From bd24ec08d13d74f2aae417b85f4cb40092c13f7e Mon Sep 17 00:00:00 2001
From: ivanbuper <ivanbuper@google.com>
Date: Thu, 1 May 2025 05:30:34 -0700
Subject: [PATCH] Add test to catch single asset audio sequence underruns

This test previews a composition containing only a single audio asset
sequence. The audio asset is a 1s, stereo, locally available WAV file.
Catching an underrun in this test is a likely indication of something
being seriously wrong with the device's state or a performance
regression on the audio pipeline.

This test is a verification of the fix in https://github.com/androidx/media/commit/2e20d35c3d5769e61516401cfddc8ea5d0de9de3. Without this fix
the newly added test fails because MediaCodecAudioRenderer attempts to
use dynamic scheduling with AudioGraphInputAudioSync
(which is unsupported) after EoS is signalled.

PiperOrigin-RevId: 753552825
---
 .../transformer/CompositionPlaybackTest.java  | 42 +++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/libraries/transformer/src/androidTest/java/androidx/media3/transformer/CompositionPlaybackTest.java b/libraries/transformer/src/androidTest/java/androidx/media3/transformer/CompositionPlaybackTest.java
index 1a35d3b235..ee87420d8a 100644
--- a/libraries/transformer/src/androidTest/java/androidx/media3/transformer/CompositionPlaybackTest.java
+++ b/libraries/transformer/src/androidTest/java/androidx/media3/transformer/CompositionPlaybackTest.java
@@ -35,11 +35,14 @@ import androidx.media3.common.PlaybackException;
 import androidx.media3.common.Player;
 import androidx.media3.common.util.NullableType;
 import androidx.media3.effect.GlEffect;
+import androidx.media3.exoplayer.audio.AudioSink;
+import androidx.media3.exoplayer.audio.DefaultAudioSink;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeoutException;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 import org.junit.After;
@@ -504,6 +507,45 @@ public class CompositionPlaybackTest {
         .isEqualTo(expectedTimestampsUs);
   }
 
+  @Test
+  public void playback_singleAssetAudioSequence_doesNotUnderrun()
+      throws PlaybackException, TimeoutException {
+    EditedMediaItem clip =
+        new EditedMediaItem.Builder(MediaItem.fromUri(AndroidTestUtil.WAV_ASSET.uri))
+            .setDurationUs(1_000_000L)
+            .build();
+    Composition composition =
+        new Composition.Builder(new EditedMediaItemSequence.Builder(clip).build()).build();
+    AtomicInteger underrunCount = new AtomicInteger();
+    AudioSink.Listener sinkListener =
+        new AudioSink.Listener() {
+          @Override
+          public void onPositionDiscontinuity() {}
+
+          @Override
+          public void onUnderrun(int bufferSize, long bufferSizeMs, long elapsedSinceLastFeedMs) {
+            underrunCount.addAndGet(1);
+          }
+
+          @Override
+          public void onSkipSilenceEnabledChanged(boolean skipSilenceEnabled) {}
+        };
+    AudioSink sink = new DefaultAudioSink.Builder(context).build();
+    sink.setListener(sinkListener);
+
+    getInstrumentation()
+        .runOnMainSync(
+            () -> {
+              player = new CompositionPlayer.Builder(context).setAudioSink(sink).build();
+              player.addListener(playerTestListener);
+              player.setComposition(composition);
+              player.prepare();
+              player.play();
+            });
+    playerTestListener.waitUntilPlayerEnded();
+    assertThat(underrunCount.get()).isEqualTo(0);
+  }
+
   private void runCompositionPlayer(Composition composition)
       throws PlaybackException, TimeoutException {
     runCompositionPlayer(composition, /* videoPrewarmingEnabled= */ true);