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/gtest-spi.h>
  
  #include <ctype.h>
  #include <math.h>
  #include <stdarg.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <wchar.h>
  #include <wctype.h>
  
  #include <ostream>
  
  #if GTEST_OS_LINUX
  
  // TODO(kenton@google.com): Use autoconf to detect availability of
  // gettimeofday().
  #define GTEST_HAS_GETTIMEOFDAY_ 1
  
  #include <fcntl.h>
  #include <limits.h>
  #include <sched.h>
  // Declares vsnprintf().  This header is not available on Windows.
  #include <strings.h>
  #include <sys/mman.h>
  #include <sys/time.h>
  #include <unistd.h>
  #include <string>
  #include <vector>
  
  #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
  
  #elif GTEST_OS_WINDOWS  // We are on Windows proper.
  
  #include <io.h>  // NOLINT
  #include <sys/timeb.h>  // NOLINT
  #include <sys/types.h>  // NOLINT
  #include <sys/stat.h>  // NOLINT
  
  #if GTEST_OS_WINDOWS_MINGW
  // MinGW has gettimeofday() but not _ftime64().
  // TODO(kenton@google.com): Use autoconf to detect availability of
  //   gettimeofday().
  // TODO(kenton@google.com): There are other ways to get the time on
  //   Windows, like GetTickCount() or GetSystemTimeAsFileTime().  MinGW
  //   supports these.  consider using them instead.
  #define GTEST_HAS_GETTIMEOFDAY_ 1
  #include <sys/time.h>  // NOLINT
  #endif  // GTEST_OS_WINDOWS_MINGW
  
  // cpplint thinks that the header is already included, so we want to
  // silence it.
  #include <windows.h>  // NOLINT
  
  #else
  
  // Assume other platforms have gettimeofday().
  // TODO(kenton@google.com): Use autoconf to detect availability of
  //   gettimeofday().
  #define GTEST_HAS_GETTIMEOFDAY_ 1
  
  // cpplint thinks that the header is already included, so we want to
  // silence it.
  #include <sys/time.h>  // NOLINT
  #include <unistd.h>  // NOLINT
  
  #endif  // GTEST_OS_LINUX
  
  #if GTEST_HAS_EXCEPTIONS
  #include <stdexcept>
  #endif
  
  // 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 "src/gtest-internal-inl.h"
  #undef GTEST_IMPLEMENTATION_
  
  #if GTEST_OS_WINDOWS
  #define vsnprintf _vsnprintf
  #endif  // GTEST_OS_WINDOWS
  
  namespace testing {
  
  // 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";
  
  }  // namespace internal
  
  GTEST_DEFINE_bool_(
      also_run_disabled_tests,
      internal::BoolFromGTestEnv("also_run_disabled_tests", false),
      "Run disabled tests too, in addition to the tests normally being run.");
  
  GTEST_DEFINE_bool_(
      break_on_failure,
      internal::BoolFromGTestEnv("break_on_failure", false),
      "True iff a failed assertion should be a debugger break-point.");
  
  GTEST_DEFINE_bool_(
      catch_exceptions,
      internal::BoolFromGTestEnv("catch_exceptions", false),
      "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 xterm, xterm-color, xterm-256color, linux or cygwin.");
  
  GTEST_DEFINE_string_(
      filter,
      internal::StringFromGTestEnv("filter", kUniversalFilter),
      "A colon-separated list of glob (not regex) patterns "
      "for filtering the tests to run, optionally followed by a "
      "'-' and a : separated list of negative patterns (tests to "
      "exclude).  A test is run if it matches one of the positive "
      "patterns and does not match any of the negative patterns.");
  
  GTEST_DEFINE_bool_(list_tests, false,
                     "List all tests without running them.");
  
  GTEST_DEFINE_string_(
      output,
      internal::StringFromGTestEnv("output", ""),
      "A format (currently must be \"xml\"), optionally followed "
      "by a colon and an output file name or directory. A directory "
      "is indicated by a trailing pathname separator. "
      "Examples: \"xml:filename.xml\", \"xml::directoryname/\". "
      "If a directory is specified, output files will be created "
      "within that directory, with file-names based on the test "
      "executable's name and, if necessary, made unique by adding "
      "digits.");
  
  GTEST_DEFINE_bool_(
      print_time,
      internal::BoolFromGTestEnv("print_time", true),
      "True iff " GTEST_NAME_
      " should display elapsed time in text output.");
  
  GTEST_DEFINE_int32_(
      random_seed,
      internal::Int32FromGTestEnv("random_seed", 0),
      "Random number seed to use when shuffling test orders.  Must be in range "
      "[1, 99999], or 0 to use a seed based on the current time.");
  
  GTEST_DEFINE_int32_(
      repeat,
      internal::Int32FromGTestEnv("repeat", 1),
      "How many times to repeat each test.  Specify a negative number "
      "for repeating forever.  Useful for shaking out flaky tests.");
  
  GTEST_DEFINE_bool_(
      show_internal_stack_frames, false,
      "True iff " GTEST_NAME_ " should include internal stack frames when "
      "printing test failure stack traces.");
  
  GTEST_DEFINE_bool_(
      shuffle,
      internal::BoolFromGTestEnv("shuffle", false),
      "True iff " GTEST_NAME_
      " should randomize tests' order on every run.");
  
  GTEST_DEFINE_int32_(
      stack_trace_depth,
          internal::Int32FromGTestEnv("stack_trace_depth", kMaxStackTraceDepth),
      "The maximum number of stack frames to print when an "
      "assertion fails.  The valid range is 0 through 100, inclusive.");
  
  GTEST_DEFINE_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.");
  
  namespace internal {
  
  // Generates a random number from [0, range), using a Linear
  // Congruential Generator (LCG).  Crashes if 'range' is 0 or greater
  // than kMaxRange.
  UInt32 Random::Generate(UInt32 range) {
    // These constants are the same as are used in glibc's rand(3).
    state_ = (1103515245U*state_ + 12345U) % kMaxRange;
  
    GTEST_CHECK_(range > 0)
        << "Cannot generate a number in the range [0, 0).";
    GTEST_CHECK_(range <= kMaxRange)
        << "Generation of a number in [0, " << range << ") was requested, "
        << "but this can only generate numbers in [0, " << kMaxRange << ").";
  
    // Converting via modulus introduces a bit of downward bias, but
    // it's simple, and a linear congruential generator isn't too good
    // to begin with.
    return state_ % range;
  }
  
  // g_help_flag is true iff the --help flag or an equivalent form is
  // specified on the command line.
  static bool g_help_flag = false;
  
  // 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().
  //
  // A user must call testing::InitGoogleTest() to initialize Google
  // Test.  g_init_gtest_count is set to the number of times
  // InitGoogleTest() has been called.  We don't protect this variable
  // under a mutex as it is only accessed in the main thread.
  int g_init_gtest_count = 0;
  static bool GTestIsInitialized() { return g_init_gtest_count != 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 internal::Vector<TestCase*>& case_list,
                                 int (TestCase::*method)() const) {
    int sum = 0;
    for (int i = 0; i < case_list.size(); i++) {
      sum += (case_list.GetElement(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.
  Mutex g_linked_ptr_mutex(Mutex::NO_CONSTRUCTOR_NEEDED_FOR_STATIC_MUTEX);
  
  // Application pathname gotten in InitGoogleTest.
  String g_executable_path;
  
  // Returns the current application's name, removing directory path if that
  // is present.
  FilePath GetCurrentExecutableName() {
    FilePath result;
  
  #if GTEST_OS_WINDOWS
    result.Set(FilePath(g_executable_path).RemoveExtension("exe"));
  #else
    result.Set(FilePath(g_executable_path));
  #endif  // GTEST_OS_WINDOWS
  
    return result.RemoveDirectoryName();
  }
  
  // Functions for processing the gtest_output flag.
  
  // Returns the output format, or "" for normal printed output.
  String UnitTestOptions::GetOutputFormat() {
    const char* const gtest_output_flag = GTEST_FLAG(output).c_str();
    if (gtest_output_flag == NULL) return String("");
  
    const char* const colon = strchr(gtest_output_flag, ':');
    return (colon == NULL) ?
        String(gtest_output_flag) :
        String(gtest_output_flag, colon - gtest_output_flag);
  }
  
  // Returns the name of the requested output file, or the default if none
  // was explicitly specified.
  String UnitTestOptions::GetAbsolutePathToOutputFile() {
    const char* const gtest_output_flag = GTEST_FLAG(output).c_str();
    if (gtest_output_flag == NULL)
      return String("");
  
    const char* const colon = strchr(gtest_output_flag, ':');
    if (colon == NULL)
      return String(internal::FilePath::ConcatPaths(
                 internal::FilePath(
                     UnitTest::GetInstance()->original_working_dir()),
                 internal::FilePath(kDefaultOutputFile)).ToString() );
  
    internal::FilePath output_name(colon + 1);
    if (!output_name.IsAbsolutePath())
      // TODO(wan@google.com): on Windows \some\path is not an absolute
      // path (as its meaning depends on the current drive), yet the
      // following logic for turning it into an absolute path is wrong.
      // Fix it.
      output_name = internal::FilePath::ConcatPaths(
          internal::FilePath(UnitTest::GetInstance()->original_working_dir()),
          internal::FilePath(colon + 1));
  
    if (!output_name.IsDirectory())
      return output_name.ToString();
  
    internal::FilePath result(internal::FilePath::GenerateUniqueFileName(
        output_name, internal::GetCurrentExecutableName(),
        GetOutputFormat().c_str()));
    return result.ToString();
  }
  
  // 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 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++;
    }
  }
  
  // TODO(keithray): move String function implementations to gtest-string.cc.
  
  // Returns true iff the user-specified filter matches the test case
  // name and the test name.
  bool UnitTestOptions::FilterMatchesTest(const String &test_case_name,
                                          const String &test_name) {
    const String& full_name = String::Format("%s.%s",
                                             test_case_name.c_str(),
                                             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, '-');
    String positive;
    String negative;
    if (dash == NULL) {
      positive = GTEST_FLAG(filter).c_str();  // Whole string is a positive filter
      negative = String("");
    } else {
      positive = String(p, dash - p);  // Everything up to the dash
      negative = 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_OS_WINDOWS
  // 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 an exception if:
    //   1. the user wants it to, AND
    //   2. this is not a breakpoint exception.
    return (GTEST_FLAG(catch_exceptions) &&
            exception_code != EXCEPTION_BREAKPOINT) ?
        EXCEPTION_EXECUTE_HANDLER :
        EXCEPTION_CONTINUE_SEARCH;
  }
  #endif  // GTEST_OS_WINDOWS
  
  }  // 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 char* substr) {
    const 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) {
      msg << "Expected: " << expected << "\n"
          << "  Actual:\n"
          << r;
      return AssertionFailure(msg);
    }
  
    if (strstr(r.message(), substr) == NULL) {
      msg << "Expected: " << expected << " containing \""
          << substr << "\"\n"
          << "  Actual:\n"
          << r;
      return AssertionFailure(msg);
    }
  
    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 char* 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_.c_str());
  }
  
  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 test_cases_.CountIf(TestCasePassed);
  }
  
  // Gets the number of failed test cases.
  int UnitTestImpl::failed_test_case_count() const {
    return test_cases_.CountIf(TestCaseFailed);
  }
  
  // Gets the number of all test cases.
  int UnitTestImpl::total_test_case_count() const {
    return 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 test_cases_.CountIf(ShouldRunTestCase);
  }
  
  // Gets the number of successful tests.
  int UnitTestImpl::successful_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::successful_test_count);
  }
  
  // Gets the number of failed tests.
  int UnitTestImpl::failed_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::failed_test_count);
  }
  
  // Gets the number of disabled tests.
  int UnitTestImpl::disabled_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::disabled_test_count);
  }
  
  // Gets the number of all tests.
  int UnitTestImpl::total_test_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::total_test_count);
  }
  
  // Gets the number of tests that should run.
  int UnitTestImpl::test_to_run_count() const {
    return SumOverTestCaseList(test_cases_, &TestCase::test_to_run_count);
  }
  
  // Returns the current OS stack trace as a 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.
  String UnitTestImpl::CurrentOsStackTraceExceptTop(int skip_count) {
    (void)skip_count;
    return String("");
  }
  
  // Returns the current time in milliseconds.
  TimeInMillis GetTimeInMillis() {
  #if GTEST_OS_WINDOWS_MOBILE || defined(__BORLANDC__)
    // Difference between 1970-01-01 and 1601-01-01 in milliseconds.
    // http://analogous.blogspot.com/2005/04/epoch.html
    const TimeInMillis kJavaEpochToWinFileTimeDelta =
      static_cast<TimeInMillis>(116444736UL) * 100000UL;
    const DWORD kTenthMicrosInMilliSecond = 10000;
  
