android - "Mockito 0 matchers expected, 3 recorded"- 为什么需要 0 个匹配器？

Question

以前有人问过这个问题，但现有的答案并不完全适用于我的情况。

我想测试 submitCode() 方法:

public class VerificationCodeViewModel{

    //Input
    public final ObservableField<String> verificationCode           = new ObservableField<>();

    //Output
    public final ObservableField<String> requestError               = new ObservableField<>();
    public final ObservableBoolean loading                          = new ObservableBoolean();
    public final ObservableField<LoginCredentials> loginCredentials = new ObservableField<>();

    @NonNull private final Context context;
    @NonNull private final UnverifiedUser unverifiedUser;
    @NonNull private final CampaignRepository campaignRepository;
    @NonNull private final AccountRepository accountRepository;
    @NonNull private final VerificationCodeNavigator navigator;

    public VerificationCodeViewModel(@NonNull Context context,
                                     @NonNull UnverifiedUser unverifiedUser,
                                     @NonNull CampaignRepository campaignRepository,
                                     @NonNull AccountRepository accountRepository,
                                     @NonNull VerificationCodeNavigator navigator) {

        this.context = context;
        this.unverifiedUser = unverifiedUser;

        this.campaignRepository = campaignRepository;
        this.accountRepository = accountRepository;
        this.navigator = navigator;
    }

    public void submitCode() {

        loading.set(true);

        String sourceCampaign = null;
        if (campaignRepository.getCampaign() != null) {
            sourceCampaign = campaignRepository.getCampaign().getSource();
        }

        this.accountRepository.verifyMobileNumber(
                this.unverifiedUser,
                this.verificationCode.get(),
                sourceCampaign,
                new AccountDataSource.VerifyMobileNumberCallback() {
                    @Override
                    public void onVerificationSuccess(UnverifiedUser.Entity entity) {
                        loading.set(false);
                        loginCredentials.set(createLoginCredentials());
                        navigator.finishActivity(true);
                    }

                    @Override
                    public void onVerificationFailure(@Nullable String message) {
                        loading.set(false);
                        requestError.set(message);
                    }
                }
        );
    }
}

我有以下测试用例:

public class VerificationCodeViewModelTests {

    private VerificationCodeViewModel viewModel;

    @Mock private Context context;

    @Mock private UnverifiedUser unverifiedUser;

    @Mock private CampaignRepository campaignRepository;

    @Mock private AccountRepository accountRepository;

    @Mock private VerificationCodeNavigator navigator;

    @Mock private ArgumentCaptor<AccountDataSource.VerifyMobileNumberCallback> verifyMobileNumberCallbackCaptor;


    @Before
    public void setupVerificationCodeViewModel(){

        MockitoAnnotations.initMocks(this);

        viewModel = new VerificationCodeViewModel(
                context,
                unverifiedUser,
                campaignRepository,
                accountRepository,
                mock(VerifyMobileNumberActivity.class)//navigator
        );
    }

    @Test
    public void testSubmitCode(){

        viewModel.verificationCode.set(VERIFICATION_CODE);
        viewModel.submitCode();

        assertTrue(viewModel.loading.get());

        verify(accountRepository).verifyMobileNumber(
                eq(unverifiedUser),//line 132
                eq(VERIFICATION_CODE),//line 133
                eq(CAMPAIGN_SOURCE),//line 134
                verifyMobileNumberCallbackCaptor.capture());//line 135

        UnverifiedUser.Entity entity = mock(UnverifiedUser.Entity.class);
        when(entity.getId()).thenReturn(ENTITY_ID);

        verifyMobileNumberCallbackCaptor.getValue().onVerificationSuccess(entity);

        assertFalse(viewModel.loading.get());
        assertEquals(viewModel.loginCredentials.get().getUsername(),UNVERIFIED_USER_EMAIL);
        assertEquals(viewModel.loginCredentials.get().getPassword(),UNVERIFIED_USER_PASSWORD);

        verify(navigator).finishActivity(true);
    }
}

当我验证 accountRepository.verifyMobileNumber 被调用时，我收到以下错误:

org.mockito.exceptions.misusing.InvalidUseOfMatchersException: Invalid use of argument matchers! 0 matchers expected, 3 recorded: -> at ...testSubmitCode(VerificationCodeViewModelTests.java:132) -> at ...testSubmitCode(VerificationCodeViewModelTests.java:133) -> at ...testSubmitCode(VerificationCodeViewModelTests.java:134)

This exception may occur if matchers are combined with raw values: //incorrect: someMethod(anyObject(), "raw String"); When using matchers, all arguments have to be provided by matchers. For example: //correct: someMethod(anyObject(), eq("String by matcher"));

For more info see javadoc for Matchers class.

at ...VerificationCodeViewModelTests.testSubmitCode(VerificationCodeViewModelTests.java:135)

我不明白的是为什么它说 0 matches expected？其他答案建议将 eq(..) 替换为 any(...) 或 isA(..)。首先，我认为这不适用，因为错误是一开始就没有匹配器；其次，我已经尝试过了，但问题仍然存在。

如果有人能解释为什么需要 0 个匹配器以及如何解决这个问题，我将不胜感激。

更新

AccountRepository.verifyMobileNumber() 的实现是:

AccountRepository.java

public class AccountRepository implements AccountDataSource {
    @Override
    public void verifyMobileNumber(@NonNull UnverifiedUser unverifiedUser, 
                                   @NonNull String verificationCode, 
                                   @Nullable String sourceCampaign, 
                                   @NonNull VerifyMobileNumberCallback callback) {
        this.remoteSource.verifyMobileNumber(unverifiedUser, verificationCode, sourceCampaign, callback);
    }
}

AccountRemoteDataSource.java

public class AccountRemoteDataSource implements AccountDataSource {

    @Override
    public void verifyMobileNumber(@NonNull UnverifiedUser unverifiedUser,
                                   @NonNull String verificationCode,
                                   @Nullable String sourceCampaign,
                                   @NonNull final VerifyMobileNumberCallback callback) {

        accountService().verifyMobileNumber(/*params*/).enqueue(new Callback() {
            @Override
            public void onResponse(Response response, Retrofit retrofit) {
                try{
                    //parse response
                    callback.onVerificationSuccess(entity);
                } catch (Exception e) {
                    callback.onVerificationFailure(e.getMessage());
                }
            }

            @Override
            public void onFailure(Throwable t) {
                callback.onVerificationFailure(t.getMessage());
            }
        });
    }
}

Answer 1

哈哈哈，找到了!您正在使用 @Mock ArgumentCaptor在测试文件的第六个带注释的字段中出错。

@Mock private ArgumentCaptor<AccountDataSource.VerifyMobileNumberCallback>
    verifyMobileNumberCallbackCaptor;

Mockito 没有对自己的基础设施进行特殊封装，因此它没有发现您正在尝试模拟 Mockito 本身这一事实。通过调用方法 ArgumentCaptor.capture()在 verify 中间调用，Mockito 假定您实际上是在尝试验证对 capture 的调用.

尽管语法巧妙，Mockito 实际上只是一个状态机，在这里调用 verify(...)开始验证，每次调用匹配器都会推送匹配器描述 onto an internal stack ，然后下一次调用 Mockito 模拟会触发验证。 Mockito 在参数匹配器堆栈上看到三个匹配器，用于对 capture 的零参数调用。 .这就是为什么记录了 3 个匹配器，而预期为 0 个。

将该注释切换为 @Captor 你应该可以开始了。