Mock will have on uninteresting calls
  // made on the given mock object.
  internal::CallReaction Mock::GetReactionOnUninterestingCalls(
      const void* mock_obj)
          GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    internal::MutexLock l(&internal::g_gmock_mutex);
    return (g_uninteresting_call_reaction.count(mock_obj) == 0) ?
        internal::kDefault : g_uninteresting_call_reaction[mock_obj];
  }
  
  // Tells Google Mock to ignore mock_obj when checking for leaked mock
  // objects.
  void Mock::AllowLeak(const void* mock_obj)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    internal::MutexLock l(&internal::g_gmock_mutex);
    g_mock_object_registry.states()[mock_obj].leakable = true;
  }
  
  // Verifies and clears all expectations on the given mock object.  If
  // the expectations aren't satisfied, generates one or more Google
  // Test non-fatal failures and returns false.
  bool Mock::VerifyAndClearExpectations(void* mock_obj)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    internal::MutexLock l(&internal::g_gmock_mutex);
    return VerifyAndClearExpectationsLocked(mock_obj);
  }
  
  // Verifies all expectations on the given mock object and clears its
  // default actions and expectations.  Returns true iff the
  // verification was successful.
  bool Mock::VerifyAndClear(void* mock_obj)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    internal::MutexLock l(&internal::g_gmock_mutex);
    ClearDefaultActionsLocked(mock_obj);
    return VerifyAndClearExpectationsLocked(mock_obj);
  }
  
  // Verifies and clears all expectations on the given mock object.  If
  // the expectations aren't satisfied, generates one or more Google
  // Test non-fatal failures and returns false.
  bool Mock::VerifyAndClearExpectationsLocked(void* mock_obj)
      GTEST_EXCLUSIVE_LOCK_REQUIRED_(internal::g_gmock_mutex) {
    internal::g_gmock_mutex.AssertHeld();
    if (g_mock_object_registry.states().count(mock_obj) == 0) {
      // No EXPECT_CALL() was set on the given mock object.
      return true;
    }
  
    // Verifies and clears the expectations on each mock method in the
    // given mock object.
    bool expectations_met = true;
    FunctionMockers& mockers =
        g_mock_object_registry.states()[mock_obj].function_mockers;
    for (FunctionMockers::const_iterator it = mockers.begin();
         it != mockers.end(); ++it) {
      if (!(*it)->VerifyAndClearExpectationsLocked()) {
        expectations_met = false;
      }
    }
  
    // We don't clear the content of mockers, as they may still be
    // needed by ClearDefaultActionsLocked().
    return expectations_met;
  }
  
  // Registers a mock object and a mock method it owns.
  void Mock::Register(const void* mock_obj,
                      internal::UntypedFunctionMockerBase* mocker)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    internal::MutexLock l(&internal::g_gmock_mutex);
    g_mock_object_registry.states()[mock_obj].function_mockers.insert(mocker);
  }
  
  // Tells Google Mock where in the source code mock_obj is used in an
  // ON_CALL or EXPECT_CALL.  In case mock_obj is leaked, this
  // information helps the user identify which object it is.
  void Mock::RegisterUseByOnCallOrExpectCall(const void* mock_obj,
                                             const char* file, int line)
      GTEST_LOCK_EXCLUDED_(internal::g_gmock_mutex) {
    internal::MutexLock l(&internal::g_gmock_mutex);
    MockObjectState& state = g_mock_object_registry.states()[mock_obj];
    if (state.first_used_file == NULL) {
      state.first_used_file = file;
      state.first_used_line = line;
      const TestInfo* const test_info =
          UnitTest::GetInstance()->current_test_info();
      if (test_info != NULL) {
        // TODO(wan@google.com): record the test case name when the
        // ON_CALL or EXPECT_CALL is invoked from SetUpTestCase() or
        // TearDownTestCase().
        state.first_used_test_case = test_info->test_case_name();
        state.first_used_test = test_info->name();
      }
    }
  }
  
