Add `DataSource` contract test checking scheme case insensitivity

Systems accepting URIs should treat schemes as case-insensitive
([RFC 3986 Section 3.1](https://www.rfc-editor.org/rfc/rfc3986#section-3.1)):
>  An implementation should accept uppercase letters as equivalent to
>  lowercase in scheme names (e.g., allow "HTTP" as well as "http") for
>  the sake of robustness

PiperOrigin-RevId: 528735287

library/datasource/src/main/java/com/google/android/exoplayer2/upstream/ContentDataSource.java

@@ -73,13 +73,13 @@ public final class ContentDataSource extends BaseDataSource {
   @SuppressWarnings("InlinedApi") // We are inlining EXTRA_ACCEPT_ORIGINAL_MEDIA_FORMAT.
   public long open(DataSpec dataSpec) throws ContentDataSourceException {
     try {
-      Uri uri = dataSpec.uri;
+      Uri uri = dataSpec.uri.normalizeScheme();
       this.uri = uri;
 
       transferInitializing(dataSpec);
 
       AssetFileDescriptor assetFileDescriptor;
-      if ("content".equals(dataSpec.uri.getScheme())) {
+      if ("content".equals(uri.getScheme())) {
         Bundle providerOptions = new Bundle();
         // We don't want compatible media transcoding.
         providerOptions.putBoolean(MediaStore.EXTRA_ACCEPT_ORIGINAL_MEDIA_FORMAT, true);

library/datasource/src/main/java/com/google/android/exoplayer2/upstream/DataSchemeDataSource.java

@@ -48,7 +48,7 @@ public final class DataSchemeDataSource extends BaseDataSource {
   public long open(DataSpec dataSpec) throws IOException {
     transferInitializing(dataSpec);
     this.dataSpec = dataSpec;
-    Uri uri = dataSpec.uri;
+    Uri uri = dataSpec.uri.normalizeScheme();
     String scheme = uri.getScheme();
     Assertions.checkArgument(SCHEME_DATA.equals(scheme), "Unsupported scheme: " + scheme);
     String[] uriParts = Util.split(uri.getSchemeSpecificPart(), ",");

library/datasource/src/main/java/com/google/android/exoplayer2/upstream/RawResourceDataSource.java

@@ -114,7 +114,7 @@ public final class RawResourceDataSource extends BaseDataSource {
 
   @Override
   public long open(DataSpec dataSpec) throws RawResourceDataSourceException {
-    Uri uri = dataSpec.uri;
+    Uri uri = dataSpec.uri.normalizeScheme();
     this.uri = uri;
 
     int resourceId;
@@ -148,10 +148,13 @@ public final class RawResourceDataSource extends BaseDataSource {
       }
     } else {
       throw new RawResourceDataSourceException(
-          "URI must either use scheme "
+          "Unsupported URI scheme ("
+              + uri.getScheme()
+              + "). Only "
               + RAW_RESOURCE_SCHEME
-              + " or "
-              + ContentResolver.SCHEME_ANDROID_RESOURCE,
+              + " and "
+              + ContentResolver.SCHEME_ANDROID_RESOURCE
+              + " are supported.",
           /* cause= */ null,
           PlaybackException.ERROR_CODE_FAILED_RUNTIME_CHECK);
     }

library/datasource/src/test/java/com/google/android/exoplayer2/upstream/ResolvingDataSourceContractTest.java

@@ -68,7 +68,7 @@ public class ResolvingDataSourceContractTest extends DataSourceContractTest {
         new Resolver() {
           @Override
           public DataSpec resolveDataSpec(DataSpec dataSpec) throws IOException {
-            return URI.equals(dataSpec.uri.toString())
+            return URI.equals(dataSpec.uri.normalizeScheme().toString())
                 ? dataSpec.buildUpon().setUri(RESOLVED_URI).build()
                 : dataSpec;
           }

