cc: Send all begin frames using a PostTask.

cc/scheduler/delay_based_time_source_unittest.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/scheduler/delay_based_time_source.h"
 
 #include <stdint.h>
 
 #include "base/test/test_simple_task_runner.h"
 #include "cc/test/scheduler_test_common.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace cc {
 namespace {
 
 base::TimeDelta Interval() {
   return base::TimeDelta::FromMicroseconds(base::Time::kMicrosecondsPerSecond /
                                            60);
 }
 
 TEST(DelayBasedTimeSourceTest, TaskPostedAndTickCalled) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   EXPECT_TRUE(timer->Active());
   EXPECT_TRUE(task_runner->HasPendingTask());
 
-  timer->SetNow(timer->Now() + base::TimeDelta::FromMilliseconds(16));
+  now_src.SetNowTicks(now_src.NowTicks() +
+                      base::TimeDelta::FromMilliseconds(16));
   task_runner->RunPendingTasks();
   EXPECT_TRUE(timer->Active());
   EXPECT_TRUE(client.TickCalled());
 }
 
 TEST(DelayBasedTimeSourceTest, TickNotCalledWithTaskPosted) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   EXPECT_TRUE(task_runner->HasPendingTask());
   timer->SetActive(false);
   task_runner->RunPendingTasks();
   EXPECT_FALSE(client.TickCalled());
 }
 
 TEST(DelayBasedTimeSourceTest, StartTwiceEnqueuesOneTask) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   EXPECT_TRUE(task_runner->HasPendingTask());
   task_runner->ClearPendingTasks();
   timer->SetActive(true);
   EXPECT_FALSE(task_runner->HasPendingTask());
 }
 
 TEST(DelayBasedTimeSourceTest, StartWhenRunningDoesntTick) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   EXPECT_TRUE(task_runner->HasPendingTask());
   task_runner->RunPendingTasks();
   task_runner->ClearPendingTasks();
   timer->SetActive(true);
   EXPECT_FALSE(task_runner->HasPendingTask());
 }
 
 // At 60Hz, when the tick returns at exactly the requested next time, make sure
 // a 16ms next delay is posted.
 TEST(DelayBasedTimeSourceTest, NextDelaySaneWhenExactlyOnRequestedTime) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   // Run the first tick.
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
-  timer->SetNow(timer->Now() + Interval());
+  now_src.SetNowTicks(now_src.NowTicks() + Interval());
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 }
 
 // At 60Hz, when the tick returns at slightly after the requested next time,
 // make sure a 16ms next delay is posted.
 TEST(DelayBasedTimeSourceTest, NextDelaySaneWhenSlightlyAfterRequestedTime) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   // Run the first tick.
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
-  timer->SetNow(timer->Now() + Interval() +
-                base::TimeDelta::FromMicroseconds(1));
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() +
+                      base::TimeDelta::FromMicroseconds(1));
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 }
 
 // At 60Hz, when the tick returns at exactly 2*interval after the requested next
 // time, make sure we don't tick unnecessarily.
 TEST(DelayBasedTimeSourceTest,
      NextDelaySaneWhenExactlyTwiceAfterRequestedTime) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   // Run the first tick.
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
-  timer->SetNow(timer->Now() + 2 * Interval());
+  now_src.SetNowTicks(now_src.NowTicks() + 2 * Interval());
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 }
 
 // At 60Hz, when the tick returns at 2*interval and a bit after the requested
 // next time, make sure a 16ms next delay is posted.
 TEST(DelayBasedTimeSourceTest,
      NextDelaySaneWhenSlightlyAfterTwiceRequestedTime) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   // Run the first tick.
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
-  timer->SetNow(timer->Now() + 2 * Interval() +
-                base::TimeDelta::FromMicroseconds(1));
+  now_src.SetNowTicks(now_src.NowTicks() + 2 * Interval() +
+                      base::TimeDelta::FromMicroseconds(1));
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 }
 
 // At 60Hz, when the tick returns halfway to the next frame time, make sure
 // a correct next delay value is posted.
 TEST(DelayBasedTimeSourceTest, NextDelaySaneWhenHalfAfterRequestedTime) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
   // Run the first tick.
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
-  timer->SetNow(timer->Now() + Interval() +
-                base::TimeDelta::FromMilliseconds(8));
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() +
+                      base::TimeDelta::FromMilliseconds(8));
   task_runner->RunPendingTasks();
 
   EXPECT_EQ(8, task_runner->NextPendingTaskDelay().InMilliseconds());
 }
 
 TEST(DelayBasedTimeSourceTest, JitteryRuntimeWithFutureTimebases) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
 
   // Run the first tick.
   task_runner->RunPendingTasks();
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
-  base::TimeTicks future_timebase = timer->Now() + Interval() * 10;
+  base::TimeTicks future_timebase = now_src.NowTicks() + Interval() * 10;
 
   // 1ms jitter
   base::TimeDelta jitter1 = base::TimeDelta::FromMilliseconds(1);
 
   // Tick with +1ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() + jitter1);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() + jitter1);
   task_runner->RunPendingTasks();
   EXPECT_EQ(15, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with 0ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() - jitter1);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() - jitter1);
   task_runner->RunPendingTasks();
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with -1ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() - jitter1);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() - jitter1);
   task_runner->RunPendingTasks();
   EXPECT_EQ(1, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with 0ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() + jitter1);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() + jitter1);
   task_runner->RunPendingTasks();
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // 8 ms jitter
   base::TimeDelta jitter8 = base::TimeDelta::FromMilliseconds(8);
 
