text: // 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)
  
  #include "gtest/gtest.h"
  #include "gtest/internal/custom/gtest.h"
  #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
  
  // 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().
  #  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().
  # 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
  #include "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 test too, in addition to the test 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 test to run, optionally followed by a "
      "'-' and a : separated list of negative patterns (test 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 test 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 test.");
  
  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 test' 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).
    // Use wider types than necessary to prevent unsigned overflow diagnostics.
    state_ = static_cast<UInt32>(1103515245ULL*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())
      // 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 std::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 std::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 test.
  int UnitTestImpl::successful_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::successful_test_count);
  }
  
  // Gets the number of failed test.
  int UnitTestImpl::failed_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::failed_test_count);
  }
  
  // Gets the number of disabled test 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 test.
  int UnitTestImpl::disabled_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::disabled_test_count);
  }
  
  // Gets the number of test 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 test.
  int UnitTestImpl::total_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::total_test_count);
  }
  
  // Gets the number of test 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;
  
    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.
  
    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 omitted 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:
  //
  //   lhs_expression: "foo"
  //   rhs_expression: "bar"
  //   lhs_value:      "5"
  //   rhs_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* lhs_expression,
                            const char* rhs_expression,
                            const std::string& lhs_value,
                            const std::string& rhs_value,
                            bool ignoring_case) {
    Message msg;
    msg << "      Expected: " << lhs_expression;
    if (lhs_value != lhs_expression) {
      msg << "\n      Which is: " << lhs_value;
    }
    msg << "\nTo be equal to: " << rhs_expression;
    if (rhs_value != rhs_expression) {
      msg << "\n      Which is: " << rhs_value;
    }
  
    if (ignoring_case) {
      msg << "\nIgnoring case";
    }
  
    if (!lhs_value.empty() && !rhs_value.empty()) {
      const std::vector<std::string> lhs_lines =
          SplitEscapedString(lhs_value);
      const std::vector<std::string> rhs_lines =
          SplitEscapedString(rhs_value);
      if (lhs_lines.size() > 1 || rhs_lines.size() > 1) {
        msg << "\nWith diff:\n"
            << edit_distance::CreateUnifiedDiff(lhs_lines, rhs_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();
  
    // 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* lhs_expression,
                              const char* rhs_expression,
                              BiggestInt lhs,
                              BiggestInt rhs) {
    if (lhs == rhs) {
      return AssertionSuccess();
    }
  
    return EqFailure(lhs_expression,
                     rhs_expression,
                     FormatForComparisonFailureMessage(lhs, rhs),
                     FormatForComparisonFailureMessage(rhs, lhs),
                     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* lhs_expression,
                                 const char* rhs_expression,
                                 const char* lhs,
                                 const char* rhs) {
    if (String::CStringEquals(lhs, rhs)) {
      return AssertionSuccess();
    }
  
    return EqFailure(lhs_expression,
                     rhs_expression,
                     PrintToString(lhs),
                     PrintToString(rhs),
                     false);
  }
  
  // The helper function for {ASSERT|EXPECT}_STRCASEEQ.
  AssertionResult CmpHelperSTRCASEEQ(const char* lhs_expression,
                                     const char* rhs_expression,
                                     const char* lhs,
                                     const char* rhs) {
    if (String::CaseInsensitiveCStringEquals(lhs, rhs)) {
      return AssertionSuccess();
    }
  
    return EqFailure(lhs_expression,
                     rhs_expression,
                     PrintToString(lhs),
                     PrintToString(rhs),
                     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 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* lhs_expression,
                                 const char* rhs_expression,
                                 const wchar_t* lhs,
                                 const wchar_t* rhs) {
    if (String::WideCStringEquals(lhs, rhs)) {
      return AssertionSuccess();
    }
  
    return EqFailure(lhs_expression,
                     rhs_expression,
                     PrintToString(lhs),
                     PrintToString(rhs),
                     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",
    "test",
    "time",
    "timestamp"
  };
  
  // The list of reserved attributes used in the <testsuite> element of XML
  // output.
  static const char* const kReservedTestSuiteAttributes[] = {
    "disabled",
    "errors",
    "failures",
    "name",
    "test",
    "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 test 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 test.
        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 test 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 test 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 test 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 test 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 test 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 test registered with macros TEST_P
  // and INSTANTIATE_TEST_CASE_P into regular test 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 test in this test case.
  int TestCase::successful_test_count() const {
    return CountIf(test_info_list_, TestPassed);
  }
  
  // Gets the number of failed test in this test case.
  int TestCase::failed_test_count() const {
    return CountIf(test_info_list_, TestFailed);
  }
  
  // Gets the number of disabled test 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 test in this test case.
  int TestCase::disabled_test_count() const {
    return CountIf(test_info_list_, TestDisabled);
  }
  
  // Gets the number of test to be printed in the XML report.
  int TestCase::reportable_test_count() const {
    return CountIf(test_info_list_, TestReportable);
  }
  
  // Get the number of test 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 test.
  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 test. 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 test. 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 test in this test case.
  void TestCase::ClearResult() {
    ad_hoc_test_result_.Clear();
    ForEach(test_info_list_, TestInfo::ClearTestResult);
  }
  
  // Shuffles the test 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 test.
  static std::string FormatTestCount(int test_count) {
    return FormatCountableNoun(test_count, "test", "test");
  }
  
