googletest/googletest/test/googletest-port-test.cc

// Copyright 2008, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// This file tests the internal cross-platform support utilities.
#include <stdio.h>

#include "gtest/internal/gtest-port.h"

#ifdef GTEST_OS_MAC
#include <time.h>
#endif  // GTEST_OS_MAC

#include <chrono>  // NOLINT
#include <list>
#include <memory>
#include <string>
#include <thread>   // NOLINT
#include <utility>  // For std::pair and std::make_pair.
#include <vector>

#include "gtest/gtest-spi.h"
#include "gtest/gtest.h"
#include "src/gtest-internal-inl.h"

using std::make_pair;
using std::pair;

namespace testing {
namespace internal {

TEST(IsXDigitTest, WorksForNarrowAscii) {
  EXPECT_TRUE(IsXDigit('0'));
  EXPECT_TRUE(IsXDigit('9'));
  EXPECT_TRUE(IsXDigit('A'));
  EXPECT_TRUE(IsXDigit('F'));
  EXPECT_TRUE(IsXDigit('a'));
  EXPECT_TRUE(IsXDigit('f'));

  EXPECT_FALSE(IsXDigit('-'));
  EXPECT_FALSE(IsXDigit('g'));
  EXPECT_FALSE(IsXDigit('G'));
}

TEST(IsXDigitTest, ReturnsFalseForNarrowNonAscii) {
  EXPECT_FALSE(IsXDigit(static_cast<char>('\x80')));
  EXPECT_FALSE(IsXDigit(static_cast<char>('0' | '\x80')));
}

TEST(IsXDigitTest, WorksForWideAscii) {
  EXPECT_TRUE(IsXDigit(L'0'));
  EXPECT_TRUE(IsXDigit(L'9'));
  EXPECT_TRUE(IsXDigit(L'A'));
  EXPECT_TRUE(IsXDigit(L'F'));
  EXPECT_TRUE(IsXDigit(L'a'));
  EXPECT_TRUE(IsXDigit(L'f'));

  EXPECT_FALSE(IsXDigit(L'-'));
  EXPECT_FALSE(IsXDigit(L'g'));
  EXPECT_FALSE(IsXDigit(L'G'));
}

TEST(IsXDigitTest, ReturnsFalseForWideNonAscii) {
  EXPECT_FALSE(IsXDigit(static_cast<wchar_t>(0x80)));
  EXPECT_FALSE(IsXDigit(static_cast<wchar_t>(L'0' | 0x80)));
  EXPECT_FALSE(IsXDigit(static_cast<wchar_t>(L'0' | 0x100)));
}

class Base {
 public:
  Base() : member_(0) {}
  explicit Base(int n) : member_(n) {}
  Base(const Base&) = default;
  Base& operator=(const Base&) = default;
  virtual ~Base() = default;
  int member() { return member_; }

 private:
  int member_;
};

class Derived : public Base {
 public:
  explicit Derived(int n) : Base(n) {}
};

TEST(ImplicitCastTest, ConvertsPointers) {
  Derived derived(0);
  EXPECT_TRUE(&derived == ::testing::internal::ImplicitCast_<Base*>(&derived));
}

TEST(ImplicitCastTest, CanUseInheritance) {
  Derived derived(1);
  Base base = ::testing::internal::ImplicitCast_<Base>(derived);
  EXPECT_EQ(derived.member(), base.member());
}

class Castable {
 public:
  explicit Castable(bool* converted) : converted_(converted) {}
  operator Base() {
    *converted_ = true;
    return Base();
  }

 private:
  bool* converted_;
};

TEST(ImplicitCastTest, CanUseNonConstCastOperator) {
  bool converted = false;
  Castable castable(&converted);
  Base base = ::testing::internal::ImplicitCast_<Base>(castable);
  EXPECT_TRUE(converted);
}

class ConstCastable {
 public:
  explicit ConstCastable(bool* converted) : converted_(converted) {}
  operator Base() const {
    *converted_ = true;
    return Base();
  }

 private:
  bool* converted_;
};

