base/timeutils_unittest.cc - src/webrtc - Git at Google

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */

 #include "webrtc/base/event.h"
 #include "webrtc/base/fakeclock.h"
 #include "webrtc/base/gunit.h"
 #include "webrtc/base/helpers.h"
 #include "webrtc/base/thread.h"
 #include "webrtc/base/timeutils.h"

 namespace rtc {

 TEST(TimeTest, TimeInMs) {
   int64_t ts_earlier = TimeMillis();
   Thread::SleepMs(100);
   int64_t ts_now = TimeMillis();
   // Allow for the thread to wakeup ~20ms early.
   EXPECT_GE(ts_now, ts_earlier + 80);
   // Make sure the Time is not returning in smaller unit like microseconds.
   EXPECT_LT(ts_now, ts_earlier + 1000);
 }

 TEST(TimeTest, Intervals) {
   int64_t ts_earlier = TimeMillis();
   int64_t ts_later = TimeAfter(500);

   // We can't depend on ts_later and ts_earlier to be exactly 500 apart
   // since time elapses between the calls to TimeMillis() and TimeAfter(500)
   EXPECT_LE(500,  TimeDiff(ts_later, ts_earlier));
   EXPECT_GE(-500, TimeDiff(ts_earlier, ts_later));

   // Time has elapsed since ts_earlier
   EXPECT_GE(TimeSince(ts_earlier), 0);

   // ts_earlier is earlier than now, so TimeUntil ts_earlier is -ve
   EXPECT_LE(TimeUntil(ts_earlier), 0);

   // ts_later likely hasn't happened yet, so TimeSince could be -ve
   // but within 500
   EXPECT_GE(TimeSince(ts_later), -500);

   // TimeUntil ts_later is at most 500
   EXPECT_LE(TimeUntil(ts_later), 500);
 }

 TEST(TimeTest, TestTimeDiff64) {
   int64_t ts_diff = 100;
   int64_t ts_earlier = rtc::TimeMillis();
   int64_t ts_later = ts_earlier + ts_diff;
   EXPECT_EQ(ts_diff, rtc::TimeDiff(ts_later, ts_earlier));
   EXPECT_EQ(-ts_diff, rtc::TimeDiff(ts_earlier, ts_later));
 }

 class TimestampWrapAroundHandlerTest : public testing::Test {
  public:
   TimestampWrapAroundHandlerTest() {}

  protected:
   TimestampWrapAroundHandler wraparound_handler_;
 };

 TEST_F(TimestampWrapAroundHandlerTest, Unwrap) {
   // Start value.
   int64_t ts = 2;
   EXPECT_EQ(ts,
             wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

   // Wrap backwards.
   ts = -2;
   EXPECT_EQ(ts,
             wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

   // Forward to 2 again.
   ts = 2;
   EXPECT_EQ(ts,
             wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

   // Max positive skip ahead, until max value (0xffffffff).
   for (uint32_t i = 0; i <= 0xf; ++i) {
     ts = (i << 28) + 0x0fffffff;
     EXPECT_EQ(
         ts, wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));
   }

   // Wrap around.
   ts += 2;
   EXPECT_EQ(ts,
             wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

   // Max wrap backward...
   ts -= 0x0fffffff;
   EXPECT_EQ(ts,
             wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

   // ...and back again.
   ts += 0x0fffffff;
   EXPECT_EQ(ts,
             wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));
 }

 TEST_F(TimestampWrapAroundHandlerTest, NoNegativeStart) {
   int64_t ts = 0xfffffff0;
   EXPECT_EQ(ts,
             wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));
 }

 class TmToSeconds : public testing::Test {
  public:
   TmToSeconds() {
     // Set use of the test RNG to get deterministic expiration timestamp.
     rtc::SetRandomTestMode(true);
   }
   ~TmToSeconds() override {
     // Put it back for the next test.
     rtc::SetRandomTestMode(false);
   }

   void TestTmToSeconds(int times) {
     static char mdays[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
     for (int i = 0; i < times; i++) {

