Improve housekeeping of ConcatenatingMediaSource callbacks.

When calling releaseSource(), all pending messages will be removed. That means
that all action-on-completion callbacks which are somewhere in flight are
just dropped without being called. This change adds code to keep track of the
current state of each callback to allow all of them being called when the
source is released.

Issue:#5464
PiperOrigin-RevId: 232312528

RELEASENOTES.md

@@ -58,6 +58,8 @@
 * OkHttp extension: Upgrade OkHttp dependency to 3.12.1.
 * MP3: Wider fix for issue where streams would play twice on some Samsung
   devices ([#4519](https://github.com/google/ExoPlayer/issues/4519)).
+* Fix issue with dropped messages when releasing a `ConcatenatingMediaSource`
+  ([#5464](https://github.com/google/ExoPlayer/issues/5464)).
 
 ### 2.9.4 ###
 

library/core/src/test/java/com/google/android/exoplayer2/source/ConcatenatingMediaSourceTest.java

@@ -17,6 +17,7 @@ package com.google.android.exoplayer2.source;
 
 import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.fail;
+import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
 
 import android.os.ConditionVariable;
@@ -25,6 +26,7 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Player;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.source.MediaSource.MediaPeriodId;
+import com.google.android.exoplayer2.source.MediaSource.SourceInfoRefreshListener;
 import com.google.android.exoplayer2.source.ShuffleOrder.DefaultShuffleOrder;
 import com.google.android.exoplayer2.testutil.DummyMainThread;
 import com.google.android.exoplayer2.testutil.FakeMediaSource;
@@ -42,7 +44,6 @@ import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.mockito.Mockito;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.annotation.Config;
 
@@ -416,7 +417,7 @@ public final class ConcatenatingMediaSourceTest {
 
   @Test
   public void testCustomCallbackBeforePreparationAddSingle() {
-    Runnable runnable = Mockito.mock(Runnable.class);
+    Runnable runnable = mock(Runnable.class);
 
     mediaSource.addMediaSource(createFakeMediaSource(), new Handler(), runnable);
     verify(runnable).run();
@@ -424,7 +425,7 @@ public final class ConcatenatingMediaSourceTest {
 
   @Test
   public void testCustomCallbackBeforePreparationAddMultiple() {
-    Runnable runnable = Mockito.mock(Runnable.class);
+    Runnable runnable = mock(Runnable.class);
 
     mediaSource.addMediaSources(
         Arrays.asList(new MediaSource[] {createFakeMediaSource(), createFakeMediaSource()}),
@@ -435,7 +436,7 @@ public final class ConcatenatingMediaSourceTest {
 
   @Test
   public void testCustomCallbackBeforePreparationAddSingleWithIndex() {
-    Runnable runnable = Mockito.mock(Runnable.class);
+    Runnable runnable = mock(Runnable.class);
 
     mediaSource.addMediaSource(/* index */ 0, createFakeMediaSource(), new Handler(), runnable);
     verify(runnable).run();
@@ -443,7 +444,7 @@ public final class ConcatenatingMediaSourceTest {
 
   @Test
   public void testCustomCallbackBeforePreparationAddMultipleWithIndex() {
-    Runnable runnable = Mockito.mock(Runnable.class);
+    Runnable runnable = mock(Runnable.class);
 
     mediaSource.addMediaSources(
         /* index */ 0,
@@ -455,7 +456,7 @@ public final class ConcatenatingMediaSourceTest {
 
   @Test
   public void testCustomCallbackBeforePreparationRemove() {
-    Runnable runnable = Mockito.mock(Runnable.class);
+    Runnable runnable = mock(Runnable.class);
 
     mediaSource.addMediaSource(createFakeMediaSource());
     mediaSource.removeMediaSource(/* index */ 0, new Handler(), runnable);
@@ -464,7 +465,7 @@ public final class ConcatenatingMediaSourceTest {
 
   @Test
   public void testCustomCallbackBeforePreparationMove() {
-    Runnable runnable = Mockito.mock(Runnable.class);
+    Runnable runnable = mock(Runnable.class);
 
     mediaSource.addMediaSources(
         Arrays.asList(new MediaSource[] {createFakeMediaSource(), createFakeMediaSource()}));
@@ -589,6 +590,29 @@ public final class ConcatenatingMediaSourceTest {
   }
 
   @Test
+  public void testCustomCallbackIsCalledAfterRelease() throws IOException {
+    DummyMainThread dummyMainThread = new DummyMainThread();
+    ConditionVariable callbackCalledCondition = new ConditionVariable();
+    try {
+      dummyMainThread.runOnMainThread(
+          () -> {
+            SourceInfoRefreshListener listener = mock(SourceInfoRefreshListener.class);
+            mediaSource.addMediaSources(Arrays.asList(createMediaSources(2)));
+            mediaSource.prepareSource(listener, /* mediaTransferListener= */ null);
+            mediaSource.moveMediaSource(
+                /* currentIndex= */ 0,
+                /* newIndex= */ 1,
+                new Handler(),
+                callbackCalledCondition::open);
+            mediaSource.releaseSource(listener);
+          });
+      assertThat(callbackCalledCondition.block(MediaSourceTestRunner.TIMEOUT_MS)).isTrue();
+    } finally {
+      dummyMainThread.release();
+    }
+  }
+
+  @Test
   public void testPeriodCreationWithAds() throws IOException, InterruptedException {
     // Create concatenated media source with ad child source.
     Timeline timelineContentOnly =
@@ -973,7 +997,7 @@ public final class ConcatenatingMediaSourceTest {
 
   @Test
   public void testCustomCallbackBeforePreparationSetShuffleOrder() throws Exception {
-    Runnable runnable = Mockito.mock(Runnable.class);
+    Runnable runnable = mock(Runnable.class);
     mediaSource.setShuffleOrder(
         new ShuffleOrder.UnshuffledShuffleOrder(/* length= */ 0), new Handler(), runnable);