TEST(ImplicitCastTest, CanUseConstCastOperatorOnConstValues) {
  bool converted = false;
  const ConstCastable const_castable(&converted);
  Base base = ::testing::internal::ImplicitCast_<Base>(const_castable);
  EXPECT_TRUE(converted);
}

class ConstAndNonConstCastable {
 public:
  ConstAndNonConstCastable(bool* converted, bool* const_converted)
      : converted_(converted), const_converted_(const_converted) {}
  operator Base() {
    *converted_ = true;
    return Base();
  }
  operator Base() const {
    *const_converted_ = true;
    return Base();
  }

 private:
  bool* converted_;
  bool* const_converted_;
};

TEST(ImplicitCastTest, CanSelectBetweenConstAndNonConstCasrAppropriately) {
  bool converted = false;
  bool const_converted = false;
  ConstAndNonConstCastable castable(&converted, &const_converted);
  Base base = ::testing::internal::ImplicitCast_<Base>(castable);
  EXPECT_TRUE(converted);
  EXPECT_FALSE(const_converted);

  converted = false;
  const_converted = false;
  const ConstAndNonConstCastable const_castable(&converted, &const_converted);
  base = ::testing::internal::ImplicitCast_<Base>(const_castable);
  EXPECT_FALSE(converted);
  EXPECT_TRUE(const_converted);
}

class To {
 public:
  To(bool* converted) { *converted = true; }  // NOLINT
};

TEST(ImplicitCastTest, CanUseImplicitConstructor) {
  bool converted = false;
  To to = ::testing::internal::ImplicitCast_<To>(&converted);
  (void)to;
  EXPECT_TRUE(converted);
}

// The following code intentionally tests a suboptimal syntax.
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdangling-else"
#pragma GCC diagnostic ignored "-Wempty-body"
#pragma GCC diagnostic ignored "-Wpragmas"
#endif
TEST(GtestCheckSyntaxTest, BehavesLikeASingleStatement) {
  if (AlwaysFalse())
    GTEST_CHECK_(false) << "This should never be executed; "
                           "It's a compilation test only.";

  if (AlwaysTrue())
    GTEST_CHECK_(true);
  else
    ;  // NOLINT

  if (AlwaysFalse())
    ;  // NOLINT
  else
    GTEST_CHECK_(true) << "";
}
#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif

TEST(GtestCheckSyntaxTest, WorksWithSwitch) {
  switch (0) {
    case 1:
      break;
    default:
      GTEST_CHECK_(true);
  }

  switch (0)
  case 0:
    GTEST_CHECK_(true) << "Check failed in switch case";
}

// Verifies behavior of FormatFileLocation.
TEST(FormatFileLocationTest, FormatsFileLocation) {
  EXPECT_PRED_FORMAT2(IsSubstring, "foo.cc", FormatFileLocation("foo.cc", 42));
  EXPECT_PRED_FORMAT2(IsSubstring, "42", FormatFileLocation("foo.cc", 42));
}

TEST(FormatFileLocationTest, FormatsUnknownFile) {
  EXPECT_PRED_FORMAT2(IsSubstring, "unknown file",
                      FormatFileLocation(nullptr, 42));
  EXPECT_PRED_FORMAT2(IsSubstring, "42", FormatFileLocation(nullptr, 42));
}

TEST(FormatFileLocationTest, FormatsUknownLine) {
  EXPECT_EQ("foo.cc:", FormatFileLocation("foo.cc", -1));
}

TEST(FormatFileLocationTest, FormatsUknownFileAndLine) {
  EXPECT_EQ("unknown file:", FormatFileLocation(nullptr, -1));
}

// Verifies behavior of FormatCompilerIndependentFileLocation.
TEST(FormatCompilerIndependentFileLocationTest, FormatsFileLocation) {
  EXPECT_EQ("foo.cc:42", FormatCompilerIndependentFileLocation("foo.cc", 42));
}

TEST(FormatCompilerIndependentFileLocationTest, FormatsUknownFile) {
  EXPECT_EQ("unknown file:42",
            FormatCompilerIndependentFileLocation(nullptr, 42));
}

TEST(FormatCompilerIndependentFileLocationTest, FormatsUknownLine) {
  EXPECT_EQ("foo.cc", FormatCompilerIndependentFileLocation("foo.cc", -1));
}

TEST(FormatCompilerIndependentFileLocationTest, FormatsUknownFileAndLine) {
  EXPECT_EQ("unknown file", FormatCompilerIndependentFileLocation(nullptr, -1));
}

