@Test public void onEvent_skipsErrorWhenSet() {

  setEventType(RequestEvent.Type.FINISHED);
  setBaseUri("/");
  when(request.getProperty(SpanCustomizer.class.getName())).thenReturn(span);
  Exception error = new Exception();
  when(requestEvent.getException()).thenReturn(error);
  when(request.getProperty("error")).thenReturn("madness");
  listener.onEvent(requestEvent);
  verify(request).getProperty(SpanCustomizer.class.getName());
  verify(request).getProperty("error");
  verify(request).getUriInfo();
  verify(request).setProperty("http.route", ""); // empty means no route found
  verifyNoMoreInteractions(request); // no setting of error
}