       // First generate something correct and check that TmToSeconds is happy.
       int year = rtc::CreateRandomId() % 400 + 1970;

       bool leap_year = false;
       if (year % 4 == 0)
         leap_year = true;
       if (year % 100 == 0)
         leap_year = false;
       if (year % 400 == 0)
         leap_year = true;

       std::tm tm;
       tm.tm_year = year - 1900;  // std::tm is year 1900 based.
       tm.tm_mon = rtc::CreateRandomId() % 12;
       tm.tm_mday = rtc::CreateRandomId() % mdays[tm.tm_mon] + 1;
       tm.tm_hour = rtc::CreateRandomId() % 24;
       tm.tm_min = rtc::CreateRandomId() % 60;
       tm.tm_sec = rtc::CreateRandomId() % 60;
       int64_t t = rtc::TmToSeconds(tm);
       EXPECT_TRUE(t >= 0);

       // Now damage a random field and check that TmToSeconds is unhappy.
       switch (rtc::CreateRandomId() % 11) {
         case 0:
           tm.tm_year = 1969 - 1900;
           break;
         case 1:
           tm.tm_mon = -1;
           break;
         case 2:
           tm.tm_mon = 12;
           break;
         case 3:
           tm.tm_mday = 0;
           break;
         case 4:
           tm.tm_mday = mdays[tm.tm_mon] + (leap_year && tm.tm_mon == 1) + 1;
           break;
         case 5:
           tm.tm_hour = -1;
           break;
         case 6:
           tm.tm_hour = 24;
           break;
         case 7:
           tm.tm_min = -1;
           break;
         case 8:
           tm.tm_min = 60;
           break;
         case 9:
           tm.tm_sec = -1;
           break;
         case 10:
           tm.tm_sec = 60;
           break;
       }
       EXPECT_EQ(rtc::TmToSeconds(tm), -1);
     }
     // Check consistency with the system gmtime_r.  With time_t, we can only
     // portably test dates until 2038, which is achieved by the % 0x80000000.
     for (int i = 0; i < times; i++) {
       time_t t = rtc::CreateRandomId() % 0x80000000;
 #if defined(WEBRTC_WIN)
       std::tm* tm = std::gmtime(&t);
       EXPECT_TRUE(tm);
       EXPECT_TRUE(rtc::TmToSeconds(*tm) == t);
 #else
       std::tm tm;
       EXPECT_TRUE(gmtime_r(&t, &tm));
       EXPECT_TRUE(rtc::TmToSeconds(tm) == t);
 #endif
     }
   }
 };

 TEST_F(TmToSeconds, TestTmToSeconds) {
   TestTmToSeconds(100000);
 }

 TEST(TimeDelta, FromAndTo) {
   EXPECT_TRUE(TimeDelta::FromSeconds(2) == TimeDelta::FromMilliseconds(2000));
   EXPECT_TRUE(TimeDelta::FromMilliseconds(3) ==
               TimeDelta::FromMicroseconds(3000));
   EXPECT_TRUE(TimeDelta::FromMicroseconds(4) ==
               TimeDelta::FromNanoseconds(4000));
   EXPECT_EQ(13, TimeDelta::FromSeconds(13).ToSeconds());
   EXPECT_EQ(13, TimeDelta::FromMilliseconds(13).ToMilliseconds());
   EXPECT_EQ(13, TimeDelta::FromMicroseconds(13).ToMicroseconds());
   EXPECT_EQ(13, TimeDelta::FromNanoseconds(13).ToNanoseconds());
 }

 TEST(TimeDelta, ComparisonOperators) {
   EXPECT_LT(TimeDelta::FromSeconds(1), TimeDelta::FromSeconds(2));
   EXPECT_EQ(TimeDelta::FromSeconds(3), TimeDelta::FromSeconds(3));
   EXPECT_GT(TimeDelta::FromSeconds(5), TimeDelta::FromSeconds(4));
 }

 TEST(TimeDelta, NumericOperators) {
   double d = 0.5;
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) * d);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) / d);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) *= d);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) /= d);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             d * TimeDelta::FromMilliseconds(1000));

   float f = 0.5;
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) * f);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) / f);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) *= f);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) /= f);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             f * TimeDelta::FromMilliseconds(1000));

   int i = 2;
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) * i);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) / i);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) *= i);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) /= i);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             i * TimeDelta::FromMilliseconds(1000));

   int64_t i64 = 2;
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) * i64);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) / i64);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) *= i64);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) /= i64);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             i64 * TimeDelta::FromMilliseconds(1000));