#if defined(GTEST_OS_LINUX) || defined(GTEST_OS_MAC) ||           \
    defined(GTEST_OS_QNX) || defined(GTEST_OS_FUCHSIA) ||         \
    defined(GTEST_OS_DRAGONFLY) || defined(GTEST_OS_FREEBSD) ||   \
    defined(GTEST_OS_GNU_KFREEBSD) || defined(GTEST_OS_NETBSD) || \
    defined(GTEST_OS_OPENBSD) || defined(GTEST_OS_GNU_HURD)
void* ThreadFunc(void* data) {
  internal::Mutex* mutex = static_cast<internal::Mutex*>(data);
  mutex->lock();
  mutex->unlock();
  return nullptr;
}

TEST(GetThreadCountTest, ReturnsCorrectValue) {
  size_t starting_count;
  size_t thread_count_after_create;
  size_t thread_count_after_join = 0;

  // We can't guarantee that no other thread was created or destroyed between
  // any two calls to GetThreadCount(). We make multiple attempts, hoping that
  // background noise is not constant and we would see the "right" values at
  // some point.
  for (int attempt = 0; attempt < 20; ++attempt) {
    starting_count = GetThreadCount();
    pthread_t thread_id;

    internal::Mutex mutex;
    {
      internal::MutexLock lock(mutex);
      pthread_attr_t attr;
      ASSERT_EQ(0, pthread_attr_init(&attr));
      ASSERT_EQ(0, pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE));

      const int status = pthread_create(&thread_id, &attr, &ThreadFunc, &mutex);
      ASSERT_EQ(0, pthread_attr_destroy(&attr));
      ASSERT_EQ(0, status);

      thread_count_after_create = GetThreadCount();
    }

    void* dummy;
    ASSERT_EQ(0, pthread_join(thread_id, &dummy));

    // Join before we decide whether we need to retry the test. Retry if an
    // arbitrary other thread was created or destroyed in the meantime.
    if (thread_count_after_create != starting_count + 1) continue;

    // The OS may not immediately report the updated thread count after
    // joining a thread, causing flakiness in this test. To counter that, we
    // wait for up to .5 seconds for the OS to report the correct value.
    bool thread_count_matches = false;
    for (int i = 0; i < 5; ++i) {
      thread_count_after_join = GetThreadCount();
      if (thread_count_after_join == starting_count) {
        thread_count_matches = true;
        break;
      }

      std::this_thread::sleep_for(std::chrono::milliseconds(100));
    }

    // Retry if an arbitrary other thread was created or destroyed.
    if (!thread_count_matches) continue;

    break;
  }

  EXPECT_EQ(thread_count_after_create, starting_count + 1);
  EXPECT_EQ(thread_count_after_join, starting_count);
}
#else
TEST(GetThreadCountTest, ReturnsZeroWhenUnableToCountThreads) {
  EXPECT_EQ(0U, GetThreadCount());
}
#endif  // GTEST_OS_LINUX || GTEST_OS_MAC || GTEST_OS_QNX || GTEST_OS_FUCHSIA

TEST(GtestCheckDeathTest, DiesWithCorrectOutputOnFailure) {
  const bool a_false_condition = false;
  const char regex[] =
#ifdef _MSC_VER
      "googletest-port-test\\.cc\\(\\d+\\):"
#elif defined(GTEST_USES_POSIX_RE)
      "googletest-port-test\\.cc:[0-9]+"
#else
      "googletest-port-test\\.cc:\\d+"
#endif  // _MSC_VER
      ".*a_false_condition.*Extra info.*";

  EXPECT_DEATH_IF_SUPPORTED(GTEST_CHECK_(a_false_condition) << "Extra info",
                            regex);
}

#ifdef GTEST_HAS_DEATH_TEST

TEST(GtestCheckDeathTest, LivesSilentlyOnSuccess) {
  EXPECT_EXIT(
      {
        GTEST_CHECK_(true) << "Extra info";
        ::std::cerr << "Success\n";
        exit(0);
      },
      ::testing::ExitedWithCode(0), "Success");
}