   // Tick with +8ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() + jitter8);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() + jitter8);
   task_runner->RunPendingTasks();
   EXPECT_EQ(8, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with 0ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() - jitter8);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() - jitter8);
   task_runner->RunPendingTasks();
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with -8ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() - jitter8);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() - jitter8);
   task_runner->RunPendingTasks();
   EXPECT_EQ(8, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with 0ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() + jitter8);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() + jitter8);
   task_runner->RunPendingTasks();
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // 15 ms jitter
-  base::TimeDelta jitter15  = base::TimeDelta::FromMilliseconds(15);
+  base::TimeDelta jitter15 = base::TimeDelta::FromMilliseconds(15);
 
   // Tick with +15ms jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() + jitter15);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() + jitter15);
   task_runner->RunPendingTasks();
   EXPECT_EQ(1, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with 0ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() - jitter15);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() - jitter15);
   task_runner->RunPendingTasks();
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with -15ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() - jitter15);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() - jitter15);
   task_runner->RunPendingTasks();
   EXPECT_EQ(15, task_runner->NextPendingTaskDelay().InMilliseconds());
 
   // Tick with 0ms of jitter
   future_timebase += Interval();
   timer->SetTimebaseAndInterval(future_timebase, Interval());
-  timer->SetNow(timer->Now() + Interval() + jitter15);
+  now_src.SetNowTicks(now_src.NowTicks() + Interval() + jitter15);
   task_runner->RunPendingTasks();
   EXPECT_EQ(16, task_runner->NextPendingTaskDelay().InMilliseconds());
 }
 
 TEST(DelayBasedTimeSourceTest, AchievesTargetRateWithNoNoise) {
   int num_iterations = 10;
 
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);
 
   double total_frame_time = 0.0;
   for (int i = 0; i < num_iterations; ++i) {
     int64_t delay_ms = task_runner->NextPendingTaskDelay().InMilliseconds();
 
     // accumulate the "delay"
     total_frame_time += delay_ms / 1000.0;
 
     // Run the callback exactly when asked
-    timer->SetNow(timer->Now() + base::TimeDelta::FromMilliseconds(delay_ms));
+    now_src.SetNowTicks(now_src.NowTicks() +
+                        base::TimeDelta::FromMilliseconds(delay_ms));
     task_runner->RunPendingTasks();
   }
   double average_interval =
       total_frame_time / static_cast<double>(num_iterations);
   EXPECT_NEAR(1.0 / 60.0, average_interval, 0.1);
 }
 
 TEST(DelayBasedTimeSourceTest, TestDeactivateWhilePending) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
   timer->SetActive(true);  // Should post a task.
   timer->SetActive(false);
   timer = NULL;
   // Should run the posted task without crashing.
   EXPECT_TRUE(task_runner->HasPendingTask());
   task_runner->RunPendingTasks();
 }
 
 TEST(DelayBasedTimeSourceTest, TestDeactivateAndReactivateBeforeNextTickTime) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
 
   // Should run the activate task, and pick up a new timebase.
   timer->SetActive(true);
   task_runner->RunPendingTasks();
 
   // Stop the timer
   timer->SetActive(false);
 
   // Task will be pending anyway, run it
   task_runner->RunPendingTasks();
 
   // Start the timer again, but before the next tick time the timer previously
   // planned on using. That same tick time should still be targeted.
-  timer->SetNow(timer->Now() + base::TimeDelta::FromMilliseconds(4));
+  now_src.SetNowTicks(now_src.NowTicks() +
+                      base::TimeDelta::FromMilliseconds(4));
   timer->SetActive(true);
   EXPECT_EQ(12, task_runner->NextPendingTaskDelay().InMilliseconds());
 }
 
 TEST(DelayBasedTimeSourceTest, TestDeactivateAndReactivateAfterNextTickTime) {
   scoped_refptr<base::TestSimpleTaskRunner> task_runner =
       new base::TestSimpleTaskRunner;
   FakeDelayBasedTimeSourceClient client;
-  std::unique_ptr<FakeDelayBasedTimeSource> timer(
-      new FakeDelayBasedTimeSource(task_runner.get()));
+  base::SimpleTestTickClock now_src;
+  std::unique_ptr<DelayBasedTimeSource> timer(
+      new DelayBasedTimeSource(task_runner.get(), &now_src));
   timer->SetClient(&client);
   timer->SetTimebaseAndInterval(base::TimeTicks(), Interval());
 
   // Should run the activate task, and pick up a new timebase.
   timer->SetActive(true);
   task_runner->RunPendingTasks();
 
   // Stop the timer.
   timer->SetActive(false);
 
   // Task will be pending anyway, run it.
   task_runner->RunPendingTasks();
 
   // Start the timer again, but before the next tick time the timer previously
   // planned on using. That same tick time should still be targeted.
-  timer->SetNow(timer->Now() + base::TimeDelta::FromMilliseconds(20));
+  now_src.SetNowTicks(now_src.NowTicks() +
+                      base::TimeDelta::FromMilliseconds(20));
   timer->SetActive(true);
   EXPECT_EQ(13, task_runner->NextPendingTaskDelay().InMilliseconds());
 }
 
 }  // namespace
 }  // namespace cc