painless-dagger-viewmodelfactory.kt

class FakeViewModelFactory(private val testviewModel: ViewModel) : ViewModelProvider.Factory {
    override fun <T : ViewModel?> create(modelClass: Class<T>) = testviewModel as T
}
​
class FragFactoryFake(private val viewModel: ViewModel) : FragmentFactory() {
        override fun instantiate(classLoader: ClassLoader, className: String): Fragment {
            val fakeViewModelFactory = FakeViewModelFactory(viewModel)
            return MainFragment(fakeViewModelFactory)
        }
}