  // Unregisters a mock method; removes the owning mock object from the
  // registry when the last mock method associated with it has been
  // unregistered.  This is called only in the destructor of
  // FunctionMockerBase.
  void Mock::UnregisterLocked(internal::UntypedFunctionMockerBase* mocker)
      GTEST_EXCLUSIVE_LOCK_REQUIRED_(internal::g_gmock_mutex) {
    internal::g_gmock_mutex.AssertHeld();
    for (MockObjectRegistry::StateMap::iterator it =
             g_mock_object_registry.states().begin();
         it != g_mock_object_registry.states().end(); ++it) {
      FunctionMockers& mockers = it->second.function_mockers;
      if (mockers.erase(mocker) > 0) {
        // mocker was in mockers and has been just removed.
        if (mockers.empty()) {
          g_mock_object_registry.states().erase(it);
        }
        return;
      }
    }
  }
  
  // Clears all ON_CALL()s set on the given mock object.
  void Mock::ClearDefaultActionsLocked(void* mock_obj)
      GTEST_EXCLUSIVE_LOCK_REQUIRED_(internal::g_gmock_mutex) {
    internal::g_gmock_mutex.AssertHeld();
  
    if (g_mock_object_registry.states().count(mock_obj) == 0) {
      // No ON_CALL() was set on the given mock object.
      return;
    }
  
    // Clears the default actions for each mock method in the given mock
    // object.
    FunctionMockers& mockers =
        g_mock_object_registry.states()[mock_obj].function_mockers;
    for (FunctionMockers::const_iterator it = mockers.begin();
         it != mockers.end(); ++it) {
      (*it)->ClearDefaultActionsLocked();
    }
  
    // We don't clear the content of mockers, as they may still be
    // needed by VerifyAndClearExpectationsLocked().
  }
  
  Expectation::Expectation() {}
  
  Expectation::Expectation(
      const internal::linked_ptr<internal::ExpectationBase>& an_expectation_base)
      : expectation_base_(an_expectation_base) {}
  
  Expectation::~Expectation() {}
  
  // Adds an expectation to a sequence.
  void Sequence::AddExpectation(const Expectation& expectation) const {
    if (*last_expectation_ != expectation) {
      if (last_expectation_->expectation_base() != NULL) {
        expectation.expectation_base()->immediate_prerequisites_
            += *last_expectation_;
      }
      *last_expectation_ = expectation;
    }
  }
  
  // Creates the implicit sequence if there isn't one.
  InSequence::InSequence() {
    if (internal::g_gmock_implicit_sequence.get() == NULL) {
      internal::g_gmock_implicit_sequence.set(new Sequence);
      sequence_created_ = true;
    } else {
      sequence_created_ = false;
    }
  }
  
  // Deletes the implicit sequence if it was created by the constructor
  // of this object.
  InSequence::~InSequence() {
    if (sequence_created_) {
      delete internal::g_gmock_implicit_sequence.get();
      internal::g_gmock_implicit_sequence.set(NULL);
    }
  }
  
  }  // namespace testing
  // Copyright 2008, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Author: wan@google.com (Zhanyong Wan)
  
  
  namespace testing {
  
  // TODO(wan@google.com): support using environment variables to
  // control the flag values, like what Google Test does.
  
  GMOCK_DEFINE_bool_(catch_leaked_mocks, true,
                     "true iff Google Mock should report leaked mock objects "
                     "as failures.");
  
  GMOCK_DEFINE_string_(verbose, internal::kWarningVerbosity,
                       "Controls how verbose Google Mock's output is."
                       "  Valid values:\n"
                       "  info    - prints all messages.\n"
                       "  warning - prints warnings and errors.\n"
                       "  error   - prints errors only.");
  
  namespace internal {
  
  // Parses a string as a command line flag.  The string should have the
  // format "--gmock_flag=value".  When def_optional is true, the
  // "=value" part can be omitted.
  //
  // Returns the value of the flag, or NULL if the parsing failed.
  static const char* ParseGoogleMockFlagValue(const char* str,
                                              const char* flag,
                                              bool def_optional) {
    // str and flag must not be NULL.
    if (str == NULL || flag == NULL) return NULL;
  
    // The flag must start with "--gmock_".
    const std::string flag_str = std::string("--gmock_") + flag;
    const size_t flag_len = flag_str.length();
    if (strncmp(str, flag_str.c_str(), flag_len) != 0) return NULL;
  