    SYSTEMTIME now_systime;
    FILETIME now_filetime;
    ULARGE_INTEGER now_int64;
    // TODO(kenton@google.com): Shouldn't this just use
    //   GetSystemTimeAsFileTime()?
    GetSystemTime(&now_systime);
    if (SystemTimeToFileTime(&now_systime, &now_filetime)) {
      now_int64.LowPart = now_filetime.dwLowDateTime;
      now_int64.HighPart = now_filetime.dwHighDateTime;
      now_int64.QuadPart = (now_int64.QuadPart / kTenthMicrosInMilliSecond) -
        kJavaEpochToWinFileTimeDelta;
      return now_int64.QuadPart;
    }
    return 0;
  #elif GTEST_OS_WINDOWS && !GTEST_HAS_GETTIMEOFDAY_
    __timeb64 now;
  #ifdef _MSC_VER
    // MSVC 8 deprecates _ftime64(), so we want to suppress warning 4996
    // (deprecated function) there.
    // TODO(kenton@google.com): Use GetTickCount()?  Or use
    //   SystemTimeToFileTime()
  #pragma warning(push)          // Saves the current warning state.
  #pragma warning(disable:4996)  // Temporarily disables warning 4996.
    _ftime64(&now);
  #pragma warning(pop)           // Restores the warning state.
  #else
    _ftime64(&now);
  #endif  // _MSC_VER
    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
  
  // Returns the input enclosed in double quotes if it's not NULL;
  // otherwise returns "(null)".  For example, "\"Hello\"" is returned
  // for input "Hello".
  //
  // This is useful for printing a C string in the syntax of a literal.
  //
  // Known issue: escape sequences are not handled yet.
  String String::ShowCStringQuoted(const char* c_str) {
    return c_str ? String::Format("\"%s\"", c_str) : String("(null)");
  }
  
  // Copies at most length characters from str into a newly-allocated
  // piece of memory of size length+1.  The memory is allocated with new[].
  // A terminating null byte is written to the memory, and a pointer to it
  // is returned.  If str is NULL, NULL is returned.
  static char* CloneString(const char* str, size_t length) {
    if (str == NULL) {
      return NULL;
    } else {
      char* const clone = new char[length + 1];
      posix::StrNCpy(clone, str, length);
      clone[length] = '\0';
      return clone;
    }
  }
  
  // Clones a 0-terminated C string, allocating memory using new.  The
  // caller is responsible for deleting[] the return value.  Returns the
  // cloned string, or NULL if the input is NULL.
  const char * String::CloneCString(const char* c_str) {
    return (c_str == NULL) ?
                      NULL : CloneString(c_str, strlen(c_str));
  }
  
  #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) {
    // TODO(wan): consider allowing a testing::String object to
    // contain '\0'.  This will make it behave more like std::string,
    // and will allow ToUtf8String() to return the correct encoding
    // for '\0' s.t. we can get rid of the conditional here (and in
    // several other places).
    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
  
  }  // namespace internal
  
  #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
  
  namespace internal {
  
  // Formats a value to be used in a failure message.
  
  // For a char value, we print it as a C++ char literal and as an
  // unsigned integer (both in decimal and in hexadecimal).
  String FormatForFailureMessage(char ch) {
    const unsigned int ch_as_uint = ch;
    // A String object cannot contain '\0', so we print "\\0" when ch is
    // '\0'.
    return String::Format("'%s' (%u, 0x%X)",
                          ch ? String::Format("%c", ch).c_str() : "\\0",
                          ch_as_uint, ch_as_uint);
  }
  
  // For a wchar_t value, we print it as a C++ wchar_t literal and as an
  // unsigned integer (both in decimal and in hexidecimal).
  String FormatForFailureMessage(wchar_t wchar) {
    // The C++ standard doesn't specify the exact size of the wchar_t
    // type.  It just says that it shall have the same size as another
    // integral type, called its underlying type.
    //
    // Therefore, in order to print a wchar_t value in the numeric form,
    // we first convert it to the largest integral type (UInt64) and
    // then print the converted value.
    //
    // We use streaming to print the value as "%llu" doesn't work
    // correctly with MSVC 7.1.
    const UInt64 wchar_as_uint64 = wchar;
    Message msg;
    // A String object cannot contain '\0', so we print "\\0" when wchar is
    // L'\0'.
    char buffer[32];  // CodePointToUtf8 requires a buffer that big.
    msg << "L'"
        << (wchar ? CodePointToUtf8(static_cast<UInt32>(wchar), buffer) : "\\0")
        << "' (" << wchar_as_uint64 << ", 0x" << ::std::setbase(16)
        << wchar_as_uint64 << ")";
    return msg.GetString();
  }
  
  }  // namespace internal
  
  // AssertionResult constructor.
  AssertionResult::AssertionResult(const internal::String& failure_message)
      : failure_message_(failure_message) {
  }
  
  
  // Makes a successful assertion result.
  AssertionResult AssertionSuccess() {
    return AssertionResult();
  }
  
  
  // Makes a failed assertion result with the given failure message.
  AssertionResult AssertionFailure(const Message& message) {
    return AssertionResult(message.GetString());
  }
  
  namespace internal {
  
  // Constructs and returns the message for an equality assertion
  // (e.g. ASSERT_EQ, EXPECT_STREQ, etc) failure.
  //
  // The first four parameters are the expressions used in the assertion
  // and their values, as strings.  For example, for ASSERT_EQ(foo, bar)
  // where foo is 5 and bar is 6, we have:
  //
  //   expected_expression: "foo"
  //   actual_expression:   "bar"
  //   expected_value:      "5"
  //   actual_value:        "6"
  //
  // The ignoring_case parameter is true iff the assertion is a
  // *_STRCASEEQ*.  When it's true, the string " (ignoring case)" will
  // be inserted into the message.
  AssertionResult EqFailure(const char* expected_expression,
                            const char* actual_expression,
                            const String& expected_value,
                            const String& actual_value,
                            bool ignoring_case) {
    Message msg;
    msg << "Value of: " << actual_expression;
    if (actual_value != actual_expression) {
      msg << "\n  Actual: " << actual_value;
    }
  
    msg << "\nExpected: " << expected_expression;
    if (ignoring_case) {
      msg << " (ignoring case)";
    }
    if (expected_value != expected_expression) {
      msg << "\nWhich is: " << expected_value;
    }
  
    return AssertionFailure(msg);
  }
  
  
  // Helper function for implementing ASSERT_NEAR.
  AssertionResult DoubleNearPredFormat(const char* expr1,
                                       const char* expr2,
                                       const char* abs_error_expr,
                                       double val1,
                                       double val2,
                                       double abs_error) {
    const double diff = fabs(val1 - val2);
    if (diff <= abs_error) return AssertionSuccess();
  
    // TODO(wan): do not print the value of an expression if it's
    // already a literal.
    Message msg;
    msg << "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 << ".";
    return AssertionFailure(msg);
  }
  
  
  // 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.
  
    StrStream val1_ss;
    val1_ss << std::setprecision(std::numeric_limits<RawType>::digits10 + 2)
            << val1;
  
    StrStream val2_ss;
    val2_ss << std::setprecision(std::numeric_limits<RawType>::digits10 + 2)
            << val2;
  
    Message msg;
    msg << "Expected: (" << expr1 << ") <= (" << expr2 << ")\n"
        << "  Actual: " << StrStreamToString(&val1_ss) << " vs "
        << StrStreamToString(&val2_ss);
  
    return AssertionFailure(msg);
  }
  
  }  // namespace internal
  
  // Asserts that val1 is less than, or almost equal to, val2.  Fails
  // otherwise.  In particular, it fails if either val1 or val2 is NaN.
  AssertionResult FloatLE(const char* expr1, const char* expr2,
                          float val1, float val2) {
    return internal::FloatingPointLE<float>(expr1, expr2, val1, val2);
  }
  
  // Asserts that val1 is less than, or almost equal to, val2.  Fails
  // otherwise.  In particular, it fails if either val1 or val2 is NaN.
  AssertionResult DoubleLE(const char* expr1, const char* expr2,
                           double val1, double val2) {
    return internal::FloatingPointLE<double>(expr1, expr2, val1, val2);
  }
  
  namespace internal {
  
  // The helper function for {ASSERT|EXPECT}_EQ with int or enum
  // arguments.
  AssertionResult CmpHelperEQ(const char* expected_expression,
                              const char* actual_expression,
                              BiggestInt expected,
                              BiggestInt actual) {
    if (expected == actual) {
      return AssertionSuccess();
    }
  
    return EqFailure(expected_expression,
                     actual_expression,
                     FormatForComparisonFailureMessage(expected, actual),
                     FormatForComparisonFailureMessage(actual, expected),
                     false);
  }
  
  // A macro for implementing the helper functions needed to implement
  // ASSERT_?? and EXPECT_?? with integer or enum arguments.  It is here
  // just to avoid copy-and-paste of similar code.
  #define GTEST_IMPL_CMP_HELPER_(op_name, op)\
  AssertionResult CmpHelper##op_name(const char* expr1, const char* expr2, \
                                     BiggestInt val1, BiggestInt val2) {\
    if (val1 op val2) {\
      return AssertionSuccess();\
    } else {\
      Message msg;\
      msg << "Expected: (" << expr1 << ") " #op " (" << expr2\
          << "), actual: " << FormatForComparisonFailureMessage(val1, val2)\
          << " vs " << FormatForComparisonFailureMessage(val2, val1);\
      return AssertionFailure(msg);\
    }\
  }
  
  // Implements the helper function for {ASSERT|EXPECT}_NE with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(NE, !=)
  // Implements the helper function for {ASSERT|EXPECT}_LE with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(LE, <=)
  // Implements the helper function for {ASSERT|EXPECT}_LT with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(LT, < )
  // Implements the helper function for {ASSERT|EXPECT}_GE with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(GE, >=)
  // Implements the helper function for {ASSERT|EXPECT}_GT with int or
  // enum arguments.
  GTEST_IMPL_CMP_HELPER_(GT, > )
  
  #undef GTEST_IMPL_CMP_HELPER_
  
  // The helper function for {ASSERT|EXPECT}_STREQ.
  AssertionResult CmpHelperSTREQ(const char* expected_expression,
                                 const char* actual_expression,
                                 const char* expected,
                                 const char* actual) {
    if (String::CStringEquals(expected, actual)) {
      return AssertionSuccess();
    }
  
    return EqFailure(expected_expression,
                     actual_expression,
                     String::ShowCStringQuoted(expected),
                     String::ShowCStringQuoted(actual),
                     false);
  }
  
  // The helper function for {ASSERT|EXPECT}_STRCASEEQ.
  AssertionResult CmpHelperSTRCASEEQ(const char* expected_expression,
                                     const char* actual_expression,
                                     const char* expected,
                                     const char* actual) {
    if (String::CaseInsensitiveCStringEquals(expected, actual)) {
      return AssertionSuccess();
    }
  
    return EqFailure(expected_expression,
                     actual_expression,
                     String::ShowCStringQuoted(expected),
                     String::ShowCStringQuoted(actual),
                     true);
  }
  
  // The helper function for {ASSERT|EXPECT}_STRNE.
  AssertionResult CmpHelperSTRNE(const char* s1_expression,
                                 const char* s2_expression,
                                 const char* s1,
                                 const char* s2) {
    if (!String::CStringEquals(s1, s2)) {
      return AssertionSuccess();
    } else {
      Message msg;
      msg << "Expected: (" << s1_expression << ") != ("
          << s2_expression << "), actual: \""
          << s1 << "\" vs \"" << s2 << "\"";
      return AssertionFailure(msg);
    }
  }
  
  // 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 {
      Message msg;
      msg << "Expected: (" << s1_expression << ") != ("
          << s2_expression << ") (ignoring case), actual: \""
          << s1 << "\" vs \"" << s2 << "\"";
      return AssertionFailure(msg);
    }
  }
  
  }  // 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(
        Message()
        << "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);
  }
  
  #if GTEST_HAS_STD_STRING
  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);
  }
  #endif  // GTEST_HAS_STD_STRING
  
  #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;  // String::Format can't exceed this length.
    // 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 String error_hex(String::Format("0x%08X ", hr));
    Message msg;
    msg << "Expected: " << expr << " " << expected << ".\n"
        << "  Actual: " << error_hex << error_text << "\n";
  
    return ::testing::AssertionFailure(msg);
  }
  
  }  // 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.
  // The output buffer str must containt at least 32 characters.
  // The function returns the address of the output buffer.
  // 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 output
  // as '(Invalid Unicode 0xXXXXXXXX)'.
  char* CodePointToUtf8(UInt32 code_point, char* str) {
    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 if (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
    } else {
      // The longest string String::Format can produce when invoked
      // with these parameters is 28 character long (not including
      // the terminating nul character). We are asking for 32 character
      // buffer just in case. This is also enough for strncpy to
      // null-terminate the destination string.
      posix::StrNCpy(
          str, String::Format("(Invalid Unicode 0x%X)", code_point).c_str(), 32);
      str[31] = '\0';  // Makes sure no change in the format to strncpy leaves
                       // the result unterminated.
    }
    return str;
  }
  
  // The following two functions only make sense if the the system
  // uses UTF-16 for wide string encoding. All supported systems
  // with 16 bit wchar_t (Windows, Cygwin, Symbian OS) do use UTF-16.
  
