Dagger2, tests fail because lateinit not initializ...

# android

[Nikola Milovic]

Dagger2, tests fail because lateinit not initialized

@Module(includes = [TestApplicationModuleBinds::class])
object TestApplicationModule {
    @set:Inject
    lateinit var mockQuoteDataSource : MockQuoteDataSource

class MockQuoteDataSource @Inject constructor(jsonNetworkService: JsonNetworkService) : TestQuoteRemoteDataSource(jsonNetworkService.apiService) {

I get the error

kotlin.UninitializedPropertyAccessException: lateinit property mockQuoteDataSource has not been initialized

[tseisel]

Why are you injecting to a field in a module object class ?

[Nikola Milovic]

@Test
    fun willDisplayQuote() {
        TestApplicationModule.mockQuoteDataSource.mockSuccess(listOf(Quote("Expected Author", "Expected Quote")))

I'm trying to use the mockQuoteDataSource in my tests, should i move it all together somewhere else?

[tseisel]

You should not inject into `Module`s. In fact, Dagger modules should only be used to provide types that you don't own, for example the application Context or SharedPreferences, and you should avoid instance fields in modules (especially if those are object). I think you need a Component.
Depending on the type of test you are writing, you should proceed the following :
- Unit Tests : just don't use Dagger. Instantiate the class under test yourself, passing its dependencies as mocks or fakes.
- Integration Tests : create a Dagger Component responsible for instantiating the class under test with its real dependencies. This component should reference alternative version of the production `Module`s, for example simulating a network API or using an in-memory database. More information here : https://dagger.dev/testing

[Nikola Milovic]

Thank you, I will check it out! I've been struggling for a while with this