MockK协程响应无法响应

Question

Trying to dig deeper into using MockK where a coroutine is involved. I have this test:

class UserDataUseCaseTest {

    @MockK
    val dataFetcherService: DataFetcherService = mockk()

    @MockK
    val userData: UserData = mockk()

    @ExperimentalCoroutinesApi
    @Test
    fun `fetching salt populates user data salt value`() = runBlockingTest {
        MockKAnnotations.init(this)
        val userDataUseCase = UserDataUseCase(mockk(), mockk(), mockk())
        every { userData.user_name } returns FAKE_USER
        coEvery { dataFetcherService.getSaltForUser(FAKE_USER) } returns SALT_RESPONSE
        userDataUseCase.getSaltForUser(userData)
        assertEquals(SALT, userData.salt)
    }

    companion object {
        private const val FAKE_USER = "fake_user"
        private const val SALT = "salt"
        private val SALT_RESPONSE = SaltResponse(
            result = "",
            title = "",
            message = "",
            salt = SALT,
            auth_code = "auth_code",
            userMustChangePassword = false
        )
    }
}

This fails with the following error:

io.mockk.MockKException: no answer found for: DataFetcherService(#4).getSaltForUser(fake_user, continuation {})

The method that I am trying to test looks like this:

@VisibleForTesting
suspend fun getSaltForUser(userData: UserData) {
    val saltResponse = dataFetcherService.getSaltForUser(userData.user_name)

    with (userData) {

        salt = if (saltResponse.salt.isEmpty())
            KeyChainWrapper().generateRandomString(KeyChainWrapper.SALT_LEN)
        else saltResponse.salt

        authCode = saltResponse.auth_code
        userMustChangePassword = saltResponse.userMustChangePassword
    }
}

Why am I not getting an answer for the getSaltForUser() call? Thanks for any help.

Answer 1

From the look of that sample code the class under test is not using the same mock as the one defined in the test:

val userDataUseCase = UserDataUseCase(mockk(), mockk(), mockk())

should be something like

val userDataUseCase = UserDataUseCase(dataFetcherService, mockk(), mockk())

depending on which parameter the DataFetcherService should be