    // Skips the flag name.
    const char* flag_end = str + flag_len;
  
    // When def_optional is true, it's OK to not have a "=value" part.
    if (def_optional && (flag_end[0] == '\0')) {
      return flag_end;
    }
  
    // If def_optional is true and there are more characters after the
    // flag name, or if def_optional is false, there must be a '=' after
    // the flag name.
    if (flag_end[0] != '=') return NULL;
  
    // Returns the string after "=".
    return flag_end + 1;
  }
  
  // Parses a string for a Google Mock bool flag, in the form of
  // "--gmock_flag=value".
  //
  // On success, stores the value of the flag in *value, and returns
  // true.  On failure, returns false without changing *value.
  static bool ParseGoogleMockBoolFlag(const char* str, const char* flag,
                                      bool* value) {
    // Gets the value of the flag as a string.
    const char* const value_str = ParseGoogleMockFlagValue(str, flag, true);
  
    // Aborts if the parsing failed.
    if (value_str == NULL) return false;
  
    // Converts the string value to a bool.
    *value = !(*value_str == '0' || *value_str == 'f' || *value_str == 'F');
    return true;
  }
  
  // Parses a string for a Google Mock string flag, in the form of
  // "--gmock_flag=value".
  //
  // On success, stores the value of the flag in *value, and returns
  // true.  On failure, returns false without changing *value.
  template <typename String>
  static bool ParseGoogleMockStringFlag(const char* str, const char* flag,
                                        String* value) {
    // Gets the value of the flag as a string.
    const char* const value_str = ParseGoogleMockFlagValue(str, flag, false);
  
    // Aborts if the parsing failed.
    if (value_str == NULL) return false;
  
    // Sets *value to the value of the flag.
    *value = value_str;
    return true;
  }
  
  // The internal implementation of InitGoogleMock().
  //
  // The type parameter CharType can be instantiated to either char or
  // wchar_t.
  template <typename CharType>
  void InitGoogleMockImpl(int* argc, CharType** argv) {
    // Makes sure Google Test is initialized.  InitGoogleTest() is
    // idempotent, so it's fine if the user has already called it.
    InitGoogleTest(argc, argv);
    if (*argc <= 0) return;
  
    for (int i = 1; i != *argc; i++) {
      const std::string arg_string = StreamableToString(argv[i]);
      const char* const arg = arg_string.c_str();
  
      // Do we see a Google Mock flag?
      if (ParseGoogleMockBoolFlag(arg, "catch_leaked_mocks",
                                  &GMOCK_FLAG(catch_leaked_mocks)) ||
          ParseGoogleMockStringFlag(arg, "verbose", &GMOCK_FLAG(verbose))) {
        // Yes.  Shift the remainder of the argv list left by one.  Note
        // that argv has (*argc + 1) elements, the last one always being
        // NULL.  The following loop moves the trailing NULL element as
        // well.
        for (int j = i; j != *argc; j++) {
          argv[j] = argv[j + 1];
        }
  
        // Decrements the argument count.
        (*argc)--;
  
        // We also need to decrement the iterator as we just removed
        // an element.
        i--;
      }
    }
  }
  
  }  // namespace internal
  
  // Initializes Google Mock.  This must be called before running the
  // tests.  In particular, it parses a command line for the flags that
  // Google Mock recognizes.  Whenever a Google Mock flag is seen, it is
  // removed from argv, and *argc is decremented.
  //
  // No value is returned.  Instead, the Google Mock flag variables are
  // updated.
  //
  // Since Google Test is needed for Google Mock to work, this function
  // also initializes Google Test and parses its flags, if that hasn't
  // been done.
  GTEST_API_ void InitGoogleMock(int* argc, char** argv) {
    internal::InitGoogleMockImpl(argc, argv);
  }
  
  // This overloaded version can be used in Windows programs compiled in
  // UNICODE mode.
  GTEST_API_ void InitGoogleMock(int* argc, wchar_t** argv) {
    internal::InitGoogleMockImpl(argc, argv);
  }
  
  }  // namespace testing
  