[Media>UI] Apply throttling if the notification is updated too frequently

chrome/android/junit/src/org/chromium/chrome/browser/media/ui/MediaNotificationManagerThrottlerTest.java

Index: chrome/android/junit/src/org/chromium/chrome/browser/media/ui/MediaNotificationManagerThrottlerTest.java
diff --git a/chrome/android/junit/src/org/chromium/chrome/browser/media/ui/MediaNotificationManagerThrottlerTest.java b/chrome/android/junit/src/org/chromium/chrome/browser/media/ui/MediaNotificationManagerThrottlerTest.java
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index 0000000000000000000000000000000000000000..72e339871e924abeaad99f7dea8c18a26307dc49
--- /dev/null
+++ b/chrome/android/junit/src/org/chromium/chrome/browser/media/ui/MediaNotificationManagerThrottlerTest.java
@@ -0,0 +1,199 @@
+// Copyright 2017 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.
+
+package org.chromium.chrome.browser.media.ui;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertSame;
+import static org.mockito.Mockito.any;
+import static org.mockito.Mockito.clearInvocations;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.verify;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.annotation.Config;
+
+import org.chromium.base.BaseChromiumApplication;
+import org.chromium.testing.local.LocalRobolectricTestRunner;
+
+/**
+ * JUnit tests for checking {@link MediaNotificationManager} throttles notification updates
+ * correctly.
+ */
+@RunWith(LocalRobolectricTestRunner.class)
+@Config(manifest = Config.NONE, application = BaseChromiumApplication.class,
+        shadows = {MediaNotificationTestShadowResources.class})
+public class MediaNotificationManagerThrottlerTest extends MediaNotificationManagerTestBase {
+    private static final int THROTTLE_MILLIS = MediaNotificationManager.Throttler.THROTTLE_MILLIS;
+
+    @Before
+    @Override
+    public void setUp() {
+        super.setUp();
+        getManager().mThrottler = spy(new MediaNotificationManager.Throttler(getManager()));
+    }
+
+    @Test
+    public void testEmptyState() {
+        assertNull(getThrottler().mTask);
+        assertNull(getThrottler().mLastPendingInfo);
+    }
+
+    @Test
+    public void testFirstNotificationIsUnthrottled() {
+        MediaNotificationInfo info = mMediaNotificationInfoBuilder.build();
+        getThrottler().queueNotification(info);
+
+        // Verify the notification is shown immediately
+        verify(getThrottler()).showNotificationImmediately(info);
+        verify(getManager()).showNotification(info);
+
+        // Verify entering the throttled state.
+        assertNotNull(getThrottler().mTask);
+        assertNull(getThrottler().mLastPendingInfo);
+    }
+
+    @Test
+    public void testDelayedTaskFiresWithNoQueuedNotification() {
+        MediaNotificationInfo info = mMediaNotificationInfoBuilder.build();
+        getThrottler().queueNotification(info);
+        clearInvocations(getThrottler());
+
+        // When the task fires while no notification info is queued in throttled state, the
+        // throttler enters unthrottled state.
+        advanceTimeByMillis(THROTTLE_MILLIS);
+        verify(getThrottler(), never()).showNotificationImmediately(info);
+        assertNull(getThrottler().mTask);
+    }
+
+    @Test
+    public void testDelayedTaskFiresWithQueuedNotification() {
+        mMediaNotificationInfoBuilder.setPaused(false);
+        MediaNotificationInfo info1 = mMediaNotificationInfoBuilder.build();
+        mMediaNotificationInfoBuilder.setPaused(true);
+        MediaNotificationInfo info2 = mMediaNotificationInfoBuilder.build();
+
+        getThrottler().queueNotification(info1);
+        getThrottler().queueNotification(info2);
+
+        // In throttled state, queueing a notification info will only update the queued notification
+        // info.
+        verify(getThrottler()).showNotificationImmediately(info1);
+        verify(getThrottler(), never()).showNotificationImmediately(info2);
+        assertNotNull(getThrottler().mTask);
+        assertSame(info2, getThrottler().mLastPendingInfo);
+        clearInvocations(getThrottler());
+
+        // When the delayed task fires, the queued notification info will be used to update
+        // notification.
