@Test public void lightService_requestFavourites() { List<LightModel> lights = new ArrayList<>(); mockClient(); when(lightRepository.findFavourites()).thenReturn(Observable.just(lights)); TestSubscriber<List<LightModel>> tester = new TestSubscriber<>(); lightService.requestFavourites().subscribe(tester); tester.assertValue(lights); tester.assertCompleted(); tester.assertNoErrors(); }