   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) * 0.5);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) / 0.5);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) *= 0.5);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) /= 0.5);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             0.5 * TimeDelta::FromMilliseconds(1000));

   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) * 2);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) / 2);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             TimeDelta::FromMilliseconds(1000) *= 2);
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
             TimeDelta::FromMilliseconds(1000) /= 2);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
             2 * TimeDelta::FromMilliseconds(1000));
 }

 // Test that all the time functions exposed by TimeUtils get time from the
 // fake clock when it's set.
 TEST(FakeClock, TimeFunctionsUseFakeClock) {
   FakeClock clock;
   SetClockForTesting(&clock);

   clock.SetTimeNanos(987654321);
   EXPECT_EQ(987u, Time32());
   EXPECT_EQ(987, TimeMillis());
   EXPECT_EQ(987654, TimeMicros());
   EXPECT_EQ(987654321, TimeNanos());
   EXPECT_EQ(1000u, TimeAfter(13));

   SetClockForTesting(nullptr);
   // After it's unset, we should get a normal time.
   EXPECT_NE(987, TimeMillis());
 }

 TEST(FakeClock, InitialTime) {
   FakeClock clock;
   EXPECT_EQ(0, clock.TimeNanos());
 }

 TEST(FakeClock, SetTimeNanos) {
   FakeClock clock;
   clock.SetTimeNanos(123);
   EXPECT_EQ(123, clock.TimeNanos());
   clock.SetTimeNanos(456);
   EXPECT_EQ(456, clock.TimeNanos());
 }

 TEST(FakeClock, AdvanceTime) {
   FakeClock clock;
   clock.AdvanceTime(TimeDelta::FromNanoseconds(1111u));
   EXPECT_EQ(1111, clock.TimeNanos());
   clock.AdvanceTime(TimeDelta::FromMicroseconds(2222u));
   EXPECT_EQ(2223111, clock.TimeNanos());
   clock.AdvanceTime(TimeDelta::FromMilliseconds(3333u));
   EXPECT_EQ(3335223111, clock.TimeNanos());
   clock.AdvanceTime(TimeDelta::FromSeconds(4444u));
   EXPECT_EQ(4447335223111, clock.TimeNanos());
 }

 // When the clock is advanced, threads that are waiting in a socket select
 // should wake up and look at the new time. This allows tests using the
 // fake clock to run much faster, if the test is bound by time constraints
 // (such as a test for a STUN ping timeout).
 TEST(FakeClock, SettingTimeWakesThreads) {
   int64_t real_start_time_ms = TimeMillis();

   FakeClock clock;
   SetClockForTesting(&clock);

   Thread worker;
   worker.Start();

   // Post an event that won't be executed for 10 seconds.
   Event message_handler_dispatched(false, false);
   auto functor = [&message_handler_dispatched] {
     message_handler_dispatched.Set();
   };
   FunctorMessageHandler<void, decltype(functor)> handler(functor);
   worker.PostDelayed(RTC_FROM_HERE, 60000, &handler);

   // Wait for a bit for the worker thread to be started and enter its socket
   // select(). Otherwise this test would be trivial since the worker thread
   // would process the event as soon as it was started.
   Thread::Current()->SleepMs(1000);

   // Advance the fake clock, expecting the worker thread to wake up
   // and dispatch the message instantly.
   clock.AdvanceTime(TimeDelta::FromSeconds(60u));
   EXPECT_TRUE(message_handler_dispatched.Wait(0));
   worker.Stop();

   SetClockForTesting(nullptr);

   // The message should have been dispatched long before the 60 seconds fully
   // elapsed (just a sanity check).
   int64_t real_end_time_ms = TimeMillis();
   EXPECT_LT(real_end_time_ms - real_start_time_ms, 10000);
 }

 }  // namespace rtc
	/*
	* Copyright 2004 The WebRTC Project Authors. All rights reserved.
	*
	* Use of this source code is governed by a BSD-style license
	* that can be found in the LICENSE file in the root of the source
	* tree. An additional intellectual property rights grant can be found
	* in the file PATENTS. All contributing project authors may
	* be found in the AUTHORS file in the root of the source tree.
	*/

