Add desktop engagement metrics.

chrome/browser/metrics/desktop_engagement/desktop_engagement_service_unittest.cc

Index: chrome/browser/metrics/desktop_engagement/desktop_engagement_service_unittest.cc
diff --git a/chrome/browser/metrics/desktop_engagement/desktop_engagement_service_unittest.cc b/chrome/browser/metrics/desktop_engagement/desktop_engagement_service_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..a0a23dc62ad711b4c8d10e000e08f645c5dd2db7
--- /dev/null
+++ b/chrome/browser/metrics/desktop_engagement/desktop_engagement_service_unittest.cc
@@ -0,0 +1,149 @@
+// 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.
+
+#include "chrome/browser/metrics/desktop_engagement/desktop_engagement_service.h"
+
+#include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
+#include "base/test/histogram_tester.h"
+#include "base/test/test_mock_time_task_runner.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+// Mock class for |DesktopEngagementService| for testing.
+class MockDesktopEngagementService : public DesktopEngagementService {
+ public:
+  bool is_visible() { return is_visible_; }
+  bool in_session() { return in_session_; }
+  bool is_audio_playing() { return is_audio_playing_; }
+  bool is_timeout() { return time_out_; }
+
+  void SetInactivityTimeout(int seconds) {
+    inactivity_timeout_ = base::TimeDelta::FromSeconds(seconds);
+  }
+
+ protected:
+  void OnTimerFired() override {
+    DesktopEngagementService::OnTimerFired();
+    time_out_ = true;
+  }
+
+ private:
+  bool time_out_ = false;
+};
+
+TEST(DesktopEngagementServiceTest, TestVisibility) {
+  base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+  base::HistogramTester histogram_tester;
+
+  MockDesktopEngagementService instance;
+
+  // The browser becomes visible but it shouldn't start the session.
+  instance.OnVisibilityChanged(true);
+  EXPECT_FALSE(instance.in_session());
+  EXPECT_TRUE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 0);
+
+  instance.OnUserEvent();
+  EXPECT_TRUE(instance.in_session());
+  EXPECT_TRUE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 0);
+
+  // Even if there is a recent user event visibility change should end the
+  // session.
+  instance.OnUserEvent();
+  instance.OnUserEvent();
+  instance.OnVisibilityChanged(false);
+  EXPECT_FALSE(instance.in_session());
+  EXPECT_FALSE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 1);
+
+  // For the second time only visibility change should start the session.
+  instance.OnVisibilityChanged(true);
+  EXPECT_TRUE(instance.in_session());
+  EXPECT_TRUE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 1);
+  instance.OnVisibilityChanged(false);
+  EXPECT_FALSE(instance.in_session());
+  EXPECT_FALSE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 2);
+}
+
+TEST(DesktopEngagementServiceTest, TestUserEvent) {
+  base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+  base::HistogramTester histogram_tester;
+
+  MockDesktopEngagementService instance;
+  instance.SetInactivityTimeout(1);
+
+  EXPECT_FALSE(instance.in_session());
+  EXPECT_FALSE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 0);
+
+  // User event doesn't go through if nothing is visible.
+  instance.OnUserEvent();
+  EXPECT_FALSE(instance.in_session());
+  EXPECT_FALSE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 0);
+
+  instance.OnVisibilityChanged(true);
+  instance.OnUserEvent();
+  EXPECT_TRUE(instance.in_session());
+  EXPECT_TRUE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 0);
+
+  // Wait until the session expires.
+  while (!instance.is_timeout()) {
+    base::RunLoop().RunUntilIdle();
+  }
+
+  EXPECT_FALSE(instance.in_session());
+  EXPECT_TRUE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 1);
+}
+
+TEST(DesktopEngagementServiceTest, TestAudioEvent) {
+  base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+  base::HistogramTester histogram_tester;
+
+  MockDesktopEngagementService instance;
+  instance.SetInactivityTimeout(1);
+
+  instance.OnVisibilityChanged(true);
+  instance.OnAudioStart();
+  EXPECT_TRUE(instance.in_session());
+  EXPECT_TRUE(instance.is_visible());
+  EXPECT_TRUE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 0);
+
+  instance.OnVisibilityChanged(false);
+  EXPECT_TRUE(instance.in_session());
+  EXPECT_FALSE(instance.is_visible());
+  EXPECT_TRUE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 0);
+
+  instance.OnAudioEnd();
+  EXPECT_TRUE(instance.in_session());
+  EXPECT_FALSE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 0);
+
+  // Wait until the session expires.
+  while (!instance.is_timeout()) {
+    base::RunLoop().RunUntilIdle();
+  }
+
+  EXPECT_FALSE(instance.in_session());
+  EXPECT_FALSE(instance.is_visible());
+  EXPECT_FALSE(instance.is_audio_playing());
+  histogram_tester.ExpectTotalCount("Session.TotalDuration", 1);
+}