  // Determines if the arguments constitute UTF-16 surrogate pair
  // and thus should be combined into a single Unicode code point
  // using CreateCodePointFromUtf16SurrogatePair.
  inline bool IsUtf16SurrogatePair(wchar_t first, wchar_t second) {
    return sizeof(wchar_t) == 2 &&
        (first & 0xFC00) == 0xD800 && (second & 0xFC00) == 0xDC00;
  }
  
  // Creates a Unicode code point from UTF16 surrogate pair.
  inline UInt32 CreateCodePointFromUtf16SurrogatePair(wchar_t first,
                                                      wchar_t second) {
    const UInt32 mask = (1 << 10) - 1;
    return (sizeof(wchar_t) == 2) ?
        (((first & mask) << 10) | (second & mask)) + 0x10000 :
        // This function should not be called when the condition is
        // false, but we provide a sensible default in case it is.
        static_cast<UInt32>(first);
  }
  
  // Converts a wide string to a narrow string in UTF-8 encoding.
  // The wide string is assumed to have the following encoding:
  //   UTF-16 if sizeof(wchar_t) == 2 (on Windows, Cygwin, Symbian OS)
  //   UTF-32 if sizeof(wchar_t) == 4 (on Linux)
  // Parameter str points to a null-terminated wide string.
  // Parameter num_chars may additionally limit the number
  // of wchar_t characters processed. -1 is used when the entire string
  // should be processed.
  // If the string contains code points that are not valid Unicode code points
  // (i.e. outside of Unicode range U+0 to U+10FFFF) they will be output
  // as '(Invalid Unicode 0xXXXXXXXX)'. If the string is in UTF16 encoding
  // and contains invalid UTF-16 surrogate pairs, values in those pairs
  // will be encoded as individual Unicode characters from Basic Normal Plane.
  String WideStringToUtf8(const wchar_t* str, int num_chars) {
    if (num_chars == -1)
      num_chars = static_cast<int>(wcslen(str));
  
    StrStream 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]);
      }
  
      char buffer[32];  // CodePointToUtf8 requires a buffer this big.
      stream << CodePointToUtf8(unicode_code_point, buffer);
    }
    return StrStreamToString(&stream);
  }
  
  // Converts a wide C string to a String using the UTF-8 encoding.
  // NULL will be converted to "(null)".
  String String::ShowWideCString(const wchar_t * wide_c_str) {
    if (wide_c_str == NULL) return String("(null)");
  
    return String(internal::WideStringToUtf8(wide_c_str, -1).c_str());
  }
  
  // Similar to ShowWideCString(), except that this function encloses
  // the converted string in double quotes.
  String String::ShowWideCStringQuoted(const wchar_t* wide_c_str) {
    if (wide_c_str == NULL) return String("(null)");
  
    return String::Format("L\"%s\"",
                          String::ShowWideCString(wide_c_str).c_str());
  }
  
  // Compares two wide C strings.  Returns true iff they have the same
  // content.
  //
  // Unlike wcscmp(), this function can handle NULL argument(s).  A NULL
  // C string is considered different to any non-NULL C string,
  // including the empty string.
  bool String::WideCStringEquals(const wchar_t * lhs, const wchar_t * rhs) {
    if (lhs == NULL) return rhs == NULL;
  
    if (rhs == NULL) return false;
  
    return wcscmp(lhs, rhs) == 0;
  }
  
  // Helper function for *_STREQ on wide strings.
  AssertionResult CmpHelperSTREQ(const char* expected_expression,
                                 const char* actual_expression,
                                 const wchar_t* expected,
                                 const wchar_t* actual) {
    if (String::WideCStringEquals(expected, actual)) {
      return AssertionSuccess();
    }
  
    return EqFailure(expected_expression,
                     actual_expression,
                     String::ShowWideCStringQuoted(expected),
                     String::ShowWideCStringQuoted(actual),
                     false);
  }
  
  // Helper function for *_STRNE on wide strings.
  AssertionResult CmpHelperSTRNE(const char* s1_expression,
                                 const char* s2_expression,
                                 const wchar_t* s1,
                                 const wchar_t* s2) {
    if (!String::WideCStringEquals(s1, s2)) {
      return AssertionSuccess();
    }
  
    Message msg;
    msg << "Expected: (" << s1_expression << ") != ("
        << s2_expression << "), actual: "
        << String::ShowWideCStringQuoted(s1)
        << " vs " << String::ShowWideCStringQuoted(s2);
    return AssertionFailure(msg);
  }
  
  // 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
    return wcscasecmp(lhs, rhs) == 0;
  #else
    // 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
  }
  
  // Compares this with another String.
  // Returns < 0 if this is less than rhs, 0 if this is equal to rhs, or > 0
  // if this is greater than rhs.
  int String::Compare(const String & rhs) const {
    const char* const lhs_c_str = c_str();
    const char* const rhs_c_str = rhs.c_str();
  
    if (lhs_c_str == NULL) {
      return rhs_c_str == NULL ? 0 : -1;  // NULL < anything except NULL
    } else if (rhs_c_str == NULL) {
      return 1;
    }
  
    const size_t shorter_str_len =
        length() <= rhs.length() ? length() : rhs.length();
    for (size_t i = 0; i != shorter_str_len; i++) {
      if (lhs_c_str[i] < rhs_c_str[i]) {
        return -1;
      } else if (lhs_c_str[i] > rhs_c_str[i]) {
        return 1;
      }
    }
    return (length() < rhs.length()) ? -1 :
        (length() > rhs.length()) ? 1 : 0;
  }
  
  // Returns true iff this String ends with the given suffix.  *Any*
  // String is considered to end with a NULL or empty suffix.
  bool String::EndsWith(const char* suffix) const {
    if (suffix == NULL || CStringEquals(suffix, "")) return true;
  
    if (c_str() == NULL) return false;
  
    const size_t this_len = strlen(c_str());
    const size_t suffix_len = strlen(suffix);
    return (this_len >= suffix_len) &&
           CStringEquals(c_str() + this_len - suffix_len, suffix);
  }
  
  // Returns true iff this String ends with the given suffix, ignoring case.
  // Any String is considered to end with a NULL or empty suffix.
  bool String::EndsWithCaseInsensitive(const char* suffix) const {
    if (suffix == NULL || CStringEquals(suffix, "")) return true;
  
    if (c_str() == NULL) return false;
  
    const size_t this_len = strlen(c_str());
    const size_t suffix_len = strlen(suffix);
    return (this_len >= suffix_len) &&
           CaseInsensitiveCStringEquals(c_str() + this_len - suffix_len, suffix);
  }
  
  // Formats a list of arguments to a String, using the same format
  // spec string as for printf.
  //
  // We do not use the StringPrintf class as it is not universally
  // available.
  //
  // The result is limited to 4096 characters (including the tailing 0).
  // If 4096 characters are not enough to format the input, or if
  // there's an error, "<formatting error or buffer exceeded>" is
  // returned.
  String String::Format(const char * format, ...) {
    va_list args;
    va_start(args, format);
  
    char buffer[4096];
    const int kBufferSize = sizeof(buffer)/sizeof(buffer[0]);
  
    // MSVC 8 deprecates vsnprintf(), so we want to suppress warning
    // 4996 (deprecated function) there.
  #ifdef _MSC_VER  // We are using MSVC.
  #pragma warning(push)          // Saves the current warning state.
  #pragma warning(disable:4996)  // Temporarily disables warning 4996.
    const int size = vsnprintf(buffer, kBufferSize, format, args);
  #pragma warning(pop)           // Restores the warning state.
  #else  // We are not using MSVC.
    const int size = vsnprintf(buffer, kBufferSize, format, args);
  #endif  // _MSC_VER
    va_end(args);
  
    // vsnprintf()'s behavior is not portable.  When the buffer is not
    // big enough, it returns a negative value in MSVC, and returns the
    // needed buffer size on Linux.  When there is an output error, it
    // always returns a negative value.  For simplicity, we lump the two
    // error cases together.
    if (size < 0 || size >= kBufferSize) {
      return String("<formatting error or buffer exceeded>");
    } else {
      return String(buffer, size);
    }
  }
  
  // Converts the buffer in a StrStream to a String, converting NUL
  // bytes to "\\0" along the way.
  String StrStreamToString(StrStream* ss) {
  #if GTEST_HAS_STD_STRING
    const ::std::string& str = ss->str();
    const char* const start = str.c_str();
    const char* const end = start + str.length();
  #else
    const char* const start = ss->str();
    const char* const end = start + ss->pcount();
  #endif  // GTEST_HAS_STD_STRING
  
    // We need to use a helper StrStream to do this transformation
    // because String doesn't support push_back().
    StrStream helper;
    for (const char* ch = start; ch != end; ++ch) {
      if (*ch == '\0') {
        helper << "\\0";  // Replaces NUL with "\\0";
      } else {
        helper.put(*ch);
      }
    }
  
  #if GTEST_HAS_STD_STRING
    return String(helper.str().c_str());
  #else
    const String str(helper.str(), helper.pcount());
    helper.freeze(false);
    ss->freeze(false);
    return str;
  #endif  // GTEST_HAS_STD_STRING
  }
  
  // Appends the user-supplied message to the Google-Test-generated message.
  String AppendUserMessage(const String& gtest_msg,
                           const Message& user_msg) {
    // Appends the user message if it's non-empty.
    const String user_msg_string = user_msg.GetString();
    if (user_msg_string.empty()) {
      return gtest_msg;
    }
  
    Message msg;
    msg << gtest_msg << "\n" << user_msg_string;
  
    return msg.GetString();
  }
  
  }  // namespace internal
  
  // class TestResult
  
  // Creates an empty TestResult.
  TestResult::TestResult()
      : test_part_results_(new internal::Vector<TestPartResult>),
        test_properties_(new internal::Vector<TestProperty>),
        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 {
    return test_part_results_->GetElement(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 {
    return test_properties_->GetElement(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_->PushBack(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 TestProperty& test_property) {
    if (!ValidateTestProperty(test_property)) {
      return;
    }
    internal::MutexLock lock(&test_properites_mutex_);
    TestProperty* const property_with_matching_key =
        test_properties_->FindIf(
            internal::TestPropertyKeyIs(test_property.key()));
    if (property_with_matching_key == NULL) {
      test_properties_->PushBack(test_property);
      return;
    }
    property_with_matching_key->SetValue(test_property.value());
  }
  
  // Adds a failure if the key is a reserved attribute of Google Test
  // testcase tags.  Returns true if the property is valid.
  bool TestResult::ValidateTestProperty(const TestProperty& test_property) {
    internal::String key(test_property.key());
    if (key == "name" || key == "status" || key == "time" || key == "classname") {
      ADD_FAILURE()
          << "Reserved key used in RecordProperty(): "
          << key
          << " ('name', 'status', 'time', and 'classname' are reserved by "
          << GTEST_NAME_ << ")";
      return false;
    }
    return true;
  }
  
  // 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 test_part_results_->CountIf(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 test_part_results_->CountIf(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 test_part_results_->size();
  }
  
  // Returns the number of the test properties.
  int TestResult::test_property_count() const {
    return test_properties_->size();
  }
  
  // class Test
  
  // Creates a Test object.
  
  // The c'tor saves the values of all Google Test flags.
  Test::Test()
      : gtest_flag_saver_(new internal::GTestFlagSaver) {
  }
  
  // The d'tor restores the values of all Google Test flags.
  Test::~Test() {
    delete gtest_flag_saver_;
  }
  
  // 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 char* key, const char* value) {
    UnitTest::GetInstance()->RecordPropertyForCurrentTest(key, value);
  }
  
  // Allows user supplied key value pairs to be recorded for later output.
  void Test::RecordProperty(const char* 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 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,
        String());  // No stack trace, either.
  }
  
  }  // namespace internal
  
  #if GTEST_OS_WINDOWS
  // We are on Windows.
  
  // Adds an "exception thrown" fatal failure to the current test.
  static void AddExceptionThrownFailure(DWORD exception_code,
                                        const char* location) {
    Message message;
    message << "Exception thrown with code 0x" << std::setbase(16) <<
      exception_code << std::setbase(10) << " in " << location << ".";
  
    internal::ReportFailureInUnknownLocation(TestPartResult::kFatalFailure,
                                             message.GetString());
  }
  
  #endif  // GTEST_OS_WINDOWS
  
  // Google Test requires all tests in the same test case to use the same test
  // fixture class.  This function checks if the current test has the
  // same fixture class as the first test in the current test case.  If
  // yes, it returns true; otherwise it generates a Google Test failure and
  // returns false.
  bool Test::HasSameFixtureClass() {
    internal::UnitTestImpl* const impl = internal::GetUnitTestImpl();
    const TestCase* const test_case = impl->current_test_case();
  
    // Info about the first test in the current test case.
    const internal::TestInfoImpl* const first_test_info =
        test_case->test_info_list().GetElement(0)->impl();
    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 internal::TestInfoImpl* const this_test_info =
        impl->current_test_info()->impl();
    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) {
        // The user mixed TEST and TEST_F in this test case - we'll tell
        // him/her how to fix it.
  