	#include "webrtc/base/event.h"
	#include "webrtc/base/fakeclock.h"
	#include "webrtc/base/gunit.h"
	#include "webrtc/base/helpers.h"
	#include "webrtc/base/thread.h"
	#include "webrtc/base/timeutils.h"

	namespace rtc {

	TEST(TimeTest, TimeInMs) {
	int64_t ts_earlier = TimeMillis();
	Thread::SleepMs(100);
	int64_t ts_now = TimeMillis();
	// Allow for the thread to wakeup ~20ms early.
	EXPECT_GE(ts_now, ts_earlier + 80);
	// Make sure the Time is not returning in smaller unit like microseconds.
	EXPECT_LT(ts_now, ts_earlier + 1000);
	}

	TEST(TimeTest, Intervals) {
	int64_t ts_earlier = TimeMillis();
	int64_t ts_later = TimeAfter(500);

	// We can't depend on ts_later and ts_earlier to be exactly 500 apart
	// since time elapses between the calls to TimeMillis() and TimeAfter(500)
	EXPECT_LE(500, TimeDiff(ts_later, ts_earlier));
	EXPECT_GE(-500, TimeDiff(ts_earlier, ts_later));

	// Time has elapsed since ts_earlier
	EXPECT_GE(TimeSince(ts_earlier), 0);

	// ts_earlier is earlier than now, so TimeUntil ts_earlier is -ve
	EXPECT_LE(TimeUntil(ts_earlier), 0);

	// ts_later likely hasn't happened yet, so TimeSince could be -ve
	// but within 500
	EXPECT_GE(TimeSince(ts_later), -500);

	// TimeUntil ts_later is at most 500
	EXPECT_LE(TimeUntil(ts_later), 500);
	}

	TEST(TimeTest, TestTimeDiff64) {
	int64_t ts_diff = 100;
	int64_t ts_earlier = rtc::TimeMillis();
	int64_t ts_later = ts_earlier + ts_diff;
	EXPECT_EQ(ts_diff, rtc::TimeDiff(ts_later, ts_earlier));
	EXPECT_EQ(-ts_diff, rtc::TimeDiff(ts_earlier, ts_later));
	}

	class TimestampWrapAroundHandlerTest : public testing::Test {
	public:
	TimestampWrapAroundHandlerTest() {}

	protected:
	TimestampWrapAroundHandler wraparound_handler_;
	};

	TEST_F(TimestampWrapAroundHandlerTest, Unwrap) {
	// Start value.
	int64_t ts = 2;
	EXPECT_EQ(ts,
	wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

	// Wrap backwards.
	ts = -2;
	EXPECT_EQ(ts,
	wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

	// Forward to 2 again.
	ts = 2;
	EXPECT_EQ(ts,
	wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

	// Max positive skip ahead, until max value (0xffffffff).
	for (uint32_t i = 0; i <= 0xf; ++i) {
	ts = (i << 28) + 0x0fffffff;
	EXPECT_EQ(
	ts, wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));
	}

	// Wrap around.
	ts += 2;
	EXPECT_EQ(ts,
	wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

	// Max wrap backward...
	ts -= 0x0fffffff;
	EXPECT_EQ(ts,
	wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));

	// ...and back again.
	ts += 0x0fffffff;
	EXPECT_EQ(ts,
	wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));
	}

	TEST_F(TimestampWrapAroundHandlerTest, NoNegativeStart) {
	int64_t ts = 0xfffffff0;
	EXPECT_EQ(ts,
	wraparound_handler_.Unwrap(static_cast<uint32_t>(ts & 0xffffffff)));
	}

	class TmToSeconds : public testing::Test {
	public:
	TmToSeconds() {
	// Set use of the test RNG to get deterministic expiration timestamp.
	rtc::SetRandomTestMode(true);
	}
	~TmToSeconds() override {
	// Put it back for the next test.
	rtc::SetRandomTestMode(false);
	}

	void TestTmToSeconds(int times) {
	static char mdays[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
	for (int i = 0; i < times; i++) {

