Medium Post 3. RestaurantsRepositoryTest

RestaurantsRepositoryTest.kt

@RunWith(AndroidJUnit4::class)
class RestaurantsRepositoryTest {

    @Rule
    @JvmField
    var instantExecutor = InstantTaskExecutorRule()

    @Mock
    private lateinit var observer: Observer<Resource<List<Restaurant>>>

    private lateinit var mockWebServer: MockWebServer

    private lateinit var database: Database
    private lateinit var utils: Utils
    private lateinit var restaurantsDao: RestaurantsDao
    private lateinit var repository: RestaurantsRepository
    private lateinit var appExecutors: AppExecutors
    private lateinit var retrofit: Retrofit
    private lateinit var webService: WebService

    companion object {
        val TIMEOUT = 1000L
    }

    @Before
    fun setup() {
        MockitoAnnotations.initMocks(this)
        val context = InstrumentationRegistry.getTargetContext()
        database = Room.inMemoryDatabaseBuilder(context, Database::class.java).allowMainThreadQueries().build()
        restaurantsDao = database.restaurantsDao()
        utils = Utils(context)
        appExecutors = AppExecutors()

        mockWebServer = MockWebServer()
        mockWebServer.start()

        retrofit = Retrofit.Builder()
                .addConverterFactory(MoshiConverterFactory.create())
                .baseUrl(mockWebServer.url("/").toString())
                .client(OkHttpClient())
                .build()
        webService = retrofit.create<WebService>(WebService::class.java)
        repository = RestaurantsRepository(webService, restaurantsDao, utils, appExecutors)
    }

    @After
    fun tearDown() {
        mockWebServer.shutdown()
    }   
   
   // ...
   
   /**
     * Case 2: receive item with invalid name.
     * Expected result: Resource(status = SUCCESS, data = [], error = null)
     */
    @Test
    fun itemWithInvalidNameTest() {
        //given
        val content = this.javaClass.classLoader.getResource("get-restaurants-cases/invalid-name.json").readText(Charset.forName("UTF-8"))
        mockWebServer.enqueue(MockResponse()
                .setResponseCode(200)
                .setBody(content))
        //when
        repository.getRestaurants().observeForever(observer)
        //then
        verify(observer, timeout(TIMEOUT)).onChanged(ArgumentMatchers.refEq(Resource.success(emptyList())))
    }
    
}