Test

gistfile1.txt

@RunWith(RobolectricTestRunner::class)
@Config(sdk = [28])
class ExchangeRatesRepositoryImplTest : KoinTest {
    private val mockWebServer = MockWebServer()

    lateinit var repo: ExchangeRateRepository

    private val api: ExchangeRateAPI by inject()

    @get:Rule
    val koinTestRule = KoinTestRule.create {
        printLogger(Level.DEBUG)
        modules(dataModules + listOf(fakeContext))
    }

    @Before
    fun setup() {
        mockWebServer.start()
        declare {
            val gson = GsonBuilder()
                .serializeNulls()
                .create()

            Retrofit.Builder()
                .baseUrl(mockWebServer.url("/"))
                .addConverterFactory(GsonConverterFactory.create(gson))
                .client(get())
                .build()
        }
        repo = ExchangeRatesRepositoryImpl(api)
    }

    @After
    fun tearDown() {
        mockWebServer.shutdown()
    }

    @Test
    fun `test exchange rates are fetched successfully`() = runBlocking {
        mockWebServer.enqueue(
            MockResponse().setResponseCode(HttpURLConnection.HTTP_OK).setBody(getJson("exchangerates.json"))
        )
        val result: NetworkResult<ExchangeRateDomainModel> = repo.fetchExchangeRates()
        MatcherAssert.assertThat(result, CoreMatchers.instanceOf(NetworkResult.Success::class.java))
    }
}