Run DownloadManager on a custom thread while testing

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185674707

library/core/src/androidTest/java/com/google/android/exoplayer2/offline/DownloadManagerTest.java

@@ -24,6 +24,7 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.offline.DownloadManager.DownloadListener;
 import com.google.android.exoplayer2.offline.DownloadManager.DownloadState;
 import com.google.android.exoplayer2.offline.DownloadManager.DownloadState.State;
+import com.google.android.exoplayer2.testutil.DummyMainThread;
 import com.google.android.exoplayer2.testutil.MockitoUtil;
 import com.google.android.exoplayer2.upstream.DummyDataSource;
 import com.google.android.exoplayer2.upstream.cache.Cache;
@@ -53,12 +54,13 @@ public class DownloadManagerTest extends InstrumentationTestCase {
   private DownloadManager downloadManager;
   private File actionFile;
   private TestDownloadListener testDownloadListener;
+  private DummyMainThread dummyMainThread;
 
   @Override
   public void setUp() throws Exception {
     super.setUp();
     MockitoUtil.setUpMockito(this);
-
+    dummyMainThread = new DummyMainThread();
     actionFile = Util.createTempFile(getInstrumentation().getContext(), "ExoPlayerTest");
     testDownloadListener = new TestDownloadListener();
     setUpDownloadManager(100);
@@ -68,6 +70,7 @@ public class DownloadManagerTest extends InstrumentationTestCase {
   public void tearDown() throws Exception {
     releaseDownloadManager();
     actionFile.delete();
+    dummyMainThread.release();
     super.tearDown();
   }
 
@@ -76,7 +79,7 @@ public class DownloadManagerTest extends InstrumentationTestCase {
       releaseDownloadManager();
     }
     try {
-      runTestOnUiThread(
+      runOnMainThread(
           new Runnable() {
             @Override
             public void run() {
@@ -98,7 +101,7 @@ public class DownloadManagerTest extends InstrumentationTestCase {
 
   private void releaseDownloadManager() throws Exception {
     try {
-      runTestOnUiThread(
+      runOnMainThread(
           new Runnable() {
             @Override
             public void run() {
@@ -345,7 +348,7 @@ public class DownloadManagerTest extends InstrumentationTestCase {
     remove2Action.post().assertStarted();
     download2Action.post().assertDoesNotStart();
 
-    runTestOnUiThread(
+    runOnMainThread(
         new Runnable() {
           @Override
           public void run() {
@@ -368,7 +371,7 @@ public class DownloadManagerTest extends InstrumentationTestCase {
     // New download actions can be added but they don't start.
     download3Action.post().assertDoesNotStart();
 
-    runTestOnUiThread(
+    runOnMainThread(
         new Runnable() {
           @Override
           public void run() {
@@ -393,7 +396,7 @@ public class DownloadManagerTest extends InstrumentationTestCase {
     // download3Action doesn't start as DM was configured to run two downloads in parallel.
     download3Action.post().assertDoesNotStart();
 
-    runTestOnUiThread(
+    runOnMainThread(
         new Runnable() {
           @Override
           public void run() {
@@ -404,7 +407,7 @@ public class DownloadManagerTest extends InstrumentationTestCase {
     // download1Action doesn't stop yet as it ignores interrupts.
     download2Action.assertStopped();
 
-    runTestOnUiThread(
+    runOnMainThread(
         new Runnable() {
           @Override
           public void run() {
@@ -462,6 +465,10 @@ public class DownloadManagerTest extends InstrumentationTestCase {
     return new FakeDownloadAction(mediaId, true);
   }
 
+  private void runOnMainThread(final Runnable r) throws Throwable {
+    dummyMainThread.runOnMainThread(r);
+  }
+
   private static final class TestDownloadListener implements DownloadListener {
 
     private ConditionVariable downloadFinishedCondition;
@@ -544,7 +551,7 @@ public class DownloadManagerTest extends InstrumentationTestCase {
     }
 
     private FakeDownloadAction post() throws Throwable {
-      runTestOnUiThread(
+      runOnMainThread(
           new Runnable() {
             @Override
             public void run() {

library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadManager.java

@@ -115,7 +115,12 @@ public final class DownloadManager {
 
     tasks = new ArrayList<>();
     activeDownloadTasks = new ArrayList<>();
-    handler = new Handler(Looper.getMainLooper());
+
+    Looper looper = Looper.myLooper();
+    if (looper == null) {
+      looper = Looper.getMainLooper();
+    }
+    handler = new Handler(looper);
 
     fileIOThread = new HandlerThread("DownloadManager file i/o");
     fileIOThread.start();

