mocking methods that depend on parameters passed to them

[sarimmehdi]

I am new to Mockito so I apologize if I don't get the general philosophy of this library. Documentation on this for the java version of mockito also doesn't really explain how to mock methods where the returned result depends on the parameters passed to the method. Below is the method I am trying to mock:

override suspend fun getComics(
    numsOfComicsToLoad: List<Int>,
    loadFromDatabase: Boolean
): Flow<Resource<List<Comic>>> = flow {
    emit(Resource.Loading())
    val comics = if (loadFromDatabase) {
        comicsInDatabase.filter { comic -> comic.num in numsOfComicsToLoad }
    } else {
        comicsInApi.filter { comic -> comic.num in numsOfComicsToLoad }
    }
    emit(Resource.Success(comics))
}

here's my attempt at trying to mock the above method (it is part of the repository class)

repository = mock {
    onBlocking { getComics(anyArray<Int>().toList(), any()) } doReturn flow {
        emit(Resource.Loading())
        // what do I do now????
    }
}

Any help regarding this would be appreciated

[TimvdLippe]

You can use Answer to implement custom logic: https://stackoverflow.com/questions/44066993/using-mockito-doanswer-in-kotlin

[sarimmehdi]

I am adding my code here for anyone else running into the same problem:

repository = mock {
    onBlocking { getAllComics() } doReturn flow {
        emit(Resource.Loading())
        emit(Resource.Success(comicsInDatabase))
    }
    onBlocking { getComics(any(), any()) } doAnswer {
        flow {
            val numsOfComicsToLoad = it.getArgument(0) as List<Int>
            val loadFromDatabase = it.getArgument(1) as Boolean
            emit(Resource.Loading())
            val comics = if (loadFromDatabase) {
                comicsInDatabase.filter { comic -> comic.num in numsOfComicsToLoad }
            } else {
                comicsInApi.filter { comic -> comic.num in numsOfComicsToLoad }
            }
            emit(Resource.Success(comics))
        }
    }