class SignInViewModelTest {
    /**
     * Tests if clickSignIn calls expected method from Repository. Currently, that's its only task.
     */
    @Test
    fun testclcikSignIn() {
        val mockContext = Mockito.mock(Context::class.java)
        val mockRepository = Mockito.mock(Repository::class.java)
        val input = "inputHere"

    // return something to be expected
        Mockito.`when`(mockRepository.signInOperation(mockContext, input))
                .thenReturn(Single.just(Intent()))

    val origRepository = ReflectionHelpers.getStaticField<Repository>(
                Repository::class.java, "instance")
        ReflectionHelpers.setStaticField(Repository::class.java, "instance", mockRepository)

    // actual test – check output type and verify a Repository operation was called
        assertTrue("Method return type wrong", viewModel.clickSignIn.(mockContext, input) is Single<Intent>)
        verify(mockRepository, times(1)).signInOperation(mockContext, input)

        ReflectionHelpers.setStaticField(Repository::class.java, "instance",
                origRepository)
    }
}