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

@@ -20,13 +20,12 @@ import static org.junit.Assert.fail;
 import static org.mockito.Mockito.verify;
 
 import android.os.ConditionVariable;
-import android.os.Handler;
-import android.os.HandlerThread;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Player;
 import com.google.android.exoplayer2.RobolectricUtil;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.source.MediaSource.MediaPeriodId;
+import com.google.android.exoplayer2.testutil.DummyMainThread;
 import com.google.android.exoplayer2.testutil.FakeMediaSource;
 import com.google.android.exoplayer2.testutil.FakeShuffleOrder;
 import com.google.android.exoplayer2.testutil.FakeTimeline;
@@ -779,40 +778,6 @@ public final class DynamicConcatenatingMediaSourceTest {
     return new FakeTimeline(new TimelineWindowDefinition(index + 1, (index + 1) * 111));
   }
 
-  private static final class DummyMainThread {
-
-    private final HandlerThread thread;
-    private final Handler handler;
-
-    private DummyMainThread() {
-      thread = new HandlerThread("DummyMainThread");
-      thread.start();
-      handler = new Handler(thread.getLooper());
-    }
-
-    /**
-     * Runs the provided {@link Runnable} on the main thread, blocking until execution completes.
-     *
-     * @param runnable The {@link Runnable} to run.
-     */
-    public void runOnMainThread(final Runnable runnable) {
-      final ConditionVariable finishedCondition = new ConditionVariable();
-      handler.post(
-          new Runnable() {
-            @Override
-            public void run() {
-              runnable.run();
-              finishedCondition.open();
-            }
-          });
-      assertThat(finishedCondition.block(MediaSourceTestRunner.TIMEOUT_MS)).isTrue();
-    }
-
-    public void release() {
-      thread.quit();
-    }
-  }
-
   private static final class TimelineGrabber implements Runnable {
 
     private final MediaSourceTestRunner testRunner;

library/dash/src/androidTest/java/com/google/android/exoplayer2/source/dash/offline/DownloadManagerDashTest.java

@@ -28,6 +28,7 @@ import android.test.UiThreadTest;
 import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
+import com.google.android.exoplayer2.testutil.DummyMainThread;
 import com.google.android.exoplayer2.testutil.FakeDataSet;
 import com.google.android.exoplayer2.testutil.FakeDataSource;
 import com.google.android.exoplayer2.testutil.MockitoUtil;
@@ -53,11 +54,13 @@ public class DownloadManagerDashTest extends InstrumentationTestCase {
   private RepresentationKey fakeRepresentationKey2;
   private TestDownloadListener downloadListener;
   private File actionFile;
+  private DummyMainThread dummyMainThread;
 
   @UiThreadTest
   @Override
   public void setUp() throws Exception {
     super.setUp();
+    dummyMainThread = new DummyMainThread();
     Context context = getInstrumentation().getContext();
     tempFolder = Util.createTempDirectory(context, "ExoPlayerTest");
     File cacheFolder = new File(tempFolder, "cache");
@@ -85,6 +88,7 @@ public class DownloadManagerDashTest extends InstrumentationTestCase {
   public void tearDown() throws Exception {
     downloadManager.release();
     Util.recursiveDelete(tempFolder);
+    dummyMainThread.release();
     super.tearDown();
   }
 
@@ -111,7 +115,7 @@ public class DownloadManagerDashTest extends InstrumentationTestCase {
 
     // Run DM accessing code on UI/main thread as it should be. Also not to block handling of loaded
     // actions.
-    runTestOnUiThread(
+    dummyMainThread.runOnMainThread(
         new Runnable() {
           @Override
           public void run() {
@@ -226,18 +230,25 @@ public class DownloadManagerDashTest extends InstrumentationTestCase {
   }
 