        // Gets the name of the TEST and the name of the TEST_F.  Note
        // that first_is_TEST and this_is_TEST cannot both be true, as
        // the fixture IDs are different for the two tests.
        const char* const TEST_name =
            first_is_TEST ? first_test_name : this_test_name;
        const char* const TEST_F_name =
            first_is_TEST ? this_test_name : first_test_name;
  
        ADD_FAILURE()
            << "All tests in the same test case must use the same test fixture\n"
            << "class, so mixing TEST_F and TEST in the same test case is\n"
            << "illegal.  In test case " << this_test_info->test_case_name()
            << ",\n"
            << "test " << TEST_F_name << " is defined using TEST_F but\n"
            << "test " << TEST_name << " is defined using TEST.  You probably\n"
            << "want to change the TEST to TEST_F or move it to another test\n"
            << "case.";
      } else {
        // The user defined two fixture classes with the same name in
        // two namespaces - we'll tell him/her how to fix it.
        ADD_FAILURE()
            << "All tests in the same test case must use the same test fixture\n"
            << "class.  However, in test case "
            << this_test_info->test_case_name() << ",\n"
            << "you defined test " << first_test_name
            << " and test " << this_test_name << "\n"
            << "using two different test fixture classes.  This can happen if\n"
            << "the two classes are from different namespaces or translation\n"
            << "units and have the same name.  You should probably rename one\n"
            << "of the classes to put the tests into different test cases.";
      }
      return false;
    }
  
    return true;
  }
  
  // Runs the test and updates the test result.
  void Test::Run() {
    if (!HasSameFixtureClass()) return;
  
    internal::UnitTestImpl* const impl = internal::GetUnitTestImpl();
  #if GTEST_HAS_SEH
    // Catch SEH-style exceptions.
    impl->os_stack_trace_getter()->UponLeavingGTest();
    __try {
      SetUp();
    } __except(internal::UnitTestOptions::GTestShouldProcessSEH(
        GetExceptionCode())) {
      AddExceptionThrownFailure(GetExceptionCode(), "SetUp()");
    }
  
    // We will run the test only if SetUp() had no fatal failure.
    if (!HasFatalFailure()) {
      impl->os_stack_trace_getter()->UponLeavingGTest();
      __try {
        TestBody();
      } __except(internal::UnitTestOptions::GTestShouldProcessSEH(
          GetExceptionCode())) {
        AddExceptionThrownFailure(GetExceptionCode(), "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();
    __try {
      TearDown();
    } __except(internal::UnitTestOptions::GTestShouldProcessSEH(
        GetExceptionCode())) {
      AddExceptionThrownFailure(GetExceptionCode(), "TearDown()");
    }
  
  #else  // We are on a compiler or platform that doesn't support SEH.
    impl->os_stack_trace_getter()->UponLeavingGTest();
    SetUp();
  
    // We will run the test only if SetUp() was successful.
    if (!HasFatalFailure()) {
      impl->os_stack_trace_getter()->UponLeavingGTest();
      TestBody();
    }
  
    // 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();
    TearDown();
  #endif  // GTEST_HAS_SEH
  }
  
  
  // 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 via impl_.
  TestInfo::TestInfo(const char* test_case_name,
                     const char* name,
                     const char* test_case_comment,
                     const char* comment,
                     internal::TypeId fixture_class_id,
                     internal::TestFactoryBase* factory) {
    impl_ = new internal::TestInfoImpl(this, test_case_name, name,
                                       test_case_comment, comment,
                                       fixture_class_id, factory);
  }
  
  // Destructs a TestInfo object.
  TestInfo::~TestInfo() {
    delete impl_;
  }
  
  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
  //   test_case_comment: a comment on the test case that will be included in
  //                      the test output
  //   comment:          a comment on the test that will be included in the
  //                     test output
  //   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* test_case_comment, const char* comment,
      TypeId fixture_class_id,
      SetUpTestCaseFunc set_up_tc,
      TearDownTestCaseFunc tear_down_tc,
      TestFactoryBase* factory) {
    TestInfo* const test_info =
        new TestInfo(test_case_name, name, test_case_comment, comment,
                     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,
                                 const char* file, int line) {
    Message errors;
    errors
        << "Attempted redefinition of test case " << test_case_name << ".\n"
        << "All tests in the same test case must use the same test fixture\n"
        << "class.  However, in test case " << test_case_name << ", you tried\n"
        << "to define a test using a fixture class different from the one\n"
        << "used earlier. This can happen if the two fixture classes are\n"
        << "from different namespaces and have the same name. You should\n"
        << "probably rename one of the classes to put the tests into different\n"
        << "test cases.";
  
    fprintf(stderr, "%s %s", FormatFileLocation(file, line).c_str(),
            errors.GetString().c_str());
  }
  #endif  // GTEST_HAS_PARAM_TEST
  
  }  // namespace internal
  
  // Returns the test case name.
  const char* TestInfo::test_case_name() const {
    return impl_->test_case_name();
  }
  
  // Returns the test name.
  const char* TestInfo::name() const {
    return impl_->name();
  }
  
  // Returns the test case comment.
  const char* TestInfo::test_case_comment() const {
    return impl_->test_case_comment();
  }
  
  // Returns the test comment.
  const char* TestInfo::comment() const {
    return impl_->comment();
  }
  
  // Returns true if this test should run.
  bool TestInfo::should_run() const { return impl_->should_run(); }
  
  // Returns true if this test matches the user-specified filter.
  bool TestInfo::matches_filter() const { return impl_->matches_filter(); }
  
  // Returns the result of the test.
  const TestResult* TestInfo::result() const { return impl_->result(); }
  
  // Increments the number of death tests encountered in this test so
  // far.
  int TestInfo::increment_death_test_count() {
    return impl_->result()->increment_death_test_count();
  }
  
  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 && internal::String(test_info->name()).Compare(name_) == 0;
    }
  
   private:
    internal::String name_;
  };
  
  }  // namespace
  
  namespace internal {
  
  // This method expands all parameterized tests registered with macros TEST_P
  // and INSTANTIATE_TEST_CASE_P into regular tests and registers those.
  // This will be done just once during the program runtime.
  void UnitTestImpl::RegisterParameterizedTests() {
  #if GTEST_HAS_PARAM_TEST
    if (!parameterized_tests_registered_) {
      parameterized_test_registry_.RegisterTests();
      parameterized_tests_registered_ = true;
    }
  #endif
  }
  
  // Creates the test object, runs it, records its result, and then
  // deletes it.
  void TestInfoImpl::Run() {
    if (!should_run_) return;
  
    // Tells UnitTest where to store test result.
    UnitTestImpl* const impl = internal::GetUnitTestImpl();
    impl->set_current_test_info(parent_);
  
    TestEventListener* repeater = UnitTest::GetInstance()->listeners().repeater();
  
    // Notifies the unit test event listeners that a test is about to start.
    repeater->OnTestStart(*parent_);
  
    const TimeInMillis start = GetTimeInMillis();
  
    impl->os_stack_trace_getter()->UponLeavingGTest();
  #if GTEST_HAS_SEH
    // Catch SEH-style exceptions.
    Test* test = NULL;
  
    __try {
      // Creates the test object.
      test = factory_->CreateTest();
    } __except(internal::UnitTestOptions::GTestShouldProcessSEH(
        GetExceptionCode())) {
      AddExceptionThrownFailure(GetExceptionCode(),
                                "the test fixture's constructor");
      return;
    }
  #else  // We are on a compiler or platform that doesn't support SEH.
  
    // TODO(wan): If test->Run() throws, test won't be deleted.  This is
    // not a problem now as we don't use exceptions.  If we were to
    // enable exceptions, we should revise the following to be
    // exception-safe.
  
    // Creates the test object.
    Test* test = factory_->CreateTest();
  #endif  // GTEST_HAS_SEH
  
    // Runs the test only if the constructor of the test fixture didn't
    // generate a fatal failure.
    if (!Test::HasFatalFailure()) {
      test->Run();
    }
  
    // Deletes the test object.
    impl->os_stack_trace_getter()->UponLeavingGTest();
    delete test;
    test = NULL;
  
    result_.set_elapsed_time(GetTimeInMillis() - start);
  
    // Notifies the unit test event listener that a test has just finished.
    repeater->OnTestEnd(*parent_);
  
    // Tells UnitTest to stop associating assertion results to this
    // test.
    impl->set_current_test_info(NULL);
  }
  
  }  // namespace internal
  
  // class TestCase
  
  // Gets the number of successful tests in this test case.
  int TestCase::successful_test_count() const {
    return test_info_list_->CountIf(TestPassed);
  }
  
  // Gets the number of failed tests in this test case.
  int TestCase::failed_test_count() const {
    return test_info_list_->CountIf(TestFailed);
  }
  
  int TestCase::disabled_test_count() const {
    return test_info_list_->CountIf(TestDisabled);
  }
  
  // Get the number of tests in this test case that should run.
  int TestCase::test_to_run_count() const {
    return test_info_list_->CountIf(ShouldRunTest);
  }
  
  // Gets the number of all tests.
  int TestCase::total_test_count() const {
    return test_info_list_->size();
  }
  
  // Creates a TestCase with the given name.
  //
  // Arguments:
  //
  //   name:         name of the 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* name, const char* comment,
                     Test::SetUpTestCaseFunc set_up_tc,
                     Test::TearDownTestCaseFunc tear_down_tc)
      : name_(name),
        comment_(comment),
        test_info_list_(new internal::Vector<TestInfo*>),
        test_indices_(new internal::Vector<int>),
        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.
    test_info_list_->ForEach(internal::Delete<TestInfo>);
  }
  
  // Returns the i-th test among all the tests. i can range from 0 to
  // total_test_count() - 1. If i is not in that range, returns NULL.
  const TestInfo* TestCase::GetTestInfo(int i) const {
    const int index = test_indices_->GetElementOr(i, -1);
    return index < 0 ? NULL : test_info_list_->GetElement(index);
  }
  
  // Returns the i-th test among all the tests. i can range from 0 to
  // total_test_count() - 1. If i is not in that range, returns NULL.
  TestInfo* TestCase::GetMutableTestInfo(int i) {
    const int index = test_indices_->GetElementOr(i, -1);
    return index < 0 ? NULL : test_info_list_->GetElement(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_->PushBack(test_info);
    test_indices_->PushBack(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();
    set_up_tc_();
  
    const internal::TimeInMillis start = internal::GetTimeInMillis();
    for (int i = 0; i < total_test_count(); i++) {
      GetMutableTestInfo(i)->impl()->Run();
    }
    elapsed_time_ = internal::GetTimeInMillis() - start;
  
    impl->os_stack_trace_getter()->UponLeavingGTest();
    tear_down_tc_();
    repeater->OnTestCaseEnd(*this);
    impl->set_current_test_case(NULL);
  }
  
  // Clears the results of all tests in this test case.
  void TestCase::ClearResult() {
    test_info_list_->ForEach(internal::TestInfoImpl::ClearTestResult);
  }
  
  // Returns true iff test passed.
  bool TestCase::TestPassed(const TestInfo * test_info) {
    const internal::TestInfoImpl* const impl = test_info->impl();
    return impl->should_run() && impl->result()->Passed();
  }
  
  // Returns true iff test failed.
  bool TestCase::TestFailed(const TestInfo * test_info) {
    const internal::TestInfoImpl* const impl = test_info->impl();
    return impl->should_run() && impl->result()->Failed();
  }
  
  // Returns true iff test is disabled.
  bool TestCase::TestDisabled(const TestInfo * test_info) {
    return test_info->impl()->is_disabled();
  }
  
  // Returns true if the given test should run.
  bool TestCase::ShouldRunTest(const TestInfo *test_info) {
    return test_info->impl()->should_run();
  }
  
  // Shuffles the tests in this test case.
  void TestCase::ShuffleTests(internal::Random* random) {
    test_indices_->Shuffle(random);
  }
  
  // Restores the test order to before the first shuffle.
  void TestCase::UnshuffleTests() {
    for (int i = 0; i < test_indices_->size(); i++) {
      test_indices_->GetMutableElement(i) = 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 internal::String FormatCountableNoun(int count,
                                              const char * singular_form,
                                              const char * plural_form) {
    return internal::String::Format("%d %s", count,
                                    count == 1 ? singular_form : plural_form);
  }
  
  // Formats the count of tests.
  static internal::String FormatTestCount(int test_count) {
    return FormatCountableNoun(test_count, "test", "tests");
  }
  
  // Formats the count of test cases.
  static internal::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
    }
  
    return "Unknown result type";
  }
  
  // Prints a TestPartResult to a String.
  static internal::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 internal::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
  
  namespace internal {
  
  enum GTestColor {
    COLOR_DEFAULT,
    COLOR_RED,
    COLOR_GREEN,
    COLOR_YELLOW
  };
  