	// First generate something correct and check that TmToSeconds is happy.
	int year = rtc::CreateRandomId() % 400 + 1970;

	bool leap_year = false;
	if (year % 4 == 0)
	leap_year = true;
	if (year % 100 == 0)
	leap_year = false;
	if (year % 400 == 0)
	leap_year = true;

	std::tm tm;
	tm.tm_year = year - 1900; // std::tm is year 1900 based.
	tm.tm_mon = rtc::CreateRandomId() % 12;
	tm.tm_mday = rtc::CreateRandomId() % mdays[tm.tm_mon] + 1;
	tm.tm_hour = rtc::CreateRandomId() % 24;
	tm.tm_min = rtc::CreateRandomId() % 60;
	tm.tm_sec = rtc::CreateRandomId() % 60;
	int64_t t = rtc::TmToSeconds(tm);
	EXPECT_TRUE(t >= 0);

	// Now damage a random field and check that TmToSeconds is unhappy.
	switch (rtc::CreateRandomId() % 11) {
	case 0:
	tm.tm_year = 1969 - 1900;
	break;
	case 1:
	tm.tm_mon = -1;
	break;
	case 2:
	tm.tm_mon = 12;
	break;
	case 3:
	tm.tm_mday = 0;
	break;
	case 4:
	tm.tm_mday = mdays[tm.tm_mon] + (leap_year && tm.tm_mon == 1) + 1;
	break;
	case 5:
	tm.tm_hour = -1;
	break;
	case 6:
	tm.tm_hour = 24;
	break;
	case 7:
	tm.tm_min = -1;
	break;
	case 8:
	tm.tm_min = 60;
	break;
	case 9:
	tm.tm_sec = -1;
	break;
	case 10:
	tm.tm_sec = 60;
	break;
	}
	EXPECT_EQ(rtc::TmToSeconds(tm), -1);
	}
	// Check consistency with the system gmtime_r. With time_t, we can only
	// portably test dates until 2038, which is achieved by the % 0x80000000.
	for (int i = 0; i < times; i++) {
	time_t t = rtc::CreateRandomId() % 0x80000000;
	#if defined(WEBRTC_WIN)
	std::tm* tm = std::gmtime(&t);
	EXPECT_TRUE(tm);
	EXPECT_TRUE(rtc::TmToSeconds(*tm) == t);
	#else
	std::tm tm;
	EXPECT_TRUE(gmtime_r(&t, &tm));
	EXPECT_TRUE(rtc::TmToSeconds(tm) == t);
	#endif
	}
	}
	};

	TEST_F(TmToSeconds, TestTmToSeconds) {
	TestTmToSeconds(100000);
	}

	TEST(TimeDelta, FromAndTo) {
	EXPECT_TRUE(TimeDelta::FromSeconds(2) == TimeDelta::FromMilliseconds(2000));
	EXPECT_TRUE(TimeDelta::FromMilliseconds(3) ==
	TimeDelta::FromMicroseconds(3000));
	EXPECT_TRUE(TimeDelta::FromMicroseconds(4) ==
	TimeDelta::FromNanoseconds(4000));
	EXPECT_EQ(13, TimeDelta::FromSeconds(13).ToSeconds());
	EXPECT_EQ(13, TimeDelta::FromMilliseconds(13).ToMilliseconds());
	EXPECT_EQ(13, TimeDelta::FromMicroseconds(13).ToMicroseconds());
	EXPECT_EQ(13, TimeDelta::FromNanoseconds(13).ToNanoseconds());
	}

	TEST(TimeDelta, ComparisonOperators) {
	EXPECT_LT(TimeDelta::FromSeconds(1), TimeDelta::FromSeconds(2));
	EXPECT_EQ(TimeDelta::FromSeconds(3), TimeDelta::FromSeconds(3));
	EXPECT_GT(TimeDelta::FromSeconds(5), TimeDelta::FromSeconds(4));
	}

