UserPresenterTest.java

@Test
public void saveUsername_revealsUsersPlace_onSuccess() {
    User user = createUser(USER_ID, A_USERNAME);
    givenDelegate(userApiResourceDelegate)
            .succeed().withResult(null) // <-- This is because the result has type Void
            .when().saveUser(eq(USER_ID), same(user));
    PlaceRequest placeRequestToGoAfterSave = new PlaceRequest.Builder()
            .nameToken(NameTokens.USERS).build();
            
    presenter.saveUser(user);
    
    verify(placeManager).revealPlace(placeRequestToGoAfterSave);
}

@Test
public void saveUsername_delegatesToService() {
    User user = createUser(USER_ID, A_USERNAME);
    
    presenter.saveUser(user);
    
    verify(userApi).saveUser(eq(USER_ID), same(user));
}