  #if GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE
  
  // Returns the character attribute for the given color.
  WORD GetColorAttribute(GTestColor color) {
    switch (color) {
      case COLOR_RED:    return FOREGROUND_RED;
      case COLOR_GREEN:  return FOREGROUND_GREEN;
      case COLOR_YELLOW: return FOREGROUND_RED | FOREGROUND_GREEN;
      default:           return 0;
    }
  }
  
  #else
  
  // Returns the ANSI color code for the given color.  COLOR_DEFAULT is
  // an invalid input.
  const char* GetAnsiColorCode(GTestColor color) {
    switch (color) {
      case COLOR_RED:     return "1";
      case COLOR_GREEN:   return "2";
      case COLOR_YELLOW:  return "3";
      default:            return NULL;
    };
  }
  
  #endif  // GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE
  
  // Returns true iff Google Test should use colors in the output.
  bool ShouldUseColor(bool stdout_is_tty) {
    const char* const gtest_color = GTEST_FLAG(color).c_str();
  
    if (String::CaseInsensitiveCStringEquals(gtest_color, "auto")) {
  #if GTEST_OS_WINDOWS
      // On Windows the TERM variable is usually not set, but the
      // console there does support colors.
      return stdout_is_tty;
  #else
      // On non-Windows platforms, we rely on the TERM variable.
      const char* const term = posix::GetEnv("TERM");
      const bool term_supports_color =
          String::CStringEquals(term, "xterm") ||
          String::CStringEquals(term, "xterm-color") ||
          String::CStringEquals(term, "xterm-256color") ||
          String::CStringEquals(term, "linux") ||
          String::CStringEquals(term, "cygwin");
      return stdout_is_tty && term_supports_color;
  #endif  // GTEST_OS_WINDOWS
    }
  
    return String::CaseInsensitiveCStringEquals(gtest_color, "yes") ||
        String::CaseInsensitiveCStringEquals(gtest_color, "true") ||
        String::CaseInsensitiveCStringEquals(gtest_color, "t") ||
        String::CStringEquals(gtest_color, "1");
    // We take "yes", "true", "t", and "1" as meaning "yes".  If the
    // value is neither one of these nor "auto", we treat it as "no" to
    // be conservative.
  }
  
  // Helpers for printing colored strings to stdout. Note that on Windows, we
  // cannot simply emit special characters and have the terminal change colors.
  // This routine must actually emit the characters rather than return a string
  // that would be colored when printed, as can be done on Linux.
  void ColoredPrintf(GTestColor color, const char* fmt, ...) {
    va_list args;
    va_start(args, fmt);
  
  #if GTEST_OS_WINDOWS_MOBILE || GTEST_OS_SYMBIAN || GTEST_OS_ZOS
    const bool use_color = false;
  #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
    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;
  
    SetConsoleTextAttribute(stdout_handle,
                            GetColorAttribute(color) | FOREGROUND_INTENSITY);
    vprintf(fmt, args);
  
    // 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);
  }
  
  // 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);
  
    internal::String test_case_name_;
  };
  
    // Fired before each iteration of tests starts.
  void PrettyUnitTestResultPrinter::OnTestIterationStart(
      const UnitTest& unit_test, int iteration) {
    if (GTEST_FLAG(repeat) != 1)
      printf("\nRepeating all tests (iteration %d) . . .\n\n", iteration + 1);
  
    const char* const filter = GTEST_FLAG(filter).c_str();
  
    // Prints the filter if it's not *.  This reminds the user that some
    // tests may be skipped.
    if (!internal::String::CStringEquals(filter, kUniversalFilter)) {
      ColoredPrintf(COLOR_YELLOW,
                    "Note: %s filter = %s\n", GTEST_NAME_, filter);
    }
  
    if (internal::ShouldShard(kTestTotalShards, kTestShardIndex, false)) {
      ColoredPrintf(COLOR_YELLOW,
                    "Note: This is test shard %s of %s.\n",
                    internal::posix::GetEnv(kTestShardIndex),
                    internal::posix::GetEnv(kTestTotalShards));
    }
  
    if (GTEST_FLAG(shuffle)) {
      ColoredPrintf(COLOR_YELLOW,
                    "Note: Randomizing tests' orders with a seed of %d .\n",
                    unit_test.random_seed());
    }
  
    ColoredPrintf(COLOR_GREEN,  "[==========] ");
    printf("Running %s from %s.\n",
           FormatTestCount(unit_test.test_to_run_count()).c_str(),
           FormatTestCaseCount(unit_test.test_case_to_run_count()).c_str());
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnEnvironmentsSetUpStart(
      const UnitTest& /*unit_test*/) {
    ColoredPrintf(COLOR_GREEN,  "[----------] ");
    printf("Global test environment set-up.\n");
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnTestCaseStart(const TestCase& test_case) {
    test_case_name_ = test_case.name();
    const internal::String counts =
        FormatCountableNoun(test_case.test_to_run_count(), "test", "tests");
    ColoredPrintf(COLOR_GREEN, "[----------] ");
    printf("%s from %s", counts.c_str(), test_case_name_.c_str());
    if (test_case.comment()[0] == '\0') {
      printf("\n");
    } else {
      printf(", where %s\n", test_case.comment());
    }
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnTestStart(const TestInfo& test_info) {
    ColoredPrintf(COLOR_GREEN,  "[ RUN      ] ");
    PrintTestName(test_case_name_.c_str(), test_info.name());
    if (test_info.comment()[0] == '\0') {
      printf("\n");
    } else {
      printf(", where %s\n", test_info.comment());
    }
    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_case_name_.c_str(), test_info.name());
    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;
  
    test_case_name_ = test_case.name();
    const internal::String counts =
        FormatCountableNoun(test_case.test_to_run_count(), "test", "tests");
    ColoredPrintf(COLOR_GREEN, "[----------] ");
    printf("%s from %s (%s ms total)\n\n",
           counts.c_str(), test_case_name_.c_str(),
           internal::StreamableToString(test_case.elapsed_time()).c_str());
    fflush(stdout);
  }
  
  void PrettyUnitTestResultPrinter::OnEnvironmentsTearDownStart(
      const UnitTest& /*unit_test*/) {
    ColoredPrintf(COLOR_GREEN,  "[----------] ");
    printf("Global test environment tear-down\n");
    fflush(stdout);
  }
  
  // Internal helper for printing the list of failed tests.
  void PrettyUnitTestResultPrinter::PrintFailedTests(const UnitTest& unit_test) {
    const int failed_test_count = unit_test.failed_test_count();
    if (failed_test_count == 0) {
      return;
    }
  
    for (int i = 0; i < unit_test.total_test_case_count(); ++i) {
      const TestCase& test_case = *unit_test.GetTestCase(i);
      if (!test_case.should_run() || (test_case.failed_test_count() == 0)) {
        continue;
      }
      for (int j = 0; j < test_case.total_test_count(); ++j) {
        const TestInfo& test_info = *test_case.GetTestInfo(j);
        if (!test_info.should_run() || test_info.result()->Passed()) {
          continue;
        }
        ColoredPrintf(COLOR_RED, "[  FAILED  ] ");
        printf("%s.%s", test_case.name(), test_info.name());
        if (test_case.comment()[0] != '\0' ||
            test_info.comment()[0] != '\0') {
          printf(", where %s", test_case.comment());
          if (test_case.comment()[0] != '\0' &&
              test_info.comment()[0] != '\0') {
            printf(" and ");
          }
        }
        printf("%s\n", test_info.comment());
      }
    }
  }
  
   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.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.
    Vector<TestEventListener*> listeners_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(TestEventRepeater);
  };
  
  TestEventRepeater::~TestEventRepeater() {
    for (int i = 0; i < listeners_.size(); i++) {
      delete listeners_.GetElement(i);
    }
  }
  
  void TestEventRepeater::Append(TestEventListener *listener) {
    listeners_.PushBack(listener);
  }
  
  // TODO(vladl@google.com): Factor the search functionality into Vector::Find.
  TestEventListener* TestEventRepeater::Release(TestEventListener *listener) {
    for (int i = 0; i < listeners_.size(); ++i) {
      if (listeners_.GetElement(i) == listener) {
        listeners_.Erase(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 (int i = 0; i < listeners_.size(); i++) { \
        listeners_.GetElement(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_.GetElement(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 (int i = 0; i < listeners_.size(); i++) {
        listeners_.GetElement(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_.GetElement(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 String EscapeXml(const char* str, bool is_attribute);
  
    // Returns the given string with all characters invalid in XML removed.
    static String RemoveInvalidXmlCharacters(const char* str);
  
    // Convenience wrapper around EscapeXml when str is an attribute value.
    static String EscapeXmlAttribute(const char* str) {
      return EscapeXml(str, true);
    }
  
    // Convenience wrapper around EscapeXml when str is not an attribute value.
    static String EscapeXmlText(const char* str) { return EscapeXml(str, false); }
  
    // 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(FILE* out, const TestCase& test_case);
  
    // Prints an XML summary of unit_test to output stream out.
    static void PrintXmlUnitTest(FILE* out, 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 String is not empty, it includes a space at the beginning,
    // to delimit this attribute from prior attributes.
    static String TestPropertiesAsXmlAttributes(const TestResult& result);
  
    // The output file.
    const String output_file_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(XmlUnitTestResultPrinter);
  };
  
  // Creates a new XmlUnitTestResultPrinter.
  XmlUnitTestResultPrinter::XmlUnitTestResultPrinter(const char* output_file)
      : output_file_(output_file) {
    if (output_file_.c_str() == NULL || output_file_.empty()) {
      fprintf(stderr, "XML output file may not be null\n");
      fflush(stderr);
      exit(EXIT_FAILURE);
    }
  }
  
  // Called after the unit test ends.
  void XmlUnitTestResultPrinter::OnTestIterationEnd(const UnitTest& unit_test,
                                                    int /*iteration*/) {
    FILE* xmlout = NULL;
    FilePath output_file(output_file_);
    FilePath output_dir(output_file.RemoveFileName());
  
    if (output_dir.CreateDirectoriesRecursively()) {
      xmlout = posix::FOpen(output_file_.c_str(), "w");
    }
    if (xmlout == NULL) {
      // TODO(wan): report the reason of the failure.
      //
      // We don't do it for now as:
      //
      //   1. There is no urgent need for it.
      //   2. It's a bit involved to make the errno variable thread-safe on
      //      all three operating systems (Linux, Windows, and Mac OS).
      //   3. To interpret the meaning of errno in a thread-safe way,
      //      we need the strerror_r() function, which is not available on
      //      Windows.
      fprintf(stderr,
              "Unable to open file \"%s\"\n",
              output_file_.c_str());
      fflush(stderr);
      exit(EXIT_FAILURE);
    }
    PrintXmlUnitTest(xmlout, unit_test);
    fclose(xmlout);
  }
  
  // Returns an XML-escaped copy of the input string str.  If is_attribute
  // is true, the text is meant to appear as an attribute value, and
  // normalizable whitespace is preserved by replacing it with character
  // references.
  //
  // Invalid XML characters in str, if any, are stripped from the output.
  // It is expected that most, if not all, of the text processed by this
  // module will consist of ordinary English text.
  // If this module is ever modified to produce version 1.1 XML output,
  // most invalid characters can be retained using character references.
  // TODO(wan): It might be nice to have a minimally invasive, human-readable
  // escaping scheme for invalid characters, rather than dropping them.
  String XmlUnitTestResultPrinter::EscapeXml(const char* str, bool is_attribute) {
    Message m;
  
    if (str != NULL) {
      for (const char* src = str; *src; ++src) {
        switch (*src) {
          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(*src)) {
              if (is_attribute && IsNormalizableWhitespace(*src))
                m << String::Format("&#x%02X;", unsigned(*src));
              else
                m << *src;
            }
            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 ?.
  String XmlUnitTestResultPrinter::RemoveInvalidXmlCharacters(const char* str) {
    char* const output = new char[strlen(str) + 1];
    char* appender = output;
    for (char ch = *str; ch != '\0'; ch = *++str)
      if (IsValidXmlCharacter(ch))
        *appender++ = ch;
    *appender = '\0';
  
    String ret_value(output);
    delete[] output;
    return ret_value;
  }
  
  // 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.  The returned
  // C-string is owned by this function and cannot be released by the
  // caller.  Calling the function again invalidates the previous
  // result.
  const char* FormatTimeInMillisAsSeconds(TimeInMillis ms) {
    static String str;
    str = (Message() << (ms/1000.0)).GetString();
    return str.c_str();
  }
  
  // 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, next_segment - segment);
        *stream << "]]>]]&gt;<![CDATA[";
        segment = next_segment + strlen("]]>");
      } else {
        *stream << segment;
        break;
      }
    }
    *stream << "]]>";
  }
  