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

@@ -385,6 +385,44 @@ public abstract class DataSourceContractTest {
   }
 
   @Test
+  public void uriSchemeIsCaseInsensitive() throws Exception {
+    ImmutableList<TestResource> resources = getTestResources();
+    Assertions.checkArgument(!resources.isEmpty(), "Must provide at least one test resource.");
+
+    for (int i = 0; i < resources.size(); i++) {
+      additionalFailureInfo.setInfo(getFailureLabel(resources, i));
+      TestResource resource = resources.get(i);
+      @Nullable String scheme = resource.getUri().getScheme();
+      if (scheme == null) {
+        // No scheme for which to check case-insensitivity.
+        continue;
+      }
+      DataSource dataSource = createDataSource();
+      Uri uri =
+          resource
+              .getUri()
+              .buildUpon()
+              .scheme(invertAsciiCaseOfEveryOtherCharacter(scheme))
+              .build();
+      try {
+        long length = dataSource.open(new DataSpec.Builder().setUri(uri).build());
+        byte[] data =
+            unboundedReadsAreIndefinite()
+                ? DataSourceUtil.readExactly(dataSource, resource.getExpectedBytes().length)
+                : DataSourceUtil.readToEnd(dataSource);
+
+        if (length != C.LENGTH_UNSET) {
+          assertThat(length).isEqualTo(resource.getExpectedBytes().length);
+        }
+        assertThat(data).isEqualTo(resource.getExpectedBytes());
+      } finally {
+        dataSource.close();
+      }
+      additionalFailureInfo.setInfo(null);
+    }
+  }
+
+  @Test
   public void resourceNotFound() throws Exception {
     DataSource dataSource = createDataSource();
     assertThrows(IOException.class, () -> dataSource.open(new DataSpec(getNotFoundUri())));

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

@@ -265,7 +265,7 @@ public class FakeDataSet {
   /** Returns a new {@link FakeData} with the given {@code uri}. */
   public FakeData newData(Uri uri) {
     FakeData data = new FakeData(this, uri);
-    dataMap.put(uri, data);
+    dataMap.put(uri.normalizeScheme(), data);
     return data;
   }
 
@@ -278,7 +278,7 @@ public class FakeDataSet {
   /** Returns the data for the given {@code uri}, or {@code defaultData} if no data is set. */
   @Nullable
   public FakeData getData(Uri uri) {
-    @Nullable FakeData data = dataMap.get(uri);
+    @Nullable FakeData data = dataMap.get(uri.normalizeScheme());
     return data != null ? data : defaultData;
   }
 

testutils/src/test/java/com/google/android/exoplayer2/testutil/FakeDataSetTest.java

@@ -51,11 +51,11 @@ public final class FakeDataSetTest {
             .setData(uris[2], testData[3]);
 
     assertThat(fakeDataSet.getAllData().size()).isEqualTo(4);
-    assertThat(fakeDataSet.getData("unseen_uri")).isEqualTo(fakeDataSet.getData((Uri) null));
+    assertThat(fakeDataSet.getData("unseen_uri")).isEqualTo(fakeDataSet.getData("not a real key"));
     for (int i = 0; i < 3; i++) {
       assertThat(fakeDataSet.getData(uris[i]).uri).isEqualTo(uris[i]);
     }
-    assertThat(fakeDataSet.getData((Uri) null).getData()).isEqualTo(testData[0]);
+    assertThat(fakeDataSet.getData("not a real key").getData()).isEqualTo(testData[0]);
     for (int i = 1; i < 4; i++) {
       assertThat(fakeDataSet.getData(uris[i - 1]).getData()).isEqualTo(testData[i]);
     }
@@ -79,7 +79,7 @@ public final class FakeDataSetTest {
             .appendReadError(exception)
             .endData();
 
-    List<Segment> segments = fakeDataSet.getData((Uri) null).getSegments();
+    List<Segment> segments = fakeDataSet.getData("not a real key").getSegments();
     assertThat(segments.size()).isEqualTo(5);
     assertSegment(segments.get(0), testData, 3, 0, null, null);
     assertSegment(segments.get(1), testData, 3, 3, null, null);
@@ -90,7 +90,15 @@ public final class FakeDataSetTest {
     byte[] allData = new byte[6];
     System.arraycopy(testData, 0, allData, 0, 3);
     System.arraycopy(testData, 0, allData, 3, 3);
-    assertThat(fakeDataSet.getData((Uri) null).getData()).isEqualTo(allData);
+    assertThat(fakeDataSet.getData("not a real key").getData()).isEqualTo(allData);
+  }
+
+  @Test
+  public void uriSchemesAreCaseInsensitive() {
+    byte[] data = TestUtil.buildTestData(3);
+    FakeDataSet fakeDataSet = new FakeDataSet().setData("HtTp://example.test/path/to/data", data);
+
+    assertThat(fakeDataSet.getData("hTtP://example.test/path/to/data").getData()).isEqualTo(data);
   }
 
   private static void assertSegment(