Update README.md

Author: bobekos

README.md

@@ -38,9 +38,11 @@ class UserViewModel(private val dao: UserDao) : ViewModel() {
 viewModel.insert(1, "User").subscribeCompletable(this)
 //or with callback
 viewModel.insert(1, "Bobekos").subscribeCompletable(this,
+                    //optional
                     onComplete = {
                         showToast("User inserted")
                     },
+                    //optional
                     onError = {
                         showToast(it.message)
                     })
@@ -63,6 +65,7 @@ viewModel.getFromSingle(1).subscribeSingle(this,
                     onSuccess = {
                         showToast("User ${it.username} loaded")
                     },
+                    //optional
                     onError = {
                         showToast(it.message)
                     })
@@ -85,9 +88,11 @@ viewModel.getFromMaybe(1).subscribeMaybe(this,
                     onSuccess = {
                         showToast("User ${it.username} loaded")
                     },
+                    //optional
                     onError = {
                         showToast(it.message)
                     },
+                    //optional
                     onComplete = {
                         showToast("No user found")
                     })
@@ -115,18 +120,76 @@ viewModel.loadUser().nonNullObserver(this,
                 observer = {
                     showToast("I'm observing ${it.username}")
                 },
+                //optional
                 nullObserver = {
                     showToast("Value is null")
                 })
 ```
 
-## Features
+## Testing
 
-...
+For each reactive source there is a specific test method.
+```kotlin
+liveData.testCompletableSubscribe(...)
+liveData.testMaybeSubscribe(...)
+liveData.testSingleSubscribe(...)
+```
 
-## Testing
+Make sure to include the 'InstantTastExecutorRule' (core-testing) into your tests. Furthermore, the default IoSchedulerHandler (or the scheduler which you used) should be overwritten.
 
-...
+```kotlin
+@RunWith(JUnit4::class)
+class UserViewModelTest {
+    
+    private inline fun <reified T> lambdaMock(): T = Mockito.mock(T::class.java)
+    
+    @get:Rule
+    var rule: TestRule = InstantTaskExecutorRule()
+    
+    private val userDao = mock(UserDao::class.java)
+    private val viewModel = UserViewModel(userDao)
+    
+    @Before
+    fun setup() {
+        RxJavaPlugins.setIoSchedulerHandler {
+            Schedulers.trampoline()
+        }
+    }
+    
+    @Test
+    fun testGetFromSingleSuccess() {
+        val testObject = UserEntity(1, "Bobekos")
+
+        `when`(userDao.getByIdAsSingle(1)).then { Single.just(testObject) }
+
+        val lifecycle = LifecycleRegistry(mock(LifecycleOwner::class.java))
+        lifecycle.handleLifecycleEvent(Lifecycle.Event.ON_RESUME)
+
+        val observer = lambdaMock<(t: UserEntity) -> Unit>()
+
+        viewModel.getFromSingle(1).testSingleSubscribe(lifecycle, onSuccess = observer)
+
+        verify(observer).invoke(testObject)
+    }
+    
+    @Test
+    fun testGetFromSingleError() {
+        val testObject = SQLiteConstraintException()
+
+        `when`(userDao.getByIdAsSingle(1)).then { Single.error<UserEntity>(testObject) }
+
+        val lifecycle = LifecycleRegistry(mock(LifecycleOwner::class.java))
+        lifecycle.handleLifecycleEvent(Lifecycle.Event.ON_RESUME)
+
+        val observer = lambdaMock<(e: Throwable) -> Unit>()
+
+        viewModel.getFromSingle(1).testSingleSubscribe(lifecycle, onError = observer)
+
+        verify(observer).invoke(testObject)
+    }
+```
+
+For more tests look into the sample [app](https://github.com/bobekos/ReactiveLiveData/blob/master/app/src/test/java/com/github/bobekos/rxviewmodelexample/viewmodel/UserViewModelTest.kt)
 
 ## Resources and Credits