Make CacheDataSourceContractTest use FakeDataSource for upstream

It's more flexible to use FakeDataSource, since it allows to testing
different upstream behaviors (e.g., upstream not being able to resolve
the content length).

PiperOrigin-RevId: 362072899

library/core/src/test/java/com/google/android/exoplayer2/upstream/CacheDataSourceContractTest.java

@@ -20,6 +20,8 @@ import androidx.annotation.Nullable;
 import androidx.test.core.app.ApplicationProvider;
 import androidx.test.core.app.ApplicationProvider;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import com.google.android.exoplayer2.testutil.DataSourceContractTest;
 import com.google.android.exoplayer2.testutil.DataSourceContractTest;
+import com.google.android.exoplayer2.testutil.FakeDataSet;
+import com.google.android.exoplayer2.testutil.FakeDataSource;
 import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.upstream.cache.CacheDataSource;
 import com.google.android.exoplayer2.upstream.cache.CacheDataSource;
 import com.google.android.exoplayer2.upstream.cache.NoOpCacheEvictor;
 import com.google.android.exoplayer2.upstream.cache.NoOpCacheEvictor;
@@ -28,28 +30,36 @@ import com.google.android.exoplayer2.util.Util;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
 import java.io.File;
 import java.io.IOException;
 import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Paths;
 import org.junit.Before;
 import org.junit.Before;
-import org.junit.Rule;
-import org.junit.rules.TemporaryFolder;
 import org.junit.runner.RunWith;
 import org.junit.runner.RunWith;
 
 
 /** {@link DataSource} contract tests for {@link CacheDataSource}. */
 /** {@link DataSource} contract tests for {@link CacheDataSource}. */
 @RunWith(AndroidJUnit4.class)
 @RunWith(AndroidJUnit4.class)
 public class CacheDataSourceContractTest extends DataSourceContractTest {
 public class CacheDataSourceContractTest extends DataSourceContractTest {
-  private static final byte[] DATA = TestUtil.buildTestData(20);
-
-  @Rule public final TemporaryFolder tempFolder = new TemporaryFolder();
 
 
   private Uri simpleUri;
   private Uri simpleUri;
-  private FileDataSource fileDataSource;
+  private Uri unknownLengthUri;
+  private byte[] simpleData;
+  private byte[] unknownLengthData;
+  private FakeDataSet fakeDataSet;
+
+  private FakeDataSource upstreamDataSource;
 
 
   @Before
   @Before
   public void setUp() throws IOException {
   public void setUp() throws IOException {
-    File file = tempFolder.newFile();
-    Files.write(Paths.get(file.getAbsolutePath()), DATA);
-    simpleUri = Uri.fromFile(file);
+    simpleUri = Uri.parse("test://simple.test");
+    unknownLengthUri = Uri.parse("test://unknown-length.test");
+    simpleData = TestUtil.buildTestData(/* length= */ 20);
+    unknownLengthData = TestUtil.buildTestData(/* length= */ 40);
+    fakeDataSet =
+        new FakeDataSet()
+            .newData(simpleUri)
+            .appendReadData(simpleData)
+            .endData()
+            .newData(unknownLengthUri)
+            .setSimulateUnknownLength(true)
+            .appendReadData(unknownLengthData)
+            .endData();
   }
   }
 
 
   @Override
   @Override
@@ -58,13 +68,18 @@ public class CacheDataSourceContractTest extends DataSourceContractTest {
         new TestResource.Builder()
         new TestResource.Builder()
             .setName("simple")
             .setName("simple")
             .setUri(simpleUri)
             .setUri(simpleUri)
-            .setExpectedBytes(DATA)
+            .setExpectedBytes(simpleData)
+            .build(),
+        new TestResource.Builder()
+            .setName("unknown length")
+            .setUri(unknownLengthUri)
+            .setExpectedBytes(unknownLengthData)
             .build());
             .build());
   }
   }
 
 
   @Override
   @Override
   protected Uri getNotFoundUri() {
   protected Uri getNotFoundUri() {
-    return Uri.fromFile(tempFolder.getRoot().toPath().resolve("nonexistent").toFile());
+    return Uri.parse("test://not-found.test");
   }
   }
 
 
   @Override
   @Override
@@ -73,13 +88,13 @@ public class CacheDataSourceContractTest extends DataSourceContractTest {
         Util.createTempDirectory(ApplicationProvider.getApplicationContext(), "ExoPlayerTest");
         Util.createTempDirectory(ApplicationProvider.getApplicationContext(), "ExoPlayerTest");
     SimpleCache cache =
     SimpleCache cache =
         new SimpleCache(tempFolder, new NoOpCacheEvictor(), TestUtil.getInMemoryDatabaseProvider());
         new SimpleCache(tempFolder, new NoOpCacheEvictor(), TestUtil.getInMemoryDatabaseProvider());
-    fileDataSource = new FileDataSource();
-    return new CacheDataSource(cache, fileDataSource);
+    upstreamDataSource = new FakeDataSource(fakeDataSet);
+    return new CacheDataSource(cache, upstreamDataSource);
   }
   }
 
 
   @Override
   @Override
   @Nullable
   @Nullable
   protected DataSource getTransferListenerDataSource() {
   protected DataSource getTransferListenerDataSource() {
-    return fileDataSource;
+    return upstreamDataSource;
   }
   }
 }
 }