Make seek in FakeMediaPeriod more realistic.

Currently seeks are basically ignored. However, it's more realistic to re-queue the
single sample if the seek is to position 0.

PiperOrigin-RevId: 290273564

library/core/src/test/java/com/google/android/exoplayer2/analytics/AnalyticsCollectorTest.java

@@ -435,9 +435,8 @@ public final class AnalyticsCollectorTest {
     assertThat(listener.getEvents(EVENT_AUDIO_SESSION_ID)).containsExactly(period1Seq2);
     assertThat(listener.getEvents(EVENT_DROPPED_VIDEO_FRAMES))
         .containsExactly(period0, period1Seq2, period1Seq2);
-    assertThat(listener.getEvents(EVENT_VIDEO_SIZE_CHANGED)).containsExactly(period0, period1Seq2);
-    assertThat(listener.getEvents(EVENT_RENDERED_FIRST_FRAME))
-        .containsExactly(period0, period1Seq2);
+    assertThat(listener.getEvents(EVENT_VIDEO_SIZE_CHANGED)).containsExactly(period0, period0);
+    assertThat(listener.getEvents(EVENT_RENDERED_FIRST_FRAME)).containsExactly(period0, period0);
     listener.assertNoMoreEvents();
   }
 

testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeAdaptiveMediaPeriod.java

@@ -119,14 +119,6 @@ public class FakeAdaptiveMediaPeriod extends FakeMediaPeriod
     return sequenceableLoader.getBufferedPositionUs();
   }
 
-  @Override
-  public long seekToUs(long positionUs) {
-    for (ChunkSampleStream<FakeChunkSource> sampleStream : sampleStreams) {
-      sampleStream.seekToUs(positionUs);
-    }
-    return super.seekToUs(positionUs);
-  }
-
   @Override
   public long getNextLoadPositionUs() {
     super.getNextLoadPositionUs();
@@ -145,7 +137,8 @@ public class FakeAdaptiveMediaPeriod extends FakeMediaPeriod
   }
 
   @Override
-  protected SampleStream createSampleStream(TrackSelection trackSelection) {
+  protected SampleStream createSampleStream(
+      TrackSelection trackSelection, EventDispatcher eventDispatcher) {
     FakeChunkSource chunkSource =
         chunkSourceFactory.createChunkSource(trackSelection, durationUs, transferListener);
     return new ChunkSampleStream<>(
@@ -161,6 +154,12 @@ public class FakeAdaptiveMediaPeriod extends FakeMediaPeriod
         eventDispatcher);
   }
 
+  @Override
+  @SuppressWarnings("unchecked")
+  protected void seekSampleStream(SampleStream sampleStream, long positionUs) {
+    ((ChunkSampleStream<FakeChunkSource>) sampleStream).seekToUs(positionUs);
+  }
+
   @Override
   public void onContinueLoadingRequested(ChunkSampleStream<FakeChunkSource> source) {
     callback.onContinueLoadingRequested(this);

testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeMediaPeriod.java

@@ -28,11 +28,14 @@ import com.google.android.exoplayer2.source.MediaSourceEventListener.EventDispat
 import com.google.android.exoplayer2.source.SampleStream;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
+import com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem;
 import com.google.android.exoplayer2.trackselection.TrackSelection;
 import com.google.android.exoplayer2.upstream.DataSpec;
 import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Collections;
+import java.util.List;
 
 /**
  * Fake {@link MediaPeriod} that provides tracks from the given {@link TrackGroupArray}. Selecting
@@ -44,7 +47,8 @@ public class FakeMediaPeriod implements MediaPeriod {
   public static final DataSpec FAKE_DATA_SPEC = new DataSpec(Uri.parse("http://fake.uri"));
 
   private final TrackGroupArray trackGroupArray;
-  protected final EventDispatcher eventDispatcher;
+  private final List<SampleStream> sampleStreams;
+  private final EventDispatcher eventDispatcher;
 
   @Nullable private Handler playerHandler;
   @Nullable private Callback prepareCallback;
@@ -76,6 +80,7 @@ public class FakeMediaPeriod implements MediaPeriod {
     this.eventDispatcher = eventDispatcher;
     this.deferOnPrepared = deferOnPrepared;
     discontinuityPositionUs = C.TIME_UNSET;
+    sampleStreams = new ArrayList<>();
     eventDispatcher.mediaPeriodCreated();
   }
 
