Add DefaultLoadControl test for starting playback

Also refactor the tests to make them behavioral (rather than testing the method)
and inline simple assertions.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=191867614

library/core/src/test/java/com/google/android/exoplayer2/DefaultLoadControlShouldContinueLoadingTest.java → library/core/src/test/java/com/google/android/exoplayer2/DefaultLoadControlTest.java

@@ -24,17 +24,18 @@ import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.robolectric.RobolectricTestRunner;
 
-/** Unit test for {@link DefaultLoadControl#shouldContinueLoading(long, float)}. */
+/** Unit tests for {@link DefaultLoadControl}. */
 @RunWith(RobolectricTestRunner.class)
-public class DefaultLoadControlShouldContinueLoadingTest {
+public class DefaultLoadControlTest {
 
-  private static final int PLAYBACK_SPEED = 1;
-  private static final int MIN_BUFFER_MS = DefaultLoadControl.DEFAULT_MIN_BUFFER_MS;
-  private static final int MAX_BUFFER_MS = DefaultLoadControl.DEFAULT_MAX_BUFFER_MS;
+  private static final float SPEED = 1f;
+  private static final long MIN_BUFFER_US = C.msToUs(DefaultLoadControl.DEFAULT_MIN_BUFFER_MS);
+  private static final long MAX_BUFFER_US = C.msToUs(DefaultLoadControl.DEFAULT_MAX_BUFFER_MS);
   private static final int TARGET_BUFFER_BYTES = C.DEFAULT_BUFFER_SEGMENT_SIZE * 2;
+
   private Builder builder;
   private DefaultAllocator allocator;
-  private DefaultLoadControl defaultLoadControl;
+  private DefaultLoadControl loadControl;
 
   @Before
   public void setUp() throws Exception {
@@ -43,54 +44,59 @@ public class DefaultLoadControlShouldContinueLoadingTest {
   }
 
   @Test
-  public void testReturnsTrueUntilMaximumBufferExceeded() throws Exception {
+  public void testShouldContinueLoading_untilMaxBufferExceeded() {
     createDefaultLoadControl();
-    assertThatShouldContinueLoadingReturnsTrue(0);
-    assertThatShouldContinueLoadingReturnsTrue(MIN_BUFFER_MS);
-    assertThatShouldContinueLoadingReturnsTrue(MAX_BUFFER_MS);
-    assertThatShouldContinueLoadingReturnsFalse(MAX_BUFFER_MS + 1);
+    assertThat(loadControl.shouldContinueLoading(/* bufferedDurationUs= */ 0, SPEED)).isTrue();
+    assertThat(loadControl.shouldContinueLoading(MIN_BUFFER_US, SPEED)).isTrue();
+    assertThat(loadControl.shouldContinueLoading(MAX_BUFFER_US, SPEED)).isTrue();
+    assertThat(loadControl.shouldContinueLoading(MAX_BUFFER_US + 1, SPEED)).isFalse();
   }
 
   @Test
-  public void testReturnsFalseUntilFallBelowMinimumBufferOnceBufferingStopped() throws Exception {
+  public void testShouldNotContinueLoadingOnceBufferingStopped_untilBelowMinBuffer() {
     createDefaultLoadControl();
-    assertThatShouldContinueLoadingReturnsFalse(MAX_BUFFER_MS + 1);
-    assertThatShouldContinueLoadingReturnsFalse(MAX_BUFFER_MS);
-    assertThatShouldContinueLoadingReturnsFalse(MIN_BUFFER_MS);
-    assertThatShouldContinueLoadingReturnsTrue(MIN_BUFFER_MS - 1);
+    assertThat(loadControl.shouldContinueLoading(MAX_BUFFER_US + 1, SPEED)).isFalse();
+    assertThat(loadControl.shouldContinueLoading(MAX_BUFFER_US, SPEED)).isFalse();
+    assertThat(loadControl.shouldContinueLoading(MIN_BUFFER_US, SPEED)).isFalse();
+    assertThat(loadControl.shouldContinueLoading(MIN_BUFFER_US - 1, SPEED)).isTrue();
   }
 