  // Prints an XML representation of a TestInfo object.
  // TODO(wan): There is also value in printing properties with the plain printer.
  void XmlUnitTestResultPrinter::OutputXmlTestInfo(::std::ostream* stream,
                                                   const char* test_case_name,
                                                   const TestInfo& test_info) {
    const TestResult& result = *test_info.result();
    *stream << "    <testcase name=\""
            << EscapeXmlAttribute(test_info.name()).c_str()
            << "\" status=\""
            << (test_info.should_run() ? "run" : "notrun")
            << "\" time=\""
            << FormatTimeInMillisAsSeconds(result.elapsed_time())
            << "\" classname=\"" << EscapeXmlAttribute(test_case_name).c_str()
            << "\"" << TestPropertiesAsXmlAttributes(result).c_str();
  
    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";
        *stream << "      <failure message=\""
                << EscapeXmlAttribute(part.summary()).c_str()
                << "\" type=\"\">";
        const String message = RemoveInvalidXmlCharacters(String::Format(
            "%s:%d\n%s",
            part.file_name(), part.line_number(),
            part.message()).c_str());
        OutputXmlCDataSection(stream, message.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(FILE* out,
                                                  const TestCase& test_case) {
    fprintf(out,
            "  <testsuite name=\"%s\" tests=\"%d\" failures=\"%d\" "
            "disabled=\"%d\" ",
            EscapeXmlAttribute(test_case.name()).c_str(),
            test_case.total_test_count(),
            test_case.failed_test_count(),
            test_case.disabled_test_count());
    fprintf(out,
            "errors=\"0\" time=\"%s\">\n",
            FormatTimeInMillisAsSeconds(test_case.elapsed_time()));
    for (int i = 0; i < test_case.total_test_count(); ++i) {
      StrStream stream;
      OutputXmlTestInfo(&stream, test_case.name(), *test_case.GetTestInfo(i));
      fprintf(out, "%s", StrStreamToString(&stream).c_str());
    }
    fprintf(out, "  </testsuite>\n");
  }
  
  // Prints an XML summary of unit_test to output stream out.
  void XmlUnitTestResultPrinter::PrintXmlUnitTest(FILE* out,
                                                  const UnitTest& unit_test) {
    fprintf(out, "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
    fprintf(out,
            "<testsuites tests=\"%d\" failures=\"%d\" disabled=\"%d\" "
            "errors=\"0\" time=\"%s\" ",
            unit_test.total_test_count(),
            unit_test.failed_test_count(),
            unit_test.disabled_test_count(),
            FormatTimeInMillisAsSeconds(unit_test.elapsed_time()));
    if (GTEST_FLAG(shuffle)) {
      fprintf(out, "random_seed=\"%d\" ", unit_test.random_seed());
    }
    fprintf(out, "name=\"AllTests\">\n");
    for (int i = 0; i < unit_test.total_test_case_count(); ++i)
      PrintXmlTestCase(out, *unit_test.GetTestCase(i));
    fprintf(out, "</testsuites>\n");
  }
  
  // Produces a string representing the test properties in a result as space
  // delimited XML attributes based on the property key="value" pairs.
  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
  
  // Class ScopedTrace
  
  // Pushes the given source file location and message onto a per-thread
  // trace stack maintained by Google Test.
  // L < UnitTest::mutex_
  ScopedTrace::ScopedTrace(const char* file, int line, const Message& message) {
    TraceInfo trace;
    trace.file = file;
    trace.line = line;
    trace.message = message.GetString();
  
    UnitTest::GetInstance()->PushGTestTrace(trace);
  }
  
  // Pops the info pushed by the c'tor.
  // L < UnitTest::mutex_
  ScopedTrace::~ScopedTrace() {
    UnitTest::GetInstance()->PopGTestTrace();
  }
  
  
  // class OsStackTraceGetter
  
  // Returns the current OS stack trace as a String.  Parameters:
  //
  //   max_depth  - the maximum number of stack frames to be included
  //                in the trace.
  //   skip_count - the number of top frames to be skipped; doesn't count
  //                against max_depth.
  //
  // L < mutex_
  // We use "L < mutex_" to denote that the function may acquire mutex_.
  String OsStackTraceGetter::CurrentStackTrace(int, int) {
    return String("");
  }
  
  // L < mutex_
  void OsStackTraceGetter::UponLeavingGTest() {
  }
  
  const char* const
  OsStackTraceGetter::kElidedFramesMarker =
      "... " GTEST_NAME_ " internal frames ...";
  
  }  // namespace internal
  
  // class TestEventListeners
  
  TestEventListeners::TestEventListeners()
      : repeater_(new internal::TestEventRepeater()),
        default_result_printer_(NULL),
        default_xml_generator_(NULL) {
  }
  
  TestEventListeners::~TestEventListeners() { delete repeater_; }
  
  // Returns the standard listener responsible for the default console
  // output.  Can be removed from the listeners list to shut down default
  // console output.  Note that removing this object from the listener list
  // with Release transfers its ownership to the user.
  void TestEventListeners::Append(TestEventListener* listener) {
    repeater_->Append(listener);
  }
  
  // Removes the given event listener from the list and returns it.  It then
  // becomes the caller's responsibility to delete the listener. Returns
  // NULL if the listener is not found in the list.
  TestEventListener* TestEventListeners::Release(TestEventListener* listener) {
    if (listener == default_result_printer_)
      default_result_printer_ = NULL;
    else if (listener == default_xml_generator_)
      default_xml_generator_ = NULL;
    return repeater_->Release(listener);
  }
  
  // Returns repeater that broadcasts the TestEventListener events to all
  // subscribers.
  TestEventListener* TestEventListeners::repeater() { return repeater_; }
  
  // Sets the default_result_printer attribute to the provided listener.
  // The listener is also added to the listener list and previous
  // default_result_printer is removed from it and deleted. The listener can
  // also be NULL in which case it will not be added to the list. Does
  // nothing if the previous and the current listener objects are the same.
  void TestEventListeners::SetDefaultResultPrinter(TestEventListener* listener) {
    if (default_result_printer_ != listener) {
      // It is an error to pass this method a listener that is already in the
      // list.
      delete Release(default_result_printer_);
      default_result_printer_ = listener;
      if (listener != NULL)
        Append(listener);
    }
  }
  
  // Sets the default_xml_generator attribute to the provided listener.  The
  // listener is also added to the listener list and previous
  // default_xml_generator is removed from it and deleted. The listener can
  // also be NULL in which case it will not be added to the list. Does
  // nothing if the previous and the current listener objects are the same.
  void TestEventListeners::SetDefaultXmlGenerator(TestEventListener* listener) {
    if (default_xml_generator_ != listener) {
      // It is an error to pass this method a listener that is already in the
      // list.
      delete Release(default_xml_generator_);
      default_xml_generator_ = listener;
      if (listener != NULL)
        Append(listener);
    }
  }
  
  // Controls whether events will be forwarded by the repeater to the
  // listeners in the list.
  bool TestEventListeners::EventForwardingEnabled() const {
    return repeater_->forwarding_enabled();
  }
  
  void TestEventListeners::SuppressEventForwarding() {
    repeater_->set_forwarding_enabled(false);
  }
  
  // class UnitTest
  
  // Gets the singleton UnitTest object.  The first time this method is
  // called, a UnitTest object is constructed and returned.  Consecutive
  // calls will return the same object.
  //
  // We don't protect this under mutex_ as a user is not supposed to
  // call this before main() starts, from which point on the return
  // value will never change.
  UnitTest * UnitTest::GetInstance() {
    // When compiled with MSVC 7.1 in optimized mode, destroying the
    // UnitTest object upon exiting the program messes up the exit code,
    // causing successful tests to appear failed.  We have to use a
    // different implementation in this case to bypass the compiler bug.
    // This implementation makes the compiler happy, at the cost of
    // leaking the UnitTest object.
  
    // CodeGear C++Builder insists on a public destructor for the
    // default implementation.  Use this implementation to keep good OO
    // design with private destructor.
  
  #if (_MSC_VER == 1310 && !defined(_DEBUG)) || defined(__BORLANDC__)
    static UnitTest* const instance = new UnitTest;
    return instance;
  #else
    static UnitTest instance;
    return &instance;
  #endif  // (_MSC_VER == 1310 && !defined(_DEBUG)) || defined(__BORLANDC__)
  }
  
  // Gets the number of successful test cases.
  int UnitTest::successful_test_case_count() const {
    return impl()->successful_test_case_count();
  }
  
  // Gets the number of failed test cases.
  int UnitTest::failed_test_case_count() const {
    return impl()->failed_test_case_count();
  }
  
  // Gets the number of all test cases.
  int UnitTest::total_test_case_count() const {
    return impl()->total_test_case_count();
  }
  
  // Gets the number of all test cases that contain at least one test
  // that should run.
  int UnitTest::test_case_to_run_count() const {
    return impl()->test_case_to_run_count();
  }
  
  // Gets the number of successful tests.
  int UnitTest::successful_test_count() const {
    return impl()->successful_test_count();
  }
  
  // Gets the number of failed tests.
  int UnitTest::failed_test_count() const { return impl()->failed_test_count(); }
  
  // Gets the number of disabled tests.
  int UnitTest::disabled_test_count() const {
    return impl()->disabled_test_count();
  }
  
  // Gets the number of all tests.
  int UnitTest::total_test_count() const { return impl()->total_test_count(); }
  
  // Gets the number of tests that should run.
  int UnitTest::test_to_run_count() const { return impl()->test_to_run_count(); }
  
  // Gets the elapsed time, in milliseconds.
  internal::TimeInMillis UnitTest::elapsed_time() const {
    return impl()->elapsed_time();
  }
  
  // Returns true iff the unit test passed (i.e. all test cases passed).
  bool UnitTest::Passed() const { return impl()->Passed(); }
  
  // Returns true iff the unit test failed (i.e. some test case failed
  // or something outside of all tests failed).
  bool UnitTest::Failed() const { return impl()->Failed(); }
  
  // Gets the i-th test case among all the test cases. i can range from 0 to
  // total_test_case_count() - 1. If i is not in that range, returns NULL.
  const TestCase* UnitTest::GetTestCase(int i) const {
    return impl()->GetTestCase(i);
  }
  
  // Gets the i-th test case among all the test cases. i can range from 0 to
  // total_test_case_count() - 1. If i is not in that range, returns NULL.
  TestCase* UnitTest::GetMutableTestCase(int i) {
    return impl()->GetMutableTestCase(i);
  }
  
  // Returns the list of event listeners that can be used to track events
  // inside Google Test.
  TestEventListeners& UnitTest::listeners() {
    return *impl()->listeners();
  }
  
  // Registers and returns a global test environment.  When a test
  // program is run, all global test environments will be set-up in the
  // order they were registered.  After all tests in the program have
  // finished, all global test environments will be torn-down in the
  // *reverse* order they were registered.
  //
  // The UnitTest object takes ownership of the given environment.
  //
  // We don't protect this under mutex_, as we only support calling it
  // from the main thread.
  Environment* UnitTest::AddEnvironment(Environment* env) {
    if (env == NULL) {
      return NULL;
    }
  
    impl_->environments()->PushBack(env);
    impl_->environments_in_reverse_order()->PushFront(env);
    return env;
  }
  
  #if GTEST_HAS_EXCEPTIONS
  // A failed Google Test assertion will throw an exception of this type
  // when exceptions are enabled.  We derive it from std::runtime_error,
  // which is for errors presumably detectable only at run time.  Since
  // std::runtime_error inherits from std::exception, many testing
  // frameworks know how to extract and print the message inside it.
  class GoogleTestFailureException : public ::std::runtime_error {
   public:
    explicit GoogleTestFailureException(const TestPartResult& failure)
        : ::std::runtime_error(PrintTestPartResultToString(failure).c_str()) {}
  };
  #endif
  
  // 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.
  // L < mutex_
  void UnitTest::AddTestPartResult(TestPartResult::Type result_type,
                                   const char* file_name,
                                   int line_number,
                                   const internal::String& message,
                                   const internal::String& os_stack_trace) {
    Message msg;
    msg << message;
  
    internal::MutexLock lock(&mutex_);
    if (impl_->gtest_trace_stack()->size() > 0) {
      msg << "\n" << GTEST_NAME_ << " trace:";
  
      for (int i = 0; i < impl_->gtest_trace_stack()->size(); i++) {
        const internal::TraceInfo& trace =
            impl_->gtest_trace_stack()->GetElement(i);
        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
        // 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
        *static_cast<int*>(NULL) = 1;
  #endif  // GTEST_OS_WINDOWS
      } else if (GTEST_FLAG(throw_on_failure)) {
  #if GTEST_HAS_EXCEPTIONS
        throw 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
      }
    }
  }
  
  // Creates and adds a property to the current TestResult. If a property matching
  // the supplied value already exists, updates its value instead.
  void UnitTest::RecordPropertyForCurrentTest(const char* key,
                                              const char* value) {
    const TestProperty test_property(key, value);
    impl_->current_test_result()->RecordProperty(test_property);
  }
  