#endif  // GTEST_HAS_DEATH_TEST

// Verifies that Google Test choose regular expression engine appropriate to
// the platform. The test will produce compiler errors in case of failure.
// For simplicity, we only cover the most important platforms here.
TEST(RegexEngineSelectionTest, SelectsCorrectRegexEngine) {
#ifdef GTEST_HAS_ABSL
  EXPECT_TRUE(GTEST_USES_RE2);
#elif GTEST_HAS_POSIX_RE
  EXPECT_TRUE(GTEST_USES_POSIX_RE);
#else
  EXPECT_TRUE(GTEST_USES_STD_RE);
#endif
}

#if defined(GTEST_USES_POSIX_RE) || defined(GTEST_USES_STD_RE)

template <typename Str>
class RETest : public ::testing::Test {};

// Defines StringTypes as the list of all string types that class RE
// supports.
typedef testing::Types< ::std::string, const char*> StringTypes;

TYPED_TEST_SUITE(RETest, StringTypes);

// Tests RE's implicit constructors.
TYPED_TEST(RETest, ImplicitConstructorWorks) {
  const RE empty(TypeParam(""));
  EXPECT_STREQ("", empty.pattern());

  const RE simple(TypeParam("hello"));
  EXPECT_STREQ("hello", simple.pattern());

  const RE normal(TypeParam(".*(\\w+)"));
  EXPECT_STREQ(".*(\\w+)", normal.pattern());
}

// Tests that RE's constructors reject invalid regular expressions.
TYPED_TEST(RETest, RejectsInvalidRegex) {
#ifdef GTEST_USES_POSIX_RE
  EXPECT_NONFATAL_FAILURE(
      { const RE invalid(TypeParam("?")); },
      "\"?\" is not a valid POSIX Extended regular expression.");
#elif GTEST_USES_STD_RE && GTEST_HAS_EXCEPTIONS
  EXPECT_NONFATAL_FAILURE(
      { const RE invalid(TypeParam("?")); },
      "\"?\" is not a valid regular expression");
#endif
}

// Tests RE::FullMatch().
TYPED_TEST(RETest, FullMatchWorks) {
  const RE empty(TypeParam(""));
  EXPECT_TRUE(RE::FullMatch(TypeParam(""), empty));
  EXPECT_FALSE(RE::FullMatch(TypeParam("a"), empty));

  const RE re(TypeParam("a.*z"));
  EXPECT_TRUE(RE::FullMatch(TypeParam("az"), re));
  EXPECT_TRUE(RE::FullMatch(TypeParam("axyz"), re));
  EXPECT_FALSE(RE::FullMatch(TypeParam("baz"), re));
  EXPECT_FALSE(RE::FullMatch(TypeParam("azy"), re));
}

// Tests RE::PartialMatch().
TYPED_TEST(RETest, PartialMatchWorks) {
  const RE empty(TypeParam(""));
  EXPECT_TRUE(RE::PartialMatch(TypeParam(""), empty));
  EXPECT_TRUE(RE::PartialMatch(TypeParam("a"), empty));

  const RE re(TypeParam("a.*z"));
  EXPECT_TRUE(RE::PartialMatch(TypeParam("az"), re));
  EXPECT_TRUE(RE::PartialMatch(TypeParam("axyz"), re));
  EXPECT_TRUE(RE::PartialMatch(TypeParam("baz"), re));
  EXPECT_TRUE(RE::PartialMatch(TypeParam("azy"), re));
  EXPECT_FALSE(RE::PartialMatch(TypeParam("zza"), re));
}

#endif  // GTEST_USES_POSIX_RE || GTEST_USES_STD_RE

#ifndef GTEST_OS_WINDOWS_MOBILE

TEST(CaptureTest, CapturesStdout) {
  CaptureStdout();
  fprintf(stdout, "abc");
  EXPECT_STREQ("abc", GetCapturedStdout().c_str());

  CaptureStdout();
  fprintf(stdout, "def%cghi", '\0');
  EXPECT_EQ(::std::string("def\0ghi", 7), ::std::string(GetCapturedStdout()));
}

TEST(CaptureTest, CapturesStderr) {
  CaptureStderr();
  fprintf(stderr, "jkl");
  EXPECT_STREQ("jkl", GetCapturedStderr().c_str());

  CaptureStderr();
  fprintf(stderr, "jkl%cmno", '\0');
  EXPECT_EQ(::std::string("jkl\0mno", 7), ::std::string(GetCapturedStderr()));
}

