chromium/cc/metrics/average_lag_tracking_manager_unittest.cc

// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "cc/metrics/average_lag_tracking_manager.h"

#include <algorithm>
#include <memory>

#include "base/test/metrics/histogram_tester.h"
#include "components/viz/common/frame_timing_details.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace cc {
namespace {

Bucket;
ElementsAre;
IsEmpty;

// Helper for TimeTicks usage
base::TimeTicks MillisecondsToTimeTicks(int t_ms) { … }

// Helper function returning a successful `FrameTimingDetails` for use in
// `DidPresentCompositorFrame()`.
viz::FrameTimingDetails PrepareFrameDetails(base::TimeTicks swap_time,
                                            base::TimeTicks presentation_time) { … }

// Helper function returning a failed `FrameTimingDetails` for use in
// `DidPresentCompositorFrame()`.
viz::FrameTimingDetails PrepareFailedFrameDetails() { … }

class AverageLagTrackingManagerTest : public testing::Test { … };

// Simulate a simple situation that generates events at every 10ms starting at
// t=15ms and swaps frames at every 10ms, too, starting at t=20ms. Then tests
// that we record one UMA for ScrollUpdate in one second. Tests usage of
// `CollectScrollEventAtFrame()` (1 event per collection).
TEST_F(AverageLagTrackingManagerTest, OneSecondInterval) { … }

// This test creates 3 frames in order to check the submission of ScrollBegin
// and ScrollUpdate events sent using `CollectScrollEventsAtFrame()` (multiple
// events per collection)
TEST_F(AverageLagTrackingManagerTest, MultipleEventsInSameFrame) { … }

// Tests that if failed presentations arrive out-of-order, they don't mark
// previous pending frames as failed since they can still end up in a
// successful presentation.
TEST_F(AverageLagTrackingManagerTest, OutOfOrderPresentationFeedback) { … }

}  // namespace
}  // namespace cc