Merge ContentDataSource fixes + tests from GitHub

https://github.com/google/ExoPlayer/pull/2963/files
8bb643976f

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=160128047

library/core/src/androidTest/java/com/google/android/exoplayer2/upstream/AssetDataSourceTest.java

@@ -15,10 +15,8 @@
  */
 package com.google.android.exoplayer2.upstream;
 
-import android.content.Context;
 import android.net.Uri;
 import android.test.InstrumentationTestCase;
-import android.test.MoreAsserts;
 import com.google.android.exoplayer2.testutil.TestUtil;
 
 /**
@@ -27,36 +25,19 @@ import com.google.android.exoplayer2.testutil.TestUtil;
 public final class AssetDataSourceTest extends InstrumentationTestCase {
 
   private static final String DATA_PATH = "binary/1024_incrementing_bytes.mp3";
-  private static final long DATA_LENGTH = 1024;
 
   public void testReadFileUri() throws Exception {
-    Context context = getInstrumentation().getContext();
+    AssetDataSource dataSource = new AssetDataSource(getInstrumentation().getContext());
-    AssetDataSource dataSource = new AssetDataSource(context);
+    DataSpec dataSpec = new DataSpec(Uri.parse("file:///android_asset/" + DATA_PATH));
-    Uri assetUri = Uri.parse("file:///android_asset/" + DATA_PATH);
+    TestUtil.assertDataSourceContent(dataSource, dataSpec,
-    DataSpec dataSpec = new DataSpec(assetUri);
+        TestUtil.getByteArray(getInstrumentation(), DATA_PATH));
-    try {
-      long length = dataSource.open(dataSpec);
-      assertEquals(DATA_LENGTH, length);
-      byte[] readData = TestUtil.readToEnd(dataSource);
-      MoreAsserts.assertEquals(TestUtil.getByteArray(getInstrumentation(), DATA_PATH), readData);
-    } finally {
-      dataSource.close();
-    }
   }
 
   public void testReadAssetUri() throws Exception {
-    Context context = getInstrumentation().getContext();
+    AssetDataSource dataSource = new AssetDataSource(getInstrumentation().getContext());
-    AssetDataSource dataSource = new AssetDataSource(context);
+    DataSpec dataSpec = new DataSpec(Uri.parse("asset:///" + DATA_PATH));
-    Uri assetUri = Uri.parse("asset:///" + DATA_PATH);
+    TestUtil.assertDataSourceContent(dataSource, dataSpec,
-    DataSpec dataSpec = new DataSpec(assetUri);
+        TestUtil.getByteArray(getInstrumentation(), DATA_PATH));
-    try {
-      long length = dataSource.open(dataSpec);
-      assertEquals(DATA_LENGTH, length);
-      byte[] readData = TestUtil.readToEnd(dataSource);
-      MoreAsserts.assertEquals(TestUtil.getByteArray(getInstrumentation(), DATA_PATH), readData);
-    } finally {
-      dataSource.close();
-    }
   }
 
 }

library/core/src/androidTest/java/com/google/android/exoplayer2/upstream/ContentDataSourceTest.java

@@ -23,7 +23,6 @@ import android.database.Cursor;
 import android.net.Uri;
 import android.support.annotation.NonNull;
 import android.test.InstrumentationTestCase;
-import android.test.MoreAsserts;
 import com.google.android.exoplayer2.testutil.TestUtil;
 import java.io.FileNotFoundException;
 import java.io.IOException;
@@ -35,7 +34,6 @@ public final class ContentDataSourceTest extends InstrumentationTestCase {
 
   private static final String AUTHORITY = "com.google.android.exoplayer2.core.test";
   private static final String DATA_PATH = "binary/1024_incrementing_bytes.mp3";
-  private static final long DATA_LENGTH = 1024;
 
   public void testReadValidUri() throws Exception {
     ContentDataSource dataSource = new ContentDataSource(getInstrumentation().getContext());
@@ -44,14 +42,8 @@ public final class ContentDataSourceTest extends InstrumentationTestCase {
         .authority(AUTHORITY)
         .path(DATA_PATH).build();
     DataSpec dataSpec = new DataSpec(contentUri);
-    try {
+    TestUtil.assertDataSourceContent(dataSource, dataSpec,
-      long length = dataSource.open(dataSpec);
+        TestUtil.getByteArray(getInstrumentation(), DATA_PATH));
-      assertEquals(DATA_LENGTH, length);
-      byte[] readData = TestUtil.readToEnd(dataSource);
-      MoreAsserts.assertEquals(TestUtil.getByteArray(getInstrumentation(), DATA_PATH), readData);
-    } finally {
-      dataSource.close();
-    }
   }
 
   public void testReadInvalidUri() throws Exception {
@@ -66,6 +58,7 @@ public final class ContentDataSourceTest extends InstrumentationTestCase {
       fail();
     } catch (ContentDataSource.ContentDataSourceException e) {
       // Expected.
+      assertTrue(e.getCause() instanceof FileNotFoundException);
     } finally {
       dataSource.close();
     }

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

@@ -17,12 +17,14 @@ package com.google.android.exoplayer2.testutil;
 
 import android.app.Instrumentation;
 import android.test.InstrumentationTestCase;
+import android.test.MoreAsserts;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.extractor.Extractor;
 import com.google.android.exoplayer2.extractor.PositionHolder;
 import com.google.android.exoplayer2.extractor.SeekMap;
 import com.google.android.exoplayer2.testutil.FakeExtractorInput.SimulatedIOException;
 import com.google.android.exoplayer2.upstream.DataSource;
+import com.google.android.exoplayer2.upstream.DataSpec;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
@@ -390,4 +392,24 @@ public class TestUtil {
     }
   }
 
+  /**
+   * Asserts that data read from a {@link DataSource} matches {@code expected}.
+   *
+   * @param dataSource The {@link DataSource} through which to read.
+   * @param dataSpec The {@link DataSpec} to use when opening the {@link DataSource}.
+   * @param expectedData The expected data.
+   * @throws IOException If an error occurs reading fom the {@link DataSource}.
+   */
+  public static void assertDataSourceContent(DataSource dataSource, DataSpec dataSpec,
+      byte[] expectedData) throws IOException {
+    try {
+      long length = dataSource.open(dataSpec);
+      Assert.assertEquals(length, expectedData.length);
+      byte[] readData = TestUtil.readToEnd(dataSource);
+      MoreAsserts.assertEquals(expectedData, readData);
+    } finally {
+      dataSource.close();
+    }
+  }
+
 }