+        advanceTimeByMillis(THROTTLE_MILLIS);
+        verify(getThrottler()).showNotificationImmediately(info2);
+        assertNotNull(getThrottler().mTask);
+        assertNull(getThrottler().mLastPendingInfo);
+    }
+
+    @Test
+    public void testQueueingNotificationWontResetTimer() {
+        mMediaNotificationInfoBuilder.setPaused(false);
+        MediaNotificationInfo info1 = mMediaNotificationInfoBuilder.build();
+        mMediaNotificationInfoBuilder.setPaused(true);
+        MediaNotificationInfo info2 = mMediaNotificationInfoBuilder.build();
+
+        getThrottler().queueNotification(info1);
+        // Wait till the timer goes half way.
+        advanceTimeByMillis(THROTTLE_MILLIS / 2);
+        getThrottler().queueNotification(info2);
+
+        clearInvocations(getThrottler());
+
+        // The task should fire after |THROTTLE_MILLIS| since the it is posted.
+        advanceTimeByMillis(THROTTLE_MILLIS / 2);
+        verify(getThrottler()).showNotificationImmediately(info2);
+        assertNotNull(getThrottler().mTask);
+        assertNull(getThrottler().mLastPendingInfo);
+
+        // Can't check whether another task is posted due to the limitation of Robolectric shadows.
+    }
+
+    @Test
+    public void testQueueNotificationIgnoresNotification_Unthrottled() {
+        mMediaNotificationInfoBuilder.setPaused(false);
+        MediaNotificationInfo infoPlaying1 = mMediaNotificationInfoBuilder.build();
+        MediaNotificationInfo infoPlaying2 = mMediaNotificationInfoBuilder.build();
+        mMediaNotificationInfoBuilder.setPaused(true);
+        MediaNotificationInfo infoPaused1 = mMediaNotificationInfoBuilder.build();
+        MediaNotificationInfo infoPaused2 = mMediaNotificationInfoBuilder.build();
+
+        // This will update the notification immediately and enter throttled state.
+        getThrottler().queueNotification(infoPlaying1);
+
+        // This will not update the queued notification as it is the same as which stored in
+        // MediaNotificationManager.
+        getThrottler().queueNotification(infoPlaying2);
+        assertNull(getThrottler().mLastPendingInfo);
+
+        // This will update the queued notification info as it is a different one.
+        getThrottler().queueNotification(infoPaused1);
+        assertSame(infoPaused1, getThrottler().mLastPendingInfo);
+
+        // This will not update the queued notification info as it is the same with the queued info.
+        getThrottler().queueNotification(infoPaused2);
+        assertSame(infoPaused1, getThrottler().mLastPendingInfo);
+
+        // This will not update the queued notification info as it is different from the queued
+        // info.
+        getThrottler().queueNotification(infoPlaying1);
+        assertSame(infoPlaying1, getThrottler().mLastPendingInfo);
+    }
+
+    @Test
+    public void testQueueNotificationIgnoresNotification_Throttled() {
+        MediaNotificationInfo info1 = mMediaNotificationInfoBuilder.build();
+        MediaNotificationInfo info2 = mMediaNotificationInfoBuilder.build();
+
+        getThrottler().queueNotification(info1);
+        clearInvocations(getThrottler());
+        getThrottler().queueNotification(info2);
+
+        verify(getThrottler(), never())
+                .showNotificationImmediately(any(MediaNotificationInfo.class));
+        assertNotNull(getThrottler().mTask);
+        assertNull(getThrottler().mLastPendingInfo);
+    }
+
+    @Test
+    public void testClearNotificationClearsThrottler() {
+        MediaNotificationInfo info = mMediaNotificationInfoBuilder.build();
+        getThrottler().queueNotification(info);
+
+        getManager().clearNotification();
+
+        verify(getThrottler()).clearPendingNotifications();
+    }
+
+    @Test
+    public void testClearThrottler() {
+        MediaNotificationInfo info = mMediaNotificationInfoBuilder.build();
+        getThrottler().queueNotification(info);
+        getThrottler().clearPendingNotifications();
+        clearInvocations(getThrottler());
+
+        assertNull(getThrottler().mTask);
+        assertNull(getThrottler().mLastPendingInfo);
+
+        // Check the task is removed
+        advanceTimeByMillis(THROTTLE_MILLIS);
+
+        verify(getThrottler(), never())
+                .showNotificationImmediately(any(MediaNotificationInfo.class));
+    }
+
+    private MediaNotificationManager.Throttler getThrottler() {
+        return getManager().mThrottler;
+    }
+}