[FIXED] How should Mockito be used during JUnit4 Testing

Issue

I'm trying to test my use case through Mockito, but it doens't seem to work very well. This is my use case that I wanna test:

class GetStudentsUseCase @Inject constructor(private val studentRepository: StudentRepository) {
    suspend fun execute():Result<List<Student>> = studentRepository.getStudents()
}

Then, I created GetStudentsUseCaseTest that looks like this:

class GetStudentsUseCaseTest {

    private lateinit var cut: GetStudentsUseCase
    private var reservationList = listOf(
        Student("Max", "122d"),
        Student("Steven", "012s")
    )

    @Before
    fun setUp() {
        val fakeStudentRepository = Mockito.mock(StudentRepository::class.java)
        cut = GetStudentsUseCase(fakeStudentRepository)
    }

    @Test
    suspend fun test_name() {
        Mockito.`when`(cut.execute()).thenReturn(Result.success(reservationList))
    }
}

What should I put inside the test_name method?

Edit: answer with solution

Solution

@OptIn(ExperimentalCoroutinesApi::class)
class GetStudentsUseCaseTest {

    private lateinit var cut: GetStudentsUseCase
    @Mock
    private lateinit var repository: StudentRepository
    private var reservationList = listOf(
        Student("Max", "122d"),
        Student("Steven", "012s")
    )

    @Before
    fun setUp() {
        MockitoAnnotations.initMocks(this)
        cut = GetStudentsUseCase(repository)
    }

    @Test
    fun test_name() = runTest {
        Mockito.`when`(repository.getStudents()).thenReturn(Result.success(reservationList))
        val result = cut.execute()
        assertEquals(result, Result.success(reservationList))
    }
}

Answered By - Jonathan
Answer Checked By - Mildred Charles (JavaFixing Admin)