使用Retrofit / RxJava / Roboletric和Mockito进行Android单元测试

Question

我试图用Robolectric和Mockito写一个单元测试。我有一个改造可观察的，我想用模拟回应进行测试。我尝试了link here

之类的东西

但我得到了java.lang.NullPointerException。这是我的代码示例：

 private MainActivity mainActivity;

  @Mock
  private FoursquareCalls mockApi;

  @Captor
  private ArgumentCaptor<Action1<FoursquareListResponse>> cb;

 @Before
  public void setup() {
    MockitoAnnotations.initMocks(this);

    ActivityController<MainActivity> controller = Robolectric.buildActivity(MainActivity.class);
    mainActivity = controller.get();

    controller.create();
  }


@Test
  public void shouldFillAdapterWithReposFromApi() throws Exception {
    mockApi.getListFoodTrucks(Mockito.anyString(), Mockito.anyString(), Mockito.anyString(),
        Mockito.anyString(), Mockito.anyString(), Mockito.anyString());

    Mockito.verify(mockApi).getListFoodTrucks(Mockito.anyString(), Mockito.anyString(), Mockito
        .anyString(), Mockito.anyString(), Mockito.anyString(), Mockito.anyString())
        .subscribe(cb.capture());

    SearchFragment searchFragment = (SearchFragment) mainActivity.getFragmentManager().findFragmentById(R.id
        .fragment_container);

    FoursquareListResponse testRespo = new FoursquareListResponse();
    testRespo.foodtruckReponse = new FoodTruckResponseModel();
    testRespo.foodtruckReponse.listFoodtruck = new ArrayList<>();
    testRespo.foodtruckReponse.listFoodtruck.add(new FoodTruckResponseModel());
    testRespo.foodtruckReponse.listFoodtruck.add(new FoodTruckResponseModel());



    cb.getValue().call(testRespo);
    assertEquals(searchFragment.getAdapter(), 2);
  }

当我呼叫.subscribe(cb.capture())时，出现空指针异常。 我以为我能够捕获subsribe()内的调用并使用虚拟对象进行测试。我想我误解了一些东西，但不确定哪个部分：/。