   private void createDownloadManager() {
-    Factory fakeDataSourceFactory = new FakeDataSource.Factory(null).setFakeDataSet(fakeDataSet);
-    downloadManager =
-        new DownloadManager(
-            new DownloaderConstructorHelper(cache, fakeDataSourceFactory),
-            1,
-            3,
-            actionFile.getAbsolutePath(),
-            DashDownloadAction.DESERIALIZER);
-
-    downloadListener = new TestDownloadListener(downloadManager, this);
-    downloadManager.addListener(downloadListener);
-    downloadManager.startDownloads();
+    dummyMainThread.runOnMainThread(
+        new Runnable() {
+          @Override
+          public void run() {
+            Factory fakeDataSourceFactory =
+                new FakeDataSource.Factory(null).setFakeDataSet(fakeDataSet);
+            downloadManager =
+                new DownloadManager(
+                    new DownloaderConstructorHelper(cache, fakeDataSourceFactory),
+                    1,
+                    3,
+                    actionFile.getAbsolutePath(),
+                    DashDownloadAction.DESERIALIZER);
+
+            downloadListener = new TestDownloadListener(downloadManager, dummyMainThread);
+            downloadManager.addListener(downloadListener);
+            downloadManager.startDownloads();
+          }
+        });
   }
 
 }

library/dash/src/androidTest/java/com/google/android/exoplayer2/source/dash/offline/DownloadServiceDashTest.java

@@ -27,6 +27,7 @@ import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloadService;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
+import com.google.android.exoplayer2.testutil.DummyMainThread;
 import com.google.android.exoplayer2.testutil.FakeDataSet;
 import com.google.android.exoplayer2.testutil.FakeDataSource;
 import com.google.android.exoplayer2.testutil.TestUtil;
@@ -38,6 +39,7 @@ import com.google.android.exoplayer2.util.Util;
 import com.google.android.exoplayer2.util.scheduler.Requirements;
 import com.google.android.exoplayer2.util.scheduler.Scheduler;
 import java.io.File;
+import java.io.IOException;
 
 /**
  * Unit tests for {@link DownloadService}.
@@ -53,10 +55,12 @@ public class DownloadServiceDashTest extends InstrumentationTestCase {
   private DownloadService dashDownloadService;
   private ConditionVariable pauseDownloadCondition;
   private TestDownloadListener testDownloadListener;
+  private DummyMainThread dummyMainThread;
 
   @Override
   public void setUp() throws Exception {
     super.setUp();
+    dummyMainThread = new DummyMainThread();
     tempFolder = Util.createTempDirectory(getInstrumentation().getContext(), "ExoPlayerTest");
     cache = new SimpleCache(tempFolder, new NoOpCacheEvictor());
 
@@ -84,31 +88,36 @@ public class DownloadServiceDashTest extends InstrumentationTestCase {
         .setRandomData("text_segment_1", 1)
         .setRandomData("text_segment_2", 2)
         .setRandomData("text_segment_3", 3);
-    DataSource.Factory fakeDataSourceFactory = new FakeDataSource.Factory(null)
-        .setFakeDataSet(fakeDataSet);
+    final DataSource.Factory fakeDataSourceFactory =
+        new FakeDataSource.Factory(null).setFakeDataSet(fakeDataSet);
     fakeRepresentationKey1 = new RepresentationKey(0, 0, 0);
     fakeRepresentationKey2 = new RepresentationKey(0, 1, 0);
 
     context = getInstrumentation().getContext();
 
-    File actionFile = Util.createTempFile(context, "ExoPlayerTest");
-    actionFile.delete();
-    final DownloadManager dashDownloadManager =
-        new DownloadManager(
-            new DownloaderConstructorHelper(cache, fakeDataSourceFactory),
-            1,
-            3,
-            actionFile.getAbsolutePath(),
-            DashDownloadAction.DESERIALIZER);
-    testDownloadListener = new TestDownloadListener(dashDownloadManager, this);
-    dashDownloadManager.addListener(testDownloadListener);
-    dashDownloadManager.startDownloads();
-
     try {
-      runTestOnUiThread(
+      dummyMainThread.runOnMainThread(
           new Runnable() {
             @Override
             public void run() {
+              File actionFile = null;
+              try {
+                actionFile = Util.createTempFile(context, "ExoPlayerTest");
+              } catch (IOException e) {
+                throw new RuntimeException(e);
+              }
+              actionFile.delete();
+              final DownloadManager dashDownloadManager =
+                  new DownloadManager(
+                      new DownloaderConstructorHelper(cache, fakeDataSourceFactory),
+                      1,
+                      3,
+                      actionFile.getAbsolutePath(),
+                      DashDownloadAction.DESERIALIZER);
+              testDownloadListener = new TestDownloadListener(dashDownloadManager, dummyMainThread);
+              dashDownloadManager.addListener(testDownloadListener);
+              dashDownloadManager.startDownloads();
+
               dashDownloadService =
                   new DownloadService(101010) {
 