@@ -148,6 +153,7 @@ public class FakeMediaPeriod implements MediaPeriod {
   public long selectTracks(TrackSelection[] selections, boolean[] mayRetainStreamFlags,
       SampleStream[] streams, boolean[] streamResetFlags, long positionUs) {
     assertThat(prepared).isTrue();
+    sampleStreams.clear();
     int rendererCount = selections.length;
     for (int i = 0; i < rendererCount; i++) {
       if (streams[i] != null && (selections[i] == null || !mayRetainStreamFlags[i])) {
@@ -161,7 +167,8 @@ public class FakeMediaPeriod implements MediaPeriod {
         int indexInTrackGroup = selection.getIndexInTrackGroup(selection.getSelectedIndex());
         assertThat(indexInTrackGroup).isAtLeast(0);
         assertThat(indexInTrackGroup).isLessThan(trackGroup.length);
-        streams[i] = createSampleStream(selection);
+        streams[i] = createSampleStream(selection, eventDispatcher);
+        sampleStreams.add(streams[i]);
         streamResetFlags[i] = true;
       }
     }
@@ -199,12 +206,16 @@ public class FakeMediaPeriod implements MediaPeriod {
   @Override
   public long seekToUs(long positionUs) {
     assertThat(prepared).isTrue();
-    return positionUs + seekOffsetUs;
+    long seekPositionUs = positionUs + seekOffsetUs;
+    for (SampleStream sampleStream : sampleStreams) {
+      seekSampleStream(sampleStream, seekPositionUs);
+    }
+    return seekPositionUs;
   }
 
   @Override
   public long getAdjustedSeekPositionUs(long positionUs, SeekParameters seekParameters) {
-    return positionUs;
+    return positionUs + seekOffsetUs;
   }
 
   @Override
@@ -223,11 +234,35 @@ public class FakeMediaPeriod implements MediaPeriod {
     return false;
   }
 
-  protected SampleStream createSampleStream(TrackSelection selection) {
+  /**
+   * Creates a sample stream for the provided selection.
+   *
+   * @param selection A selection of tracks.
+   * @param eventDispatcher A dispatcher for events that should be used by the sample stream.
+   * @return A {@link SampleStream} for this selection.
+   */
+  protected SampleStream createSampleStream(
+      TrackSelection selection, EventDispatcher eventDispatcher) {
     return new FakeSampleStream(
         selection.getSelectedFormat(), eventDispatcher, /* shouldOutputSample= */ true);
   }
 
+  /**
+   * Seeks inside the given sample stream.
+   *
+   * @param sampleStream A sample stream that was created by a call to {@link
+   *     #createSampleStream(TrackSelection, EventDispatcher)}.
+   * @param positionUs The position to seek to, in microseconds.
+   */
+  protected void seekSampleStream(SampleStream sampleStream, long positionUs) {
+    if (positionUs == 0) {
+      // When seeking back to 0, queue our single sample at time 0 again.
+      ((FakeSampleStream) sampleStream)
+          .resetSampleStreamItems(
+              Collections.singletonList(new FakeSampleStreamItem(new byte[] {0})), /* timeUs= */ 0);
+    }
+  }
+
   private void finishPreparation() {
     prepared = true;
     prepareCallback.onPrepared(this);

testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeSampleStream.java

@@ -24,7 +24,6 @@ import com.google.android.exoplayer2.source.MediaSourceEventListener.EventDispat
 import com.google.android.exoplayer2.source.SampleStream;
 import java.io.IOException;
 import java.util.ArrayDeque;
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 
@@ -96,7 +95,7 @@ public final class FakeSampleStream implements SampleStream {
         format,
         eventDispatcher,
         shouldOutputSample
-            ? Arrays.asList(new FakeSampleStreamItem(new byte[] {0}))
+            ? Collections.singletonList(new FakeSampleStreamItem(new byte[] {0}))
             : Collections.emptyList(),
         /* timeUsIncrement= */ 0);
   }
@@ -122,6 +121,18 @@ public final class FakeSampleStream implements SampleStream {
     this.timeUsIncrement = timeUsIncrement;
   }
 
+  /**
+   * Resets the samples provided by this sample stream to the provided list.
+   *
+   * @param fakeSampleStreamItems The list of {@link FakeSampleStreamItem items} to provide.
+   * @param timeUs The time at which samples will start being output, in microseconds.
+   */
+  public void resetSampleStreamItems(List<FakeSampleStreamItem> fakeSampleStreamItems, int timeUs) {
+    this.fakeSampleStreamItems.clear();
+    this.fakeSampleStreamItems.addAll(fakeSampleStreamItems);
+    this.timeUs = timeUs;
+  }
+
   @Override
   public boolean isReady() {
     return true;