Fixing and enhancing OrderedSimpleTaskRunner to allow 100% deterministic tests.

cc/test/test_now_source.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_TEST_NOW_SOURCE_H_
+#define CC_TEST_TEST_NOW_SOURCE_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/debug/trace_event.h"
+#include "base/debug/trace_event_argument.h"
+#include "base/logging.h"
+
+namespace cc {
+
+class TestNowSource : public base::RefCounted<TestNowSource> {
+ public:
+  static scoped_refptr<TestNowSource> Create();
+  static scoped_refptr<TestNowSource> Create(int64_t initial);
+  static scoped_refptr<TestNowSource> Create(base::TimeTicks initial);
+
+  virtual void Reset();
+  virtual base::TimeTicks Now() const;
+  virtual void SetNow(base::TimeTicks time);
+  virtual void AdvanceNow(base::TimeDelta period);
+
+  // Convenience functions to make it the now source easier to use in unit
+  // tests.
+  void AdvanceNowMicroseconds(int64_t period_in_microseconds);
+  void SetNowMicroseconds(int64_t time_in_microseconds);
+
+  static const base::TimeTicks kAbsoluteMaxNow;
+
+  // Tracing functions
+  scoped_refptr<base::debug::ConvertableToTraceFormat> AsValue() const;
+  void AsValueInto(base::debug::TracedValue* state) const;
+  std::string ToString() const;
+
+ protected:
+  TestNowSource();
+  explicit TestNowSource(int64_t initial);
+  explicit TestNowSource(base::TimeTicks initial);
+
+  base::TimeTicks initial_;
+  base::TimeTicks now_;
+
+ private:
+  friend class base::RefCounted<TestNowSource>;
+  virtual ~TestNowSource();
+};
+
+// gtest pretty printing functions
+void PrintTo(const scoped_refptr<TestNowSource>& src, ::std::ostream* os);
+::std::ostream& operator<<(::std::ostream& os,
+                           const scoped_refptr<TestNowSource>& src);
+
+}  // namespace cc
+
+#endif  // CC_TEST_TEST_NOW_SOURCE_H_