blob: 8f121bab75cb4acba85aff745847e4c2a8c47615 [file] [log] [blame]
// Copyright 2018 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 <memory>
#include "base/time/time.h"
#include "base/time/time_override.h"
namespace base {
// Override the return value of Time::Now(), Time::NowFromSystemTime(),
// TimeTicks::Now(), and ThreadTicks::Now() through a simple advanceable clock.
// This utility is intended to support tests that:
// - Depend on large existing codebases that call TimeXYZ::Now() directly or
// - Have no ability to inject a TickClock into the code getting the time
// (e.g. integration tests in which a TickClock would be several layers
// removed from the test code)
// For new unit tests, developers are highly encouraged to structure new code
// around a dependency injected base::Clock, base::TickClock, etc. to be able
// to supply a mock time in tests without a global override.
// NOTE: ScopedMockClockOverride should be created while single-threaded and
// before the first call to Now() to avoid threading issues and inconsistencies
// in returned values. Nested overrides are not allowed.
class ScopedMockClockOverride {
ScopedMockClockOverride(const ScopedMockClockOverride&) = delete;
ScopedMockClockOverride& operator=(const ScopedMockClockOverride&) = delete;
static Time Now();
static TimeTicks NowTicks();
static ThreadTicks NowThreadTicks();
void Advance(TimeDelta delta);
std::unique_ptr<base::subtle::ScopedTimeClockOverrides> time_clock_overrides_;
TimeDelta offset_;
static ScopedMockClockOverride* scoped_mock_clock_;
} // namespace base