@@ -143,16 +152,18 @@ public class DownloadServiceDashTest extends InstrumentationTestCase {
   @Override
   public void tearDown() throws Exception {
     try {
-      runTestOnUiThread(new Runnable() {
-          @Override
-          public void run() {
-            dashDownloadService.onDestroy();
-          }
-        });
+      dummyMainThread.runOnMainThread(
+          new Runnable() {
+            @Override
+            public void run() {
+              dashDownloadService.onDestroy();
+            }
+          });
     } catch (Throwable throwable) {
       throw new Exception(throwable);
     }
     Util.recursiveDelete(tempFolder);
+    dummyMainThread.release();
     super.tearDown();
   }
 
@@ -197,7 +208,7 @@ public class DownloadServiceDashTest extends InstrumentationTestCase {
   }
 
   private void callDownloadServiceOnStart(final DashDownloadAction action) throws Throwable {
-    runTestOnUiThread(
+    dummyMainThread.runOnMainThread(
         new Runnable() {
           @Override
           public void run() {

library/dash/src/androidTest/java/com/google/android/exoplayer2/source/dash/offline/TestDownloadListener.java

@@ -17,10 +17,10 @@ package com.google.android.exoplayer2.source.dash.offline;
 
 import static com.google.common.truth.Truth.assertThat;
 
-import android.test.InstrumentationTestCase;
 import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloadManager.DownloadListener;
 import com.google.android.exoplayer2.offline.DownloadManager.DownloadState;
+import com.google.android.exoplayer2.testutil.DummyMainThread;
 
 /** A {@link DownloadListener} for testing. */
 /*package*/ final class TestDownloadListener implements DownloadListener {
@@ -28,13 +28,13 @@ import com.google.android.exoplayer2.offline.DownloadManager.DownloadState;
   private static final int TIMEOUT = 1000;
 
   private final DownloadManager downloadManager;
-  private final InstrumentationTestCase testCase;
+  private final DummyMainThread dummyMainThread;
   private final android.os.ConditionVariable downloadFinishedCondition;
   private Throwable downloadError;
 
-  public TestDownloadListener(DownloadManager downloadManager, InstrumentationTestCase testCase) {
+  public TestDownloadListener(DownloadManager downloadManager, DummyMainThread dummyMainThread) {
     this.downloadManager = downloadManager;
-    this.testCase = testCase;
+    this.dummyMainThread = dummyMainThread;
     this.downloadFinishedCondition = new android.os.ConditionVariable();
   }
 
@@ -55,7 +55,7 @@ import com.google.android.exoplayer2.offline.DownloadManager.DownloadState;
    * error.
    */
   public void blockUntilTasksCompleteAndThrowAnyDownloadError() throws Throwable {
-    testCase.runTestOnUiThread(
+    dummyMainThread.runOnMainThread(
         new Runnable() {
           @Override
           public void run() {

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

+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.exoplayer2.testutil;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.os.ConditionVariable;
+import android.os.Handler;
+import android.os.HandlerThread;
+
+/** Helper class to simulate main/UI thread in tests. */
+public final class DummyMainThread {
+
+  /** Default timeout value used for {@link #runOnMainThread(Runnable)}. */
+  public static final int TIMEOUT_MS = 10000;
+
+  private final HandlerThread thread;
+  private final Handler handler;
+
+  public DummyMainThread() {
+    thread = new HandlerThread("DummyMainThread");
+    thread.start();
+    handler = new Handler(thread.getLooper());
+  }
+
+  /**
+   * Runs the provided {@link Runnable} on the main thread, blocking until execution completes or
+   * until {@link #TIMEOUT_MS} milliseconds have passed.
+   *
+   * @param runnable The {@link Runnable} to run.
+   */
+  public void runOnMainThread(final Runnable runnable) {
+    runOnMainThread(TIMEOUT_MS, runnable);
+  }
+
+  /**
+   * Runs the provided {@link Runnable} on the main thread, blocking until execution completes or
+   * until timeout milliseconds have passed.
+   *
+   * @param timeoutMs the maximum time to wait in milliseconds.
+   * @param runnable The {@link Runnable} to run.
+   */
+  public void runOnMainThread(int timeoutMs, final Runnable runnable) {
+    final ConditionVariable finishedCondition = new ConditionVariable();
+    handler.post(
+        new Runnable() {
+          @Override
+          public void run() {
+            runnable.run();
+            finishedCondition.open();
+          }
+        });
+    assertThat(finishedCondition.block(timeoutMs)).isTrue();
+  }
+
+  public void release() {
+    thread.quit();
+  }
+}