// Tests that stdout and stderr capture don't interfere with each other.
TEST(CaptureTest, CapturesStdoutAndStderr) {
  CaptureStdout();
  CaptureStderr();
  fprintf(stdout, "pqr");
  fprintf(stderr, "stu");
  EXPECT_STREQ("pqr", GetCapturedStdout().c_str());
  EXPECT_STREQ("stu", GetCapturedStderr().c_str());
}

TEST(CaptureDeathTest, CannotReenterStdoutCapture) {
  CaptureStdout();
  EXPECT_DEATH_IF_SUPPORTED(CaptureStdout(),
                            "Only one stdout capturer can exist at a time");
  GetCapturedStdout();

  // We cannot test stderr capturing using death tests as they use it
  // themselves.
}

#endif  // !GTEST_OS_WINDOWS_MOBILE

TEST(ThreadLocalTest, DefaultConstructorInitializesToDefaultValues) {
  ThreadLocal<int> t1;
  EXPECT_EQ(0, t1.get());

  ThreadLocal<void*> t2;
  EXPECT_TRUE(t2.get() == nullptr);
}

TEST(ThreadLocalTest, SingleParamConstructorInitializesToParam) {
  ThreadLocal<int> t1(123);
  EXPECT_EQ(123, t1.get());

  int i = 0;
  ThreadLocal<int*> t2(&i);
  EXPECT_EQ(&i, t2.get());
}

class NoDefaultConstructor {
 public:
  explicit NoDefaultConstructor(const char*) {}
  NoDefaultConstructor(const NoDefaultConstructor&) = default;
};

TEST(ThreadLocalTest, ValueDefaultContructorIsNotRequiredForParamVersion) {
  ThreadLocal<NoDefaultConstructor> bar(NoDefaultConstructor("foo"));
  bar.pointer();
}

TEST(ThreadLocalTest, GetAndPointerReturnSameValue) {
  ThreadLocal<std::string> thread_local_string;

  EXPECT_EQ(thread_local_string.pointer(), &(thread_local_string.get()));

  // Verifies the condition still holds after calling set.
  thread_local_string.set("foo");
  EXPECT_EQ(thread_local_string.pointer(), &(thread_local_string.get()));
}

TEST(ThreadLocalTest, PointerAndConstPointerReturnSameValue) {
  ThreadLocal<std::string> thread_local_string;
  const ThreadLocal<std::string>& const_thread_local_string =
      thread_local_string;

  EXPECT_EQ(thread_local_string.pointer(), const_thread_local_string.pointer());

  thread_local_string.set("foo");
  EXPECT_EQ(thread_local_string.pointer(), const_thread_local_string.pointer());
}

#ifdef GTEST_IS_THREADSAFE

void AddTwo(int* param) { *param += 2; }

TEST(ThreadWithParamTest, ConstructorExecutesThreadFunc) {
  int i = 40;
  ThreadWithParam<int*> thread(&AddTwo, &i, nullptr);
  thread.Join();
  EXPECT_EQ(42, i);
}

TEST(MutexDeathTest, AssertHeldShouldAssertWhenNotLocked) {
  // AssertHeld() is flaky only in the presence of multiple threads accessing
  // the lock. In this case, the test is robust.
  EXPECT_DEATH_IF_SUPPORTED(
      {
        Mutex m;
        {
          MutexLock lock(m);
        }
        m.AssertHeld();
      },
      "thread .*hold");
}

TEST(MutexTest, AssertHeldShouldNotAssertWhenLocked) {
  Mutex m;
  MutexLock lock(m);
  m.AssertHeld();
}

class AtomicCounterWithMutex {
 public:
  explicit AtomicCounterWithMutex(Mutex& mutex)
      : value_(0), mutex_(mutex), random_(42) {}

  void Increment() {
    MutexLock lock(mutex_);
    int temp = value_;
    {
      // We need to put up a memory barrier to prevent reads and writes to
      // value_ rearranged with the call to sleep_for when observed
      // from other threads.
#if GTEST_HAS_PTHREAD
      // On POSIX, locking a mutex puts up a memory barrier.  We cannot use
      // Mutex and MutexLock here or rely on their memory barrier
      // functionality as we are testing them here.
      pthread_mutex_t memory_barrier_mutex;
      GTEST_CHECK_POSIX_SUCCESS_(
          pthread_mutex_init(&memory_barrier_mutex, nullptr));
      GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_lock(&memory_barrier_mutex));

      std::this_thread::sleep_for(
          std::chrono::milliseconds(random_.Generate(30)));

      GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_unlock(&memory_barrier_mutex));
      GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_destroy(&memory_barrier_mutex));
#elif defined(GTEST_OS_WINDOWS)
      // On Windows, performing an interlocked access puts up a memory barrier.
      volatile LONG dummy = 0;
      ::InterlockedIncrement(&dummy);
      std::this_thread::sleep_for(
          std::chrono::milliseconds(random_.Generate(30)));
      ::InterlockedIncrement(&dummy);
#else
#error "Memory barrier not implemented on this platform."
#endif  // GTEST_HAS_PTHREAD
    }
    value_ = temp + 1;
  }
  int value() const { return value_; }

 private:
  volatile int value_;
  Mutex& mutex_;  // Protects value_.
  Random random_;
};

void CountingThreadFunc(pair<AtomicCounterWithMutex*, int> param) {
  for (int i = 0; i < param.second; ++i) param.first->Increment();
}

// Tests that the mutex only lets one thread at a time to lock it.
TEST(MutexTest, OnlyOneThreadCanLockAtATime) {
  Mutex mutex;
  AtomicCounterWithMutex locked_counter(mutex);

  typedef ThreadWithParam<pair<AtomicCounterWithMutex*, int> > ThreadType;
  const int kCycleCount = 20;
  const int kThreadCount = 7;
  std::unique_ptr<ThreadType> counting_threads[kThreadCount];
  Notification threads_can_start;
  // Creates and runs kThreadCount threads that increment locked_counter
  // kCycleCount times each.
  for (int i = 0; i < kThreadCount; ++i) {
    counting_threads[i] = std::make_unique<ThreadType>(
        &CountingThreadFunc, make_pair(&locked_counter, kCycleCount),
        &threads_can_start);
  }
  threads_can_start.Notify();
  for (int i = 0; i < kThreadCount; ++i) counting_threads[i]->Join();

  // If the mutex lets more than one thread to increment the counter at a
  // time, they are likely to encounter a race condition and have some
  // increments overwritten, resulting in the lower then expected counter
  // value.
  EXPECT_EQ(kCycleCount * kThreadCount, locked_counter.value());
}

template <typename T>
void RunFromThread(void(func)(T), T param) {
  ThreadWithParam<T> thread(func, param, nullptr);
  thread.Join();
}

void RetrieveThreadLocalValue(
    pair<ThreadLocal<std::string>*, std::string*> param) {
  *param.second = param.first->get();
}

TEST(ThreadLocalTest, ParameterizedConstructorSetsDefault) {
  ThreadLocal<std::string> thread_local_string("foo");
  EXPECT_STREQ("foo", thread_local_string.get().c_str());

  thread_local_string.set("bar");
  EXPECT_STREQ("bar", thread_local_string.get().c_str());

  std::string result;
  RunFromThread(&RetrieveThreadLocalValue,
                make_pair(&thread_local_string, &result));
  EXPECT_STREQ("foo", result.c_str());
}

// Keeps track of whether of destructors being called on instances of
// DestructorTracker.  On Windows, waits for the destructor call reports.
class DestructorCall {
 public:
  DestructorCall() {
    invoked_ = false;
#ifdef GTEST_OS_WINDOWS
    wait_event_.Reset(::CreateEvent(NULL, TRUE, FALSE, NULL));
    GTEST_CHECK_(wait_event_.Get() != NULL);
#endif
  }

  bool CheckDestroyed() const {
#ifdef GTEST_OS_WINDOWS
    if (::WaitForSingleObject(wait_event_.Get(), 1000) != WAIT_OBJECT_0)
      return false;
#endif
    return invoked_;
  }

  void ReportDestroyed() {
    invoked_ = true;
#ifdef GTEST_OS_WINDOWS
    ::SetEvent(wait_event_.Get());
#endif
  }

  static std::vector<DestructorCall*>& List() { return *list_; }

  static void ResetList() {
    for (size_t i = 0; i < list_->size(); ++i) {
      delete list_->at(i);
    }
    list_->clear();
  }

 private:
  bool invoked_;
#ifdef GTEST_OS_WINDOWS
  AutoHandle wait_event_;
#endif
  static std::vector<DestructorCall*>* const list_;