  // 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;
    }
  }
  
  int GetBitOffset(WORD color_mask) {
    if (color_mask == 0) return 0;
  
    int bitOffset = 0;
    while((color_mask & 1) == 0) {
      color_mask >>= 1;
      ++bitOffset;
    }
    return bitOffset;
  }
  
  WORD GetNewColor(GTestColor color, WORD old_color_attrs) {
    // Let's reuse the BG
    static const WORD background_mask = BACKGROUND_BLUE | BACKGROUND_GREEN | BACKGROUND_RED | BACKGROUND_INTENSITY;
    static const WORD foreground_mask = FOREGROUND_BLUE | FOREGROUND_GREEN | FOREGROUND_RED | FOREGROUND_INTENSITY;
    const WORD existing_bg = old_color_attrs & background_mask;
  
    WORD new_color = GetColorAttribute(color) | existing_bg | FOREGROUND_INTENSITY;
    static const int bg_bitOffset = GetBitOffset(background_mask);
    static const int fg_bitOffset = GetBitOffset(foreground_mask);
  
    if (((new_color & background_mask) >> bg_bitOffset) == ((new_color & foreground_mask) >> fg_bitOffset)) {
      new_color ^= FOREGROUND_INTENSITY; //invert intensity
    }
    return new_color;
  }
  	
  #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, "tmux") ||
          String::CStringEquals(term, "tmux-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.
  GTEST_ATTRIBUTE_PRINTF_(2, 3)
  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;
    const WORD new_color = GetNewColor(color, old_color_attrs);
    
    // 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, new_color);
  
    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 test starts.
  void PrettyUnitTestResultPrinter::OnTestIterationStart(
      const UnitTest& unit_test, int iteration) {
    if (GTEST_FLAG(repeat) != 1)
      printf("\nRepeating all test (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
    // test 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 test' 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", "test");
    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", "test");
    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 test.
  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);
  }
  
  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) {
      //
      // 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.
  // 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.
  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 std::string location =
            internal::FormatCompilerIndependentFileLocation(part.file_name(),
                                                            part.line_number());
        const std::string summary = location + "\n" + part.summary();
        *stream << "      <failure message=\""
                << EscapeXmlAttribute(summary.c_str())
                << "\" type=\"\">";
        const std::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, "test",
                       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, "test",
                       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.
  std::string StreamingListener::UrlEncode(const char* str) {
    std::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 ...";
  
  std::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 test 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 test.
  int UnitTest::successful_test_count() const {
    return impl()->successful_test_count();
  }
  
  // Gets the number of failed test.
  int UnitTest::failed_test_count() const { return impl()->failed_test_count(); }
  
  // Gets the number of disabled test 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 test.
  int UnitTest::disabled_test_count() const {
    return impl()->disabled_test_count();
  }
  
  // Gets the number of test to be printed in the XML report.
  int UnitTest::reportable_test_count() const {
    return impl()->reportable_test_count();
  }
  
  // Gets the number of all test.
  int UnitTest::total_test_count() const { return impl()->total_test_count(); }
  
  // Gets the number of test 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 test 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 test 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 test 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
    // test 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.
      // 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 test 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 test. This makes parameterized test
      // 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 test in this UnitTest object, prints the result, and
  // returns true if all test are successful.  If any exception is
  // thrown during a test, the test is considered to be failed, but the
  // rest of the test will still be run.
  //
  // When parameterized test are enabled, it expands and registers
  // parameterized test first in RegisterParameterizedTests().
  // All other functions called from RunAllTests() may safely assume that
  // parameterized test 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
    // test to run.
    const bool has_tests_to_run = FilterTests(should_shard
                                                ? HONOR_SHARDING_PROTOCOL
                                                : IGNORE_SHARDING_PROTOCOL) > 0;
  
    // Lists the test 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 test?  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 test 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 test 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 test 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 test 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 test).
      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 test 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, "%s", 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, "%s", 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, "%s", 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 test based on sharding
  // variables in the environment - see
  // https://github.com/google/googletest/blob/master/googletest/docs/AdvancedGuide.md .
  // Returns the number of test 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 test that will
    // run across all shards (i.e., match filter and are not disabled).
    // num_selected_tests are the number of test 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 test 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 test within each test case,
  // making sure that death test 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 test inside each test case.
    for (size_t i = 0; i < test_cases_.size(); i++) {
      test_cases_[i]->ShuffleTests(random());
    }
  }
  
  // Restores the test cases and test to their order before the first shuffle.
  void UnitTestImpl::UnshuffleTests() {
    for (size_t i = 0; i < test_cases_.size(); i++) {
      // Unshuffles the test 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.
  //
  // 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 test 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 test 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 test 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 test too.\n"
  "\n"
  "Test Execution:\n"
  "  @G--" GTEST_FLAG_PREFIX_ "repeat=@Y[COUNT]@D\n"
  "      Run the test repeatedly; use a negative count to repeat forever.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "shuffle@D\n"
  "      Randomize test' 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_detail.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 test), 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_)
  }
  
  std::string TempDir() {
  #if defined(GTEST_CUSTOM_TEMPDIR_FUNCTION_)
      return GTEST_CUSTOM_TEMPDIR_FUNCTION_();
  #endif
  #if GTEST_OS_WINDOWS_MOBILE
    return "\\temp\\";
  #elif GTEST_OS_WINDOWS
    const char* temp_dir = internal::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
  }
  
  }  // namespace testing
  