参数匹配器的无效使用。 如果此方法使用另一种私有方法，我该如何测试它？

Question

I have method:

public void loadPlatformDependencies() {
    try {
        dependenciesRepository.deleteAll();
        dependenciesRepository.saveAll(pullLastDependencies());
        publisher.publishEvent(new LoadedDependenciesEvent());
    } catch (Exception e) {
        LOGGER.error("Failed to load dependencies", e);
    }
}

And I try to test it:

   @Test
    public void testLoadPlatformDependencies() {
        ArgumentCaptor<Iterable<Dependency>> captor = ArgumentCaptor.forClass(Iterable.class);
        when(dependenciesRepository.saveAll(captor.capture())).thenReturn(any(Iterable.class));
        puller.loadPlatformDependencies();

        verify(dependenciesRepository,times(1)).deleteAll();
        verify(dependenciesRepository, times(1)).saveAll(any(Iterable.class));
        verify(publisher,times(1)).publishEvent(any());

   }

But there is a problem, that method pullLastDependencies() work incorect now. I have a mistake:

Invalid use of argument matchers!
0 matchers expectd, 1 recorded:

Method pullLastDependencies() returns List. Can I test this method without a properly working method pullLastDependencies()? Or maybe I should test this method in another way?

Answer 1

You're using the captor in when() instead of verify() . And you're returning any() (which is just null ) from your mocked method, instead of returning what you want this mock to return. if you don't care about what it returns because you don't use it, then return an empty iterable.

It should be

when(dependenciesRepository.saveAll(any()).thenReturn(Collections.emptyList());
puller.loadPlatformDependencies();

verify(dependenciesRepository).deleteAll();
verify(dependenciesRepository).saveAll(captor.capture());

Answer 2

I think the problem here is that you are using a matcher as a return value in

when(dependenciesRepository.saveAll(captor.capture())).thenReturn(any(Iterable.class));

You should use the matchers to "match" method parameters, and return another structure, like this:

when(dependenciesRepository.saveAll(anyIterable())).thenReturn(Collections.emptyList())

As long as your pullLastDependencies() method doesn't have another dependency, it should work.

Edit: It seems that your pullLastDependencies() has some other dependencies, so you need to mock the call to it. You can achieve this by changing the visibility of the method during the test, so you can mock it, but keep in mind that this is not considered good pratice.

//making private method accessible
Method method = service.getClass().getDeclaredMethod("pullLastDependencies",params);
method .setAccessible(true); 
when(pullLastDependencies()).thenReturn(Collections.emptyList())