Demonstration of Dagger 2 per-test Activity injection (if https://github.com/google/dagger/issues/648 is resolved)

MyActivityTest.java

@RunWith(AndroidJUnit4.class)
public class MyActivityTest {

    @Rule public ActivityTestRule<MyActivity> activityTestRule = new ActivityTestRule<>(MyActivity.class, false, false);

    private MyApp myApp;

    @Before public void setup() {
        myApp = (MyApp) InstrumentationRegistry.getTargetContext().getApplicationContext();
    }

    @Test public void mockInjection() throws Exception {
        // Mock the injector and set it in the App.
        myApp.dispatchingAndroidInjector = new Injector();

        activityTestRule.launchActivity(new Intent(myApp, MyActivity.class));
        MyActivity myActivity = activityTestRule.getActivity();

        // Check things got injected correctly.
        Assert.assertEquals("test-singleton-value", myActivity.singletonString);
        Assert.assertEquals("test-per-activity-value", myActivity.perActivityString);
    }

    // Can't actually do this since DispatchingAndroidInjector isn't mockable (yet).
    public static class Injector implements DispatchingAndroidInjector<MyActivity> {

        @Override
        public void inject(MyActivity instance) {
            instance.singletonString = "test-singleton-value";
            instance.perActivityString = "test-per-activity-value";
        }
    }
}

@vaughandroid is "DispatchingAndroidInjector" is still not mockable..?