@Test
public void shouldPropagateErrorsFromUpstream() throws Exception {

  final Throwable expected = new RuntimeException("expected");
  TestObserver<Integer> observer =
      input.compose(RxConnectables.toTransformer(connectable)).test();
  input.onError(expected);
  observer.awaitTerminalEvent(1, TimeUnit.SECONDS);
  observer.assertError(expected);
}