Fixing and enhancing OrderedSimpleTaskRunner to allow 100% deterministic tests.

cc/test/ordered_simple_task_runner.h

 // Copyright 2014 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.
 
 #ifndef CC_TEST_ORDERED_SIMPLE_TASK_RUNNER_H_
 #define CC_TEST_ORDERED_SIMPLE_TASK_RUNNER_H_
 
+#include <deque>
+
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
+#include "base/debug/trace_event.h"
+#include "base/logging.h"
 #include "base/test/test_simple_task_runner.h"
 
 namespace cc {
 
 // This runs pending tasks based on task's post_time + delay.
 // We should not execute a delayed task sooner than some of the queued tasks
 // which don't have a delay even though it is queued early.
 class OrderedSimpleTaskRunner : public base::TestSimpleTaskRunner {
  public:
-  OrderedSimpleTaskRunner();
+  explicit OrderedSimpleTaskRunner(bool advance_now = true);

[Sami, 2014/08/19 18:45:04]

No default arguments in chromium please :P

[mithro-old, 2014/08/21 17:39:18]

How does one do this otherwise?

[Sami, 2014/08/19 18:45:04]

// base::TestSimpleTaskRunner implementation:

[mithro-old, 2014/08/21 17:39:18]

Done.

+  virtual bool PostDelayedTask(const tracked_objects::Location& from_here,
+                               const base::Closure& task,
+                               base::TimeDelta delay) OVERRIDE;
+  virtual bool PostNonNestableDelayedTask(

[Sami, 2014/08/19 18:45:04]

Just curious: do we ever post non-nestable tasks from the compositor? If not, we
could probably simplify this a bit and just make this a NOTREACHED().

[mithro-old, 2014/08/21 17:39:19]

No idea. I do think this task runner could possibly be suitable to end up in
base/ once we prove its usefulness? It would be bad for it to be reimplemented
many times (because it's been surprisingly hard to actually get right).

+      const tracked_objects::Location& from_here,
+      const base::Closure& task,
+      base::TimeDelta delay) OVERRIDE;
   virtual void RunPendingTasks() OVERRIDE;
 
+  base::TimeTicks Now() const;

[brianderson, 2014/08/20 20:04:31]

protected not public.

[mithro-old, 2014/08/21 17:39:19]

Done.

+  base::TimeDelta DelayToNextPendingTask();
+  void SetAutoAdvanceNowToPendingTasks(bool advance_now);
+  void SetNow(base::TimeTicks time);

[brianderson, 2014/08/20 20:04:31]

Remove this.

[mithro-old, 2014/08/21 17:39:19]

Done.

+
+  scoped_refptr<base::debug::ConvertableToTraceFormat> AsValue() const;
+
  protected:
   virtual ~OrderedSimpleTaskRunner();
 
+  static void SortTasks(std::deque<base::TestPendingTask>* tasks);
+
  private:
+  bool advance_now_;
+  base::TimeTicks now_;
+  bool inside_run_pending_tasks_;
+
+  friend void PrintTo(const OrderedSimpleTaskRunner& t, ::std::ostream* os);
+
   DISALLOW_COPY_AND_ASSIGN(OrderedSimpleTaskRunner);
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_ORDERED_SIMPLE_TASK_RUNNER_H_