  // Runs all tests in this UnitTest object and prints the result.
  // Returns 0 if successful, or 1 otherwise.
  //
  // We don't protect this under mutex_, as we only support calling it
  // from the main thread.
  int UnitTest::Run() {
  #if GTEST_HAS_SEH
    // Catch SEH-style exceptions.
  
    const bool in_death_test_child_process =
        internal::GTEST_FLAG(internal_run_death_test).length() > 0;
  
    // Either the user wants Google Test to catch exceptions thrown by the
    // tests or this is executing in the context of death test child
    // process. In either case the user does not want to see pop-up dialogs
    // about crashes - they are expected..
    if (GTEST_FLAG(catch_exceptions) || in_death_test_child_process) {
  #if !GTEST_OS_WINDOWS_MOBILE
      // SetErrorMode doesn't exist on CE.
      SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOALIGNMENTFAULTEXCEPT |
                   SEM_NOGPFAULTERRORBOX | SEM_NOOPENFILEERRORBOX);
  #endif  // !GTEST_OS_WINDOWS_MOBILE
  
  #if (defined(_MSC_VER) || GTEST_OS_WINDOWS_MINGW) && !GTEST_OS_WINDOWS_MOBILE
      // Death test children can be terminated with _abort().  On Windows,
      // _abort() can show a dialog with a warning message.  This forces the
      // abort message to go to stderr instead.
      _set_error_mode(_OUT_TO_STDERR);
  #endif
  
  #if _MSC_VER >= 1400 && !GTEST_OS_WINDOWS_MOBILE
      // In the debug version, Visual Studio pops up a separate dialog
      // offering a choice to debug the aborted program. We need to suppress
      // this dialog or it will pop up for every EXPECT/ASSERT_DEATH statement
      // executed. Google Test will notify the user of any unexpected
      // failure via stderr.
      //
      // VC++ doesn't define _set_abort_behavior() prior to the version 8.0.
      // Users of prior VC versions shall suffer the agony and pain of
      // clicking through the countless debug dialogs.
      // TODO(vladl@google.com): find a way to suppress the abort dialog() in the
      // debug mode when compiled with VC 7.1 or lower.
      if (!GTEST_FLAG(break_on_failure))
        _set_abort_behavior(
            0x0,                                    // Clear the following flags:
            _WRITE_ABORT_MSG | _CALL_REPORTFAULT);  // pop-up window, core dump.
  #endif
    }
  
    __try {
      return impl_->RunAllTests();
    } __except(internal::UnitTestOptions::GTestShouldProcessSEH(
        GetExceptionCode())) {
      printf("Exception thrown with code 0x%x.\nFAIL\n", GetExceptionCode());
      fflush(stdout);
      return 1;
    }
  
  #else  // We are on a compiler or platform that doesn't support SEH.
  
    return impl_->RunAllTests();
  #endif  // GTEST_HAS_SEH
  }
  
  // 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.
  // L < mutex_
  const TestCase* UnitTest::current_test_case() const {
    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.
  // L < mutex_
  const TestInfo* UnitTest::current_test_info() const {
    internal::MutexLock lock(&mutex_);
    return impl_->current_test_info();
  }
  
  // Returns the random seed used at the start of the current test run.
  int UnitTest::random_seed() const { return impl_->random_seed(); }
  
  #if GTEST_HAS_PARAM_TEST
  // Returns ParameterizedTestCaseRegistry object used to keep track of
  // value-parameterized tests and instantiate and register them.
  // L < mutex_
  internal::ParameterizedTestCaseRegistry&
      UnitTest::parameterized_test_registry() {
    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.
  // L < mutex_
  void UnitTest::PushGTestTrace(const internal::TraceInfo& trace) {
    internal::MutexLock lock(&mutex_);
    impl_->gtest_trace_stack()->PushFront(trace);
  }
  
  // Pops a trace from the per-thread Google Test trace stack.
  // L < mutex_
  void UnitTest::PopGTestTrace() {
    internal::MutexLock lock(&mutex_);
    impl_->gtest_trace_stack()->PopFront(NULL);
  }
  
  namespace internal {
  
  UnitTestImpl::UnitTestImpl(UnitTest* parent)
      : parent_(parent),
  #ifdef _MSC_VER
  #pragma warning(push)                    // Saves the current warning state.
  #pragma warning(disable:4355)            // Temporarily disables warning 4355
                                           // (using this in initializer).
        default_global_test_part_result_reporter_(this),
        default_per_thread_test_part_result_reporter_(this),
  #pragma warning(pop)                     // Restores the warning state again.
  #else
        default_global_test_part_result_reporter_(this),
        default_per_thread_test_part_result_reporter_(this),
  #endif  // _MSC_VER
        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.
  #if GTEST_HAS_DEATH_TEST
        elapsed_time_(0),
        internal_run_death_test_flag_(NULL),
        death_test_factory_(new DefaultDeathTestFactory) {
  #else
        elapsed_time_(0) {
  #endif  // GTEST_HAS_DEATH_TEST
    listeners()->SetDefaultResultPrinter(new PrettyUnitTestResultPrinter);
  }
  
  UnitTestImpl::~UnitTestImpl() {
    // Deletes every TestCase.
    test_cases_.ForEach(internal::Delete<TestCase>);
  
    // Deletes every Environment.
    environments_.ForEach(internal::Delete<Environment>);
  
    delete os_stack_trace_getter_;
  }
  
  #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 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);
    }
  }
  
  // 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 GTEST_HAS_DEATH_TEST
      InitDeathTestSubprocessControlInfo();
      SuppressTestEventsIfInSubprocess();
  #endif  // GTEST_HAS_DEATH_TEST
  
      // Registers parameterized tests. This makes parameterized tests
      // available to the UnitTest reflection API without running
      // RUN_ALL_TESTS.
      RegisterParameterizedTests();
  
      // Configures listeners for XML output. This makes it possible for users
      // to shut down the default XML output before invoking RUN_ALL_TESTS.
      ConfigureXmlOutput();
    }
  }
  
  // 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 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:
    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
  //   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* comment,
                                      Test::SetUpTestCaseFunc set_up_tc,
                                      Test::TearDownTestCaseFunc tear_down_tc) {
    // Can we find a TestCase with the given name?
    TestCase** test_case = test_cases_.FindIf(TestCaseNameIs(test_case_name));
  
    if (test_case != NULL)
      return *test_case;
  
    // No.  Let's create one.
    TestCase* const new_test_case =
        new TestCase(test_case_name, comment, set_up_tc, tear_down_tc);
  
    // Is this a death test case?
    if (internal::UnitTestOptions::MatchesFilter(String(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.
      test_cases_.Insert(new_test_case, ++last_death_test_case_);
    } else {
      // No.  Appends to the end of the list.
      test_cases_.PushBack(new_test_case);
    }
  
    test_case_indices_.PushBack(test_case_indices_.size());
    return new_test_case;
  }
  
  // Helpers for setting up / tearing down the given environment.  They
  // are for use in the Vector::ForEach() method.
  static void SetUpEnvironment(Environment* env) { env->SetUp(); }
  static void TearDownEnvironment(Environment* env) { env->TearDown(); }
  
  // Runs all tests in this UnitTest object, prints the result, and
  // returns 0 if all tests are successful, or 1 otherwise.  If any
  // exception is thrown during a test on Windows, this test is
  // considered to be failed, but the rest of the tests will still be
  // run.  (We disable exceptions on Linux and Mac OS X, so the issue
  // doesn't apply there.)
  // When parameterized tests are enabled, it expands and registers
  // parameterized tests first in RegisterParameterizedTests().
  // All other functions called from RunAllTests() may safely assume that
  // parameterized tests are ready to be counted and run.
  int 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 1;
    }
  
    // Do not run any test if the --help flag was specified.
    if (g_help_flag)
      return 0;
  
    // 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);
  #endif  // GTEST_HAS_DEATH_TEST
  
    const bool should_shard = ShouldShard(kTestTotalShards, kTestShardIndex,
                                          in_subprocess_for_death_test);
  
    // Compares the full test names with the filter to decide which
    // tests to run.
    const bool has_tests_to_run = FilterTests(should_shard
                                                ? HONOR_SHARDING_PROTOCOL
                                                : IGNORE_SHARDING_PROTOCOL) > 0;
  
    // Lists the tests and exits if the --gtest_list_tests flag was specified.
    if (GTEST_FLAG(list_tests)) {
      // This must be called *after* FilterTests() has been called.
      ListTestsMatchingFilter();
      return 0;
    }
  
    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();
  
    repeater->OnTestProgramStart(*parent_);
  
    // How many times to repeat the tests?  We don't want to repeat them
    // when we are inside the subprocess of a death test.
    const int repeat = in_subprocess_for_death_test ? 1 : GTEST_FLAG(repeat);
    // Repeats forever if the repeat count is negative.
    const bool forever = repeat < 0;
    for (int i = 0; forever || i != repeat; i++) {
      ClearResult();
  
      const TimeInMillis start = GetTimeInMillis();
  
      // Shuffles test cases and tests if requested.
      if (has_tests_to_run && GTEST_FLAG(shuffle)) {
        random()->Reseed(random_seed_);
        // This should be done before calling OnTestIterationStart(),
        // such that a test event listener can see the actual test order
        // in the event.
        ShuffleTests();
      }
  
      // Tells the unit test event listeners that the tests are about to start.
      repeater->OnTestIterationStart(*parent_, i);
  
      // Runs each test case if there is at least one test to run.
      if (has_tests_to_run) {
        // Sets up all environments beforehand.
        repeater->OnEnvironmentsSetUpStart(*parent_);
        environments_.ForEach(SetUpEnvironment);
        repeater->OnEnvironmentsSetUpEnd(*parent_);
  
        // Runs the tests only if there was no fatal failure during global
        // set-up.
        if (!Test::HasFatalFailure()) {
          for (int i = 0; i < total_test_case_count(); i++) {
            GetMutableTestCase(i)->Run();
          }
        }
  
        // Tears down all environments in reverse order afterwards.
        repeater->OnEnvironmentsTearDownStart(*parent_);
        environments_in_reverse_order_.ForEach(TearDownEnvironment);
        repeater->OnEnvironmentsTearDownEnd(*parent_);
      }
  
      elapsed_time_ = GetTimeInMillis() - start;
  
      // Tells the unit test event listener that the tests have just finished.
      repeater->OnTestIterationEnd(*parent_, i);
  
      // Gets the result and clears it.
      if (!Passed()) {
        failed = true;
      }
  
      // Restores the original test order after the iteration.  This
      // allows the user to quickly repro a failure that happens in the
      // N-th iteration without repeating the first (N - 1) iterations.
      // This is not enclosed in "if (GTEST_FLAG(shuffle)) { ... }", in
      // case the user somehow changes the value of the flag somewhere
      // (it's always safe to unshuffle the tests).
      UnshuffleTests();
  
      if (GTEST_FLAG(shuffle)) {
        // Picks a new random seed for each iteration.
        random_seed_ = GetNextRandomSeed(random_seed_);
      }
    }
  
    repeater->OnTestProgramEnd(*parent_);
  
    // Returns 0 if all tests passed, or 1 other wise.
    return failed ? 1 : 0;
  }
  
  // Reads the GTEST_SHARD_STATUS_FILE environment variable, and creates the file
  // if the variable is present. If a file already exists at this location, this
  // function will write over it. If the variable is present, but the file cannot
  // be created, prints an error and exits.
  void WriteToShardStatusFileIfNeeded() {
    const char* const test_shard_file = posix::GetEnv(kTestShardStatusFile);
    if (test_shard_file != NULL) {
      FILE* const file = posix::FOpen(test_shard_file, "w");
      if (file == NULL) {
        ColoredPrintf(COLOR_RED,
                      "Could not write to the test shard status file \"%s\" "
                      "specified by the %s environment variable.\n",
                      test_shard_file, kTestShardStatusFile);
        fflush(stdout);
        exit(EXIT_FAILURE);
      }
      fclose(file);
    }
  }
  
