Mocking modules that depend on the activity

[tschuchortdev]

In my activity I have a module that depends on the activity itself. How would I mock this with DaggerMock?

I have tried instantiating it in the test like I would any other module, but unfortunately the activity is only available after the rules are run:

        @get:Rule
	private val intentsRule = IntentsTestRule(HomeActivity::class.java)

	private val activity by lazy { intentsRule.activity!! }

	@get:Rule
	val daggerRule = DaggerMock.rule<HomeComponent>(HomeModule(), ActivityModule(activity)) {
		set { activity.component = it }
	}

would throw a nullptr exception. In this specific case I only need to mock objects that are in the HomeModule, so I guess I might be able to just pass in a mocked ActivityModule. But who knows if this will work and in the future I might have to use stuff inside the ActivityModule as well.

[fabioCollini]

Usually you shouldn't pass the ActivityModule in the rule, however it depends on how you have organized your code. Here you can find an example when a presenter defined in an activity module is mocked (it works if you are using subcomponents).

[tschuchortdev]

How else would I be able to mock the presenter when it's in the HomeComponent/HomeModule, not the AppComponent?

I have tried just replacing the AppComponent like in the example you linked, but I'm getting runtime errors along the lines of "@Provides annotated method can not return null". Maybe it's because I'm not using subcomponents? My components generally look like this:

@PerActivity
@Component(
		modules = arrayOf(HomeModule::class, ActivityModule::class),
		dependencies = arrayOf(AppComponent::class))
interface HomeComponent : AppComponent {
	fun exposePresenter(): HomeContract.Presenter

	fun inject(activity: HomeActivity)
}

[fabioCollini]

Unfortunately you can mock the presenter using DaggerMock only if you use subcomponents or if you define it in the main component. However it's hard to replace it with a mock even without DaggerMock.