Provide simple wrappers for base/time types in WTF

third_party/WebKit/Source/wtf/Time.h

+// Copyright 2016 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 WTF_Time_h
+#define WTF_Time_h
+
+#include "base/time/time.h"
+#include "wtf/CurrentTime.h"
+
+namespace WTF {
+// Provides thin wrappers around the following basic time types from
+// base/time package:
+//
+//  - WTF::TimeDelta is an alias for base::TimeDelta and represents a duration
+//    of time.
+//  - WTF::TimeTicks wraps base::TimeTicks and represents a monotonic time
+//    value.
+//  - WTF::Time wraps base::Time and represents a wall time value.
+//
+// For usage guideline please see the documentation in base/time/time.h
+
+using TimeDelta = base::TimeDelta;
+
+namespace internal {
+
+template <class WrappedTimeType>
+class TimeWrapper {
+ public:
+  TimeWrapper() {}
+
+  bool isNull() const { return m_value.is_null(); }
+
+  static TimeWrapper Now() {
+    if (WTF::getTimeFunctionForTesting()) {
+      double seconds = (WTF::getTimeFunctionForTesting())();
+      return TimeWrapper() + TimeDelta::FromSecondsD(seconds);
+    }
+    return TimeWrapper(WrappedTimeType::Now());
+  }
+
+  int64_t ToInternalValueForTesting() const {
+    return m_value.ToInternalValue();
+  }
+
+  TimeWrapper& operator=(TimeWrapper other) {
+    m_value = other.m_value;
+    return *this;
+  }
+
+  TimeDelta operator-(TimeWrapper other) const {
+    return m_value - other.m_value;
+  }
+
+  TimeWrapper operator+(TimeDelta delta) const {
+    return TimeWrapper(m_value + delta);
+  }
+  TimeWrapper operator-(TimeDelta delta) const {
+    return TimeWrapper(m_value - delta);
+  }
+
+  TimeWrapper& operator+=(TimeDelta delta) {
+    m_value += delta;
+    return *this;
+  }
+  TimeWrapper& operator-=(TimeDelta delta) {
+    m_value -= delta;
+    return *this;
+  }
+
+  bool operator==(TimeWrapper other) const { return m_value == other.m_value; }
+  bool operator!=(TimeWrapper other) const { return m_value != other.m_value; }
+  bool operator<(TimeWrapper other) const { return m_value < other.m_value; }
+  bool operator<=(TimeWrapper other) const { return m_value <= other.m_value; }
+  bool operator>(TimeWrapper other) const { return m_value > other.m_value; }
+  bool operator>=(TimeWrapper other) const { return m_value >= other.m_value; }
+
+ private:
+  WrappedTimeType m_value;
+  TimeWrapper(WrappedTimeType value) : m_value(value) {}
+};
+
+}  // namespace internal
+
+using Time = internal::TimeWrapper<base::Time>;
+using TimeTicks = internal::TimeWrapper<base::TimeTicks>;
+
+}  // namespace WTF
+
+using WTF::Time;
+using WTF::TimeDelta;
+using WTF::TimeTicks;
+
+#endif  // Time_h