  // Checks whether sharding is enabled by examining the relevant
  // environment variable values. If the variables are present,
  // but inconsistent (i.e., shard_index >= total_shards), prints
  // an error and exits. If in_subprocess_for_death_test, sharding is
  // disabled because it must only be applied to the original test
  // process. Otherwise, we could filter out death tests we intended to execute.
  bool ShouldShard(const char* total_shards_env,
                   const char* shard_index_env,
                   bool in_subprocess_for_death_test) {
    if (in_subprocess_for_death_test) {
      return false;
    }
  
    const Int32 total_shards = Int32FromEnvOrDie(total_shards_env, -1);
    const Int32 shard_index = Int32FromEnvOrDie(shard_index_env, -1);
  
    if (total_shards == -1 && shard_index == -1) {
      return false;
    } else if (total_shards == -1 && shard_index != -1) {
      const Message msg = Message()
        << "Invalid environment variables: you have "
        << kTestShardIndex << " = " << shard_index
        << ", but have left " << kTestTotalShards << " unset.\n";
      ColoredPrintf(COLOR_RED, msg.GetString().c_str());
      fflush(stdout);
      exit(EXIT_FAILURE);
    } else if (total_shards != -1 && shard_index == -1) {
      const Message msg = Message()
        << "Invalid environment variables: you have "
        << kTestTotalShards << " = " << total_shards
        << ", but have left " << kTestShardIndex << " unset.\n";
      ColoredPrintf(COLOR_RED, msg.GetString().c_str());
      fflush(stdout);
      exit(EXIT_FAILURE);
    } else if (shard_index < 0 || shard_index >= total_shards) {
      const Message msg = Message()
        << "Invalid environment variables: we require 0 <= "
        << kTestShardIndex << " < " << kTestTotalShards
        << ", but you have " << kTestShardIndex << "=" << shard_index
        << ", " << kTestTotalShards << "=" << total_shards << ".\n";
      ColoredPrintf(COLOR_RED, msg.GetString().c_str());
      fflush(stdout);
      exit(EXIT_FAILURE);
    }
  
    return total_shards > 1;
  }
  
  // Parses the environment variable var as an Int32. If it is unset,
  // returns default_val. If it is not an Int32, prints an error
  // and aborts.
  Int32 Int32FromEnvOrDie(const char* const var, Int32 default_val) {
    const char* str_val = posix::GetEnv(var);
    if (str_val == NULL) {
      return default_val;
    }
  
    Int32 result;
    if (!ParseInt32(Message() << "The value of environment variable " << var,
                    str_val, &result)) {
      exit(EXIT_FAILURE);
    }
    return result;
  }
  
  // Given the total number of shards, the shard index, and the test id,
  // returns true iff the test should be run on this shard. The test id is
  // some arbitrary but unique non-negative integer assigned to each test
  // method. Assumes that 0 <= shard_index < total_shards.
  bool ShouldRunTestOnShard(int total_shards, int shard_index, int test_id) {
    return (test_id % total_shards) == shard_index;
  }
  
  // Compares the name of each test with the user-specified filter to
  // decide whether the test should be run, then records the result in
  // each TestCase and TestInfo object.
  // If shard_tests == true, further filters tests based on sharding
  // variables in the environment - see
  // http://code.google.com/p/googletest/wiki/GoogleTestAdvancedGuide.
  // Returns the number of tests that should run.
  int UnitTestImpl::FilterTests(ReactionToSharding shard_tests) {
    const Int32 total_shards = shard_tests == HONOR_SHARDING_PROTOCOL ?
        Int32FromEnvOrDie(kTestTotalShards, -1) : -1;
    const Int32 shard_index = shard_tests == HONOR_SHARDING_PROTOCOL ?
        Int32FromEnvOrDie(kTestShardIndex, -1) : -1;
  
    // num_runnable_tests are the number of tests that will
    // run across all shards (i.e., match filter and are not disabled).
    // num_selected_tests are the number of tests to be run on
    // this shard.
    int num_runnable_tests = 0;
    int num_selected_tests = 0;
    for (int i = 0; i < test_cases_.size(); i++) {
      TestCase* const test_case = test_cases_.GetElement(i);
      const String &test_case_name = test_case->name();
      test_case->set_should_run(false);
  
      for (int j = 0; j < test_case->test_info_list().size(); j++) {
        TestInfo* const test_info = test_case->test_info_list().GetElement(j);
        const 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->impl()->set_is_disabled(is_disabled);
  
        const bool matches_filter =
            internal::UnitTestOptions::FilterMatchesTest(test_case_name,
                                                         test_name);
        test_info->impl()->set_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->impl()->set_should_run(is_selected);
        test_case->set_should_run(test_case->should_run() || is_selected);
      }
    }
    return num_selected_tests;
  }
  
  // Prints the names of the tests matching the user-specified filter flag.
  void UnitTestImpl::ListTestsMatchingFilter() {
    for (int i = 0; i < test_cases_.size(); i++) {
      const TestCase* const test_case = test_cases_.GetElement(i);
      bool printed_test_case_name = false;
  
      for (int j = 0; j < test_case->test_info_list().size(); j++) {
        const TestInfo* const test_info =
            test_case->test_info_list().GetElement(j);
        if (test_info->matches_filter()) {
          if (!printed_test_case_name) {
            printed_test_case_name = true;
            printf("%s.\n", test_case->name());
          }
          printf("  %s\n", test_info->name());
        }
      }
    }
    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) {
      os_stack_trace_getter_ = new OsStackTraceGetter;
    }
  
    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_->impl()->result() : &ad_hoc_test_result_;
  }
  
  // Shuffles all test cases, and the tests within each test case,
  // making sure that death tests are still run first.
  void UnitTestImpl::ShuffleTests() {
    // Shuffles the death test cases.
    test_case_indices_.ShuffleRange(random(), 0, last_death_test_case_ + 1);
  
    // Shuffles the non-death test cases.
    test_case_indices_.ShuffleRange(random(), last_death_test_case_ + 1,
                                    test_cases_.size());
  
    // Shuffles the tests inside each test case.
    for (int i = 0; i < test_cases_.size(); i++) {
      test_cases_.GetElement(i)->ShuffleTests(random());
    }
  }
  
  // Restores the test cases and tests to their order before the first shuffle.
  void UnitTestImpl::UnshuffleTests() {
    for (int i = 0; i < test_cases_.size(); i++) {
      // Unshuffles the tests in each test case.
      test_cases_.GetElement(i)->UnshuffleTests();
      // Resets the index of each test case.
      test_case_indices_.GetMutableElement(i) = i;
    }
  }
  
  // TestInfoImpl constructor. The new instance assumes ownership of the test
  // factory object.
  TestInfoImpl::TestInfoImpl(TestInfo* parent,
                             const char* test_case_name,
                             const char* name,
                             const char* test_case_comment,
                             const char* comment,
                             TypeId fixture_class_id,
                             internal::TestFactoryBase* factory) :
      parent_(parent),
      test_case_name_(String(test_case_name)),
      name_(String(name)),
      test_case_comment_(String(test_case_comment)),
      comment_(String(comment)),
      fixture_class_id_(fixture_class_id),
      should_run_(false),
      is_disabled_(false),
      matches_filter_(false),
      factory_(factory) {
  }
  
  // TestInfoImpl destructor.
  TestInfoImpl::~TestInfoImpl() {
    delete factory_;
  }
  
  // Returns the current OS stack trace as a 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.
  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_HIDE_UNREACHABLE_CODE_ 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;
  }
  
  // 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 String flag_str = String::Format("--%s%s", 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, 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;
  }
  
  // Prints a string containing code-encoded text.  The following escape
  // sequences can be used in the string to control the text color:
  //
  //   @@    prints a single '@' character.
  //   @R    changes the color to red.
  //   @G    changes the color to green.
  //   @Y    changes the color to yellow.
  //   @D    changes to the default terminal text color.
  //
  // TODO(wan@google.com): Write tests for this once we add stdout
  // capturing to Google Test.
  static void PrintColorEncoded(const char* str) {
    GTestColor color = COLOR_DEFAULT;  // The current color.
  
    // Conceptually, we split the string into segments divided by escape
    // sequences.  Then we print one segment at a time.  At the end of
    // each iteration, the str pointer advances to the beginning of the
    // next segment.
    for (;;) {
      const char* p = strchr(str, '@');
      if (p == NULL) {
        ColoredPrintf(color, "%s", str);
        return;
      }
  
      ColoredPrintf(color, "%s", String(str, p - str).c_str());
  
      const char ch = p[1];
      str = p + 2;
      if (ch == '@') {
        ColoredPrintf(color, "@");
      } else if (ch == 'D') {
        color = COLOR_DEFAULT;
      } else if (ch == 'R') {
        color = COLOR_RED;
      } else if (ch == 'G') {
        color = COLOR_GREEN;
      } else if (ch == 'Y') {
        color = COLOR_YELLOW;
      } else {
        --str;
      }
    }
  }
  
  static const char kColorEncodedHelpMessage[] =
  "This program contains tests written using " GTEST_NAME_ ". You can use the\n"
  "following command line flags to control its behavior:\n"
  "\n"
  "Test Selection:\n"
  "  @G--" GTEST_FLAG_PREFIX_ "list_tests@D\n"
  "      List the names of all tests instead of running them. The name of\n"
  "      TEST(Foo, Bar) is \"Foo.Bar\".\n"
  "  @G--" GTEST_FLAG_PREFIX_ "filter=@YPOSTIVE_PATTERNS"
      "[@G-@YNEGATIVE_PATTERNS]@D\n"
  "      Run only the tests whose name matches one of the positive patterns but\n"
  "      none of the negative patterns. '?' matches any single character; '*'\n"
  "      matches any substring; ':' separates two patterns.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "also_run_disabled_tests@D\n"
  "      Run all disabled tests too.\n"
  "\n"
  "Test Execution:\n"
  "  @G--" GTEST_FLAG_PREFIX_ "repeat=@Y[COUNT]@D\n"
  "      Run the tests repeatedly; use a negative count to repeat forever.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "shuffle@D\n"
  "      Randomize tests' orders on every iteration.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "random_seed=@Y[NUMBER]@D\n"
  "      Random number seed to use for shuffling test orders (between 1 and\n"
  "      99999, or 0 to use a seed based on the current time).\n"
  "\n"
  "Test Output:\n"
  "  @G--" GTEST_FLAG_PREFIX_ "color=@Y(@Gyes@Y|@Gno@Y|@Gauto@Y)@D\n"
  "      Enable/disable colored output. The default is @Gauto@D.\n"
  "  -@G-" GTEST_FLAG_PREFIX_ "print_time=0@D\n"
  "      Don't print the elapsed time of each test.\n"
  "  @G--" GTEST_FLAG_PREFIX_ "output=xml@Y[@G:@YDIRECTORY_PATH@G"
      GTEST_PATH_SEP_ "@Y|@G:@YFILE_PATH]@D\n"
  "      Generate an XML report in the given directory or with the given file\n"
  "      name. @YFILE_PATH@D defaults to @Gtest_details.xml@D.\n"
  "\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"
  #if GTEST_OS_WINDOWS
  "  @G--" GTEST_FLAG_PREFIX_ "catch_exceptions@D\n"
  "      Suppress pop-ups caused by exceptions.\n"
  #endif  // GTEST_OS_WINDOWS
  "\n"
  "Except for @G--" GTEST_FLAG_PREFIX_ "list_tests@D, you can alternatively set "
      "the corresponding\n"
  "environment variable of a flag (all letters in upper-case). For example, to\n"
  "disable colored text output, you can either specify @G--" GTEST_FLAG_PREFIX_
      "color=no@D or set\n"
  "the @G" GTEST_FLAG_PREFIX_UPPER_ "COLOR@D environment variable to @Gno@D.\n"
  "\n"
  "For more information, please read the " GTEST_NAME_ " documentation at\n"
  "@G" GTEST_PROJECT_URL_ "@D. If you find a bug in " GTEST_NAME_ "\n"
  "(not one in your own code or tests), please report it to\n"
  "@G<" GTEST_DEV_EMAIL_ ">@D.\n";
  
  // 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 String arg_string = StreamableToString(argv[i]);
      const char* const arg = arg_string.c_str();
  
      using internal::ParseBoolFlag;
      using internal::ParseInt32Flag;
      using internal::ParseStringFlag;
  
      // Do we see a Google Test flag?
      if (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)) ||
          ParseBoolFlag(arg, kThrowOnFailureFlag, &GTEST_FLAG(throw_on_failure))
          ) {
        // Yes.  Shift the remainder of the argv list left by one.  Note
        // that argv has (*argc + 1) elements, the last one always being
        // NULL.  The following loop moves the trailing NULL element as
        // well.
        for (int j = i; j != *argc; j++) {
          argv[j] = argv[j + 1];
        }
  
        // Decrements the argument count.
        (*argc)--;
  
        // We also need to decrement the iterator as we just removed
        // an element.
        i--;
      } else if (arg_string == "--help" || arg_string == "-h" ||
                 arg_string == "-?" || arg_string == "/?") {
        g_help_flag = true;
      }
    }
  
    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) {
    g_init_gtest_count++;
  
    // We don't want to run the initialization code twice.
    if (g_init_gtest_count != 1) return;
  
    if (*argc <= 0) return;
  
    internal::g_executable_path = internal::StreamableToString(argv[0]);
  
  #if GTEST_HAS_DEATH_TEST
    g_argvs.clear();
    for (int i = 0; i != *argc; i++) {
      g_argvs.push_back(StreamableToString(argv[i]));
    }
  #endif  // GTEST_HAS_DEATH_TEST
  
    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) {
    internal::InitGoogleTestImpl(argc, argv);
  }
  
  // This overloaded version can be used in Windows programs compiled in
  // UNICODE mode.
  void InitGoogleTest(int* argc, wchar_t** argv) {
    internal::InitGoogleTestImpl(argc, argv);
  }
  
  }  // namespace testing
  