	TEST(TimeDelta, NumericOperators) {
	double d = 0.5;
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) * d);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) / d);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) *= d);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) /= d);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	d * TimeDelta::FromMilliseconds(1000));

	float f = 0.5;
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) * f);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) / f);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) *= f);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) /= f);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	f * TimeDelta::FromMilliseconds(1000));

	int i = 2;
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) * i);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) / i);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) *= i);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) /= i);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	i * TimeDelta::FromMilliseconds(1000));

	int64_t i64 = 2;
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) * i64);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) / i64);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) *= i64);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) /= i64);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	i64 * TimeDelta::FromMilliseconds(1000));

	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) * 0.5);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) / 0.5);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) *= 0.5);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) /= 0.5);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	0.5 * TimeDelta::FromMilliseconds(1000));

	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) * 2);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) / 2);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	TimeDelta::FromMilliseconds(1000) *= 2);
	EXPECT_EQ(TimeDelta::FromMilliseconds(500),
	TimeDelta::FromMilliseconds(1000) /= 2);
	EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
	2 * TimeDelta::FromMilliseconds(1000));
	}

	// Test that all the time functions exposed by TimeUtils get time from the
	// fake clock when it's set.
	TEST(FakeClock, TimeFunctionsUseFakeClock) {
	FakeClock clock;
	SetClockForTesting(&clock);

	clock.SetTimeNanos(987654321);
	EXPECT_EQ(987u, Time32());
	EXPECT_EQ(987, TimeMillis());
	EXPECT_EQ(987654, TimeMicros());
	EXPECT_EQ(987654321, TimeNanos());
	EXPECT_EQ(1000u, TimeAfter(13));

	SetClockForTesting(nullptr);
	// After it's unset, we should get a normal time.
	EXPECT_NE(987, TimeMillis());
	}

	TEST(FakeClock, InitialTime) {
	FakeClock clock;
	EXPECT_EQ(0, clock.TimeNanos());
	}

	TEST(FakeClock, SetTimeNanos) {
	FakeClock clock;
	clock.SetTimeNanos(123);
	EXPECT_EQ(123, clock.TimeNanos());
	clock.SetTimeNanos(456);
	EXPECT_EQ(456, clock.TimeNanos());
	}

	TEST(FakeClock, AdvanceTime) {
	FakeClock clock;
	clock.AdvanceTime(TimeDelta::FromNanoseconds(1111u));
	EXPECT_EQ(1111, clock.TimeNanos());
	clock.AdvanceTime(TimeDelta::FromMicroseconds(2222u));
	EXPECT_EQ(2223111, clock.TimeNanos());
	clock.AdvanceTime(TimeDelta::FromMilliseconds(3333u));
	EXPECT_EQ(3335223111, clock.TimeNanos());
	clock.AdvanceTime(TimeDelta::FromSeconds(4444u));
	EXPECT_EQ(4447335223111, clock.TimeNanos());
	}

	// When the clock is advanced, threads that are waiting in a socket select
	// should wake up and look at the new time. This allows tests using the
	// fake clock to run much faster, if the test is bound by time constraints
	// (such as a test for a STUN ping timeout).
	TEST(FakeClock, SettingTimeWakesThreads) {
	int64_t real_start_time_ms = TimeMillis();

	FakeClock clock;
	SetClockForTesting(&clock);

	Thread worker;
	worker.Start();

	// Post an event that won't be executed for 10 seconds.
	Event message_handler_dispatched(false, false);
	auto functor = [&message_handler_dispatched] {
	message_handler_dispatched.Set();
	};
	FunctorMessageHandler<void, decltype(functor)> handler(functor);
	worker.PostDelayed(RTC_FROM_HERE, 60000, &handler);

	// Wait for a bit for the worker thread to be started and enter its socket
	// select(). Otherwise this test would be trivial since the worker thread
	// would process the event as soon as it was started.
	Thread::Current()->SleepMs(1000);

	// Advance the fake clock, expecting the worker thread to wake up
	// and dispatch the message instantly.
	clock.AdvanceTime(TimeDelta::FromSeconds(60u));
	EXPECT_TRUE(message_handler_dispatched.Wait(0));
	worker.Stop();

	SetClockForTesting(nullptr);

	// The message should have been dispatched long before the 60 seconds fully
	// elapsed (just a sanity check).
	int64_t real_end_time_ms = TimeMillis();
	EXPECT_LT(real_end_time_ms - real_start_time_ms, 10000);
	}

	} // namespace rtc