assertThrows(IOException.class, () -> new TestByteSource(new byte[10]).copyTo(failSink));
    assertTrue(failSink.wasStreamClosed());
  }

  public void testClosesOnErrors_writingFromInputStreamThatThrows() throws IOException {
    TestByteSink okSink = new TestByteSink();
    TestInputStream in = new TestInputStream(new ByteArrayInputStream(new byte[10]), READ_THROWS);