单元测试MVP使用mockito与事件监听器

Question

Android Studio 2.1.2

我想测试实际调用LoginModelImp中的回调onUsernameError,onPasswordError和onSuccess.我不确定如何测试事件监听器.但是,测试失败,因为从不调用这些函数.我用mockito嘲笑他们并试图验证它们.

到目前为止这是我的代码.

演示者界面

public interface LoginPresenterContract<LoginFragmentViewContract> {
    void validateCredentials();

    void attachView(LoginFragmentViewContract view);
    void detachView();
}

演示者实施

public class LoginPresenterImp implements LoginPresenterContract<LoginFragmentViewContract>, LoginModelContract.OnLoginCompletedListener {

    private LoginModelContract mLoginModelContract;
    private LoginFragmentViewContract mLoginFragmentView;

    public LoginPresenterImp(LoginModelContract loginModelContract) {
        mLoginModelContract = loginModelContract;
    }

    /*
     * LoginPresenterContact - implementation
     */
    @Override
    public void attachView(LoginFragmentViewContract view) {
        mLoginFragmentView = view;
    }

    @Override
    public void detachView() {
        mLoginFragmentView = null;
    }

    @Override
    public void validateCredentials() {
        if(mLoginModelContract != null) {
            mLoginModelContract.login(
                    mLoginFragmentView.getUsername(),
                    mLoginFragmentView.getPassword(),
                    LoginPresenterImp.this);
        }
    }

    /*
     * LoginModelContract.OnLoginCompletedListener - implementation
     */
    @Override
    public void onUsernameError() {
        if(mLoginFragmentView != null) {
            mLoginFragmentView.onLoginFailed("Incorrect username");
        }
    }

    @Override
    public void onPasswordError() {
        if(mLoginFragmentView != null) {
            mLoginFragmentView.onLoginFailed("Incorrect password");
        }
    }

    @Override
    public void onSuccess() {
        if(mLoginFragmentView != null) {
            mLoginFragmentView.onLoginSuccess();
        }
    }
}

模型界面

public interface LoginModelContract {
    interface OnLoginCompletedListener {
        void onUsernameError();
        void onPasswordError();
        void onSuccess();
    }
    void login(String username, String password, OnLoginCompletedListener onLoginCompletedListener);
}

模型实施

public class LoginModelImp implements LoginModelContract {
    /* Testing Valid username and passwords */
    private static String validUsername = "steve";
    private static String validPassword = "1234";

    @Override
    public void login(final String username,
                      final String password,
                      final OnLoginCompletedListener onLoginCompletedListener) {

        boolean hasSuccess = true;
        if(TextUtils.isEmpty(username) || !username.equals(validUsername)) {
        /* TEST onUsernameError() */
            onLoginCompletedListener.onUsernameError();
            hasSuccess = false;
        }

        if(TextUtils.isEmpty(password) || !password.equals(validPassword)) {
        /* TEST onPasswordError() */
            onLoginCompletedListener.onPasswordError();
            hasSuccess = false;
        }

        if(hasSuccess) {
        /* TEST onSuccess() */
            onLoginCompletedListener.onSuccess();
        }
    }
}

与Mockito进行JUnit4测试

public class LoginPresenterImpTest {
    private LoginFragmentViewContract mMockViewContract;
    private LoginModelContract mMockModelContract;
    private LoginModelContract.OnLoginCompletedListener mMockOnLoginCompletedListener;
    private LoginPresenterContract<LoginFragmentViewContract> mLoginPresenterContract;

    @Before
    public void setUp() throws Exception {
        mMockViewContract = Mockito.mock(LoginFragmentViewContract.class);
        mMockModelContract = Mockito.mock(LoginModelContract.class);
        mMockOnLoginCompletedListener = Mockito.mock(LoginModelContract.OnLoginCompletedListener.class);
        mLoginPresenterContract = new LoginPresenterImp(mMockModelContract);
        mLoginPresenterContract.attachView(mMockViewContract);
    }

    @Test
    public void shouldSuccessWithValidCredentials() {
        when(mMockViewContract.getUsername()).thenReturn("steve");
        when(mMockViewContract.getPassword()).thenReturn("1234");

        mLoginPresenterContract.validateCredentials();

        verify(mMockViewContract, times(1)).getUsername();
        verify(mMockViewContract, times(1)).getPassword();

        verify(mMockOnLoginCompletedListener, times(1)).onSuccess();

        verify(mMockOnLoginCompletedListener, never()).onPasswordError();
        verify(mMockOnLoginCompletedListener, never()).onUsernameError();
    }
}

有没有办法测试这个实现？

非常感谢任何建议,

Answer 1

测试类LoginPresenterImpTest是关于类的测试LoginPresenterImp，它应该仅使用其实际实现及其协作者的模拟。该类LoginModelContract.OnLoginCompletedListener是 的合作者LoginModelImp，因此在像您这样设计良好的纯单元测试中LoginPresenterImp，它从未被调用是完全正常的。我建议的解决方案是单独测试 LoginModelImp：

public class LoginModelImpTest {

    private LoginModelContract.OnLoginCompletedListener mMockOnLoginCompletedListener;
    private LoginModelImp loginModelImp;

    @Before
    public void setUp() throws Exception {
        mMockOnLoginCompletedListener = Mockito.mock(LoginModelContract.OnLoginCompletedListener.class);
        loginModelImp = new LoginModelImp();
    }

    @Test
    public void shouldSuccessWithValidCredentials() {

        loginModelImp.login("steve", "1234", mMockOnLoginCompletedListener);;

        verify(mMockOnLoginCompletedListener, times(1)).onSuccess();

        verify(mMockOnLoginCompletedListener, never()).onPasswordError();
        verify(mMockOnLoginCompletedListener, never()).onUsernameError();
    }
}

或者，您必须使用LoginModelImp您的实际实现LoginPresenterImpTest并监视您的侦听器（即演示者本身）或配置模拟以使它们调用侦听器。这是一个例子，但我不会使用这个：

public class LoginPresenterImpTest {
    private LoginFragmentViewContract mMockViewContract;
    private LoginModelContract mModelContract;
    private LoginModelContract.OnLoginCompletedListener mMockOnLoginCompletedListener;
    private LoginPresenterContract<LoginFragmentViewContract> mLoginPresenterContract;

    @Before
    public void setUp() throws Exception {
        mMockViewContract = Mockito.mock(LoginFragmentViewContract.class);
        mModelContract = new LoginModelImp();
        LoginPresenterImp spyPresenterImp = Mockito.spy(new LoginPresenterImp(mModelContract));
        mLoginPresenterContract = spyPresenterImp;
        mMockOnLoginCompletedListener = spyPresenterImp;
        mLoginPresenterContract.attachView(mMockViewContract);
    }

    @Test
    public void shouldSuccessWithValidCredentials() {
        when(mMockViewContract.getUsername()).thenReturn("steve");
        when(mMockViewContract.getPassword()).thenReturn("1234");

        mLoginPresenterContract.validateCredentials();

        verify(mMockViewContract, times(1)).getUsername();
        verify(mMockViewContract, times(1)).getPassword();

        verify(mMockOnLoginCompletedListener, times(1)).onSuccess();

        verify(mMockOnLoginCompletedListener, never()).onPasswordError();
        verify(mMockOnLoginCompletedListener, never()).onUsernameError();
    }
}