@Test
public void testResponseNotify() {

  tracedCallable.call("test", responseObserver, callContext);
  MockServerStreamingCall<String, String> innerCall = innerCallable.popLastCall();
  innerCall.getController().getObserver().onResponse("response1");
  innerCall.getController().getObserver().onResponse("response2");
  assertThat(responseObserver.popNextResponse()).isEqualTo("response1");
  assertThat(responseObserver.popNextResponse()).isEqualTo("response2");
  verify(tracer, times(2)).responseReceived();
}