  DestructorCall(const DestructorCall&) = delete;
  DestructorCall& operator=(const DestructorCall&) = delete;
};

std::vector<DestructorCall*>* const DestructorCall::list_ =
    new std::vector<DestructorCall*>;

// DestructorTracker keeps track of whether its instances have been
// destroyed.
class DestructorTracker {
 public:
  DestructorTracker() : index_(GetNewIndex()) {}
  DestructorTracker(const DestructorTracker& /* rhs */)
      : index_(GetNewIndex()) {}
  ~DestructorTracker() {
    // We never access DestructorCall::List() concurrently, so we don't need
    // to protect this access with a mutex.
    DestructorCall::List()[index_]->ReportDestroyed();
  }

 private:
  static size_t GetNewIndex() {
    DestructorCall::List().push_back(new DestructorCall);
    return DestructorCall::List().size() - 1;
  }
  const size_t index_;
};

typedef ThreadLocal<DestructorTracker>* ThreadParam;

void CallThreadLocalGet(ThreadParam thread_local_param) {
  thread_local_param->get();
}

// Tests that when a ThreadLocal object dies in a thread, it destroys
// the managed object for that thread.
TEST(ThreadLocalTest, DestroysManagedObjectForOwnThreadWhenDying) {
  DestructorCall::ResetList();

  {
    ThreadLocal<DestructorTracker> thread_local_tracker;
    ASSERT_EQ(0U, DestructorCall::List().size());

    // This creates another DestructorTracker object for the main thread.
    thread_local_tracker.get();
    ASSERT_EQ(1U, DestructorCall::List().size());
    ASSERT_FALSE(DestructorCall::List()[0]->CheckDestroyed());
  }

  // Now thread_local_tracker has died.
  ASSERT_EQ(1U, DestructorCall::List().size());
  EXPECT_TRUE(DestructorCall::List()[0]->CheckDestroyed());

  DestructorCall::ResetList();
}

// Tests that when a thread exits, the thread-local object for that
// thread is destroyed.
TEST(ThreadLocalTest, DestroysManagedObjectAtThreadExit) {
  DestructorCall::ResetList();

  {
    ThreadLocal<DestructorTracker> thread_local_tracker;
    ASSERT_EQ(0U, DestructorCall::List().size());

    // This creates another DestructorTracker object in the new thread.
    ThreadWithParam<ThreadParam> thread(&CallThreadLocalGet,
                                        &thread_local_tracker, nullptr);
    thread.Join();

    // The thread has exited, and we should have a DestroyedTracker
    // instance created for it. But it may not have been destroyed yet.
    ASSERT_EQ(1U, DestructorCall::List().size());
  }

  // The thread has exited and thread_local_tracker has died.
  ASSERT_EQ(1U, DestructorCall::List().size());
  EXPECT_TRUE(DestructorCall::List()[0]->CheckDestroyed());

  DestructorCall::ResetList();
}

TEST(ThreadLocalTest, ThreadLocalMutationsAffectOnlyCurrentThread) {
  ThreadLocal<std::string> thread_local_string;
  thread_local_string.set("Foo");
  EXPECT_STREQ("Foo", thread_local_string.get().c_str());

  std::string result;
  RunFromThread(&RetrieveThreadLocalValue,
                make_pair(&thread_local_string, &result));
  EXPECT_TRUE(result.empty());
}

#endif  // GTEST_IS_THREADSAFE

#ifdef GTEST_OS_WINDOWS
TEST(WindowsTypesTest, HANDLEIsVoidStar) {
  StaticAssertTypeEq<HANDLE, void*>();
}

#if defined(GTEST_OS_WINDOWS_MINGW) && !defined(__MINGW64_VERSION_MAJOR)
TEST(WindowsTypesTest, _CRITICAL_SECTIONIs_CRITICAL_SECTION) {
  StaticAssertTypeEq<CRITICAL_SECTION, _CRITICAL_SECTION>();
}
#else
TEST(WindowsTypesTest, CRITICAL_SECTIONIs_RTL_CRITICAL_SECTION) {
  StaticAssertTypeEq<CRITICAL_SECTION, _RTL_CRITICAL_SECTION>();
}
#endif

#endif  // GTEST_OS_WINDOWS

}  // namespace internal
}  // namespace testing