   @Test
-  public void testReturnsTrueUntilMinimumBufferReachedAlthoughTargetBufferBytesReached()
-      throws Exception {
+  public void testShouldContinueLoadingWithTargetBufferBytesReached_untilMinBufferReached() {
     createDefaultLoadControl();
     makeSureTargetBufferBytesReached();
 
-    assertThatShouldContinueLoadingReturnsTrue(0);
-    assertThatShouldContinueLoadingReturnsTrue(MIN_BUFFER_MS - 1);
-    assertThatShouldContinueLoadingReturnsFalse(MIN_BUFFER_MS);
-    assertThatShouldContinueLoadingReturnsFalse(MAX_BUFFER_MS + 1);
+    assertThat(loadControl.shouldContinueLoading(/* bufferedDurationUs= */ 0, SPEED)).isTrue();
+    assertThat(loadControl.shouldContinueLoading(MIN_BUFFER_US - 1, SPEED)).isTrue();
+    assertThat(loadControl.shouldContinueLoading(MIN_BUFFER_US, SPEED)).isFalse();
+    assertThat(loadControl.shouldContinueLoading(MAX_BUFFER_US + 1, SPEED)).isFalse();
   }
 
   @Test
-  public void testAlwaysReturnsFalseIfMaximumBufferReachedAndNotPrioritizeTimeOverSizeThresholds()
-      throws Exception {
+  public void testShouldNeverContinueLoading_ifMaxBufferReachedAndNotPrioritizeTimeOverSize() {
     builder.setPrioritizeTimeOverSizeThresholds(false);
     createDefaultLoadControl();
-    // Put defaultLoadControl in buffering state.
-    assertThatShouldContinueLoadingReturnsTrue(0);
+    // Put loadControl in buffering state.
+    assertThat(loadControl.shouldContinueLoading(/* bufferedDurationUs= */ 0, SPEED)).isTrue();
     makeSureTargetBufferBytesReached();
 
-    assertThatShouldContinueLoadingReturnsFalse(0);
-    assertThatShouldContinueLoadingReturnsFalse(MIN_BUFFER_MS);
-    assertThatShouldContinueLoadingReturnsFalse(MAX_BUFFER_MS + 1);
+    assertThat(loadControl.shouldContinueLoading(/* bufferedDurationUs= */ 0, SPEED)).isFalse();
+    assertThat(loadControl.shouldContinueLoading(MIN_BUFFER_US, SPEED)).isFalse();
+    assertThat(loadControl.shouldContinueLoading(MAX_BUFFER_US + 1, SPEED)).isFalse();
+  }
+
+  @Test
+  public void testStartsPlayback_whenMinBufferSizeReached() {
+    createDefaultLoadControl();
+    assertThat(loadControl.shouldStartPlayback(MIN_BUFFER_US, SPEED, /* rebuffering= */ false))
+        .isTrue();
   }
 
   private void createDefaultLoadControl() {
     builder.setAllocator(allocator);
     builder.setTargetBufferBytes(TARGET_BUFFER_BYTES);
-    defaultLoadControl = builder.createDefaultLoadControl();
-    defaultLoadControl.onTracksSelected(new Renderer[0], null, null);
+    loadControl = builder.createDefaultLoadControl();
+    loadControl.onTracksSelected(new Renderer[0], null, null);
   }
 
   private void makeSureTargetBufferBytesReached() {
@@ -99,13 +105,4 @@ public class DefaultLoadControlShouldContinueLoadingTest {
     }
   }
 
-  private void assertThatShouldContinueLoadingReturnsFalse(int bufferedDurationMs) {
-    assertThat(defaultLoadControl.shouldContinueLoading(bufferedDurationMs * 1000, PLAYBACK_SPEED))
-        .isFalse();
-  }
-
-  private void assertThatShouldContinueLoadingReturnsTrue(int bufferedDurationMs) {
-    assertThat(defaultLoadControl.shouldContinueLoading(bufferedDurationMs * 1000, PLAYBACK_SPEED))
-        .isTrue();
-  }
 }