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androiddagger-2android-junit

Mocking dependency error with AndroidJunitRunner and Dagger2

I am trying to mock dependencies like what is suggested in https://artemzin.com/blog/how-to-mock-dependencies-in-unit-integration-and-functional-tests-dagger-robolectric-instrumentation/

Unfortunately I can't get past the following error when I run my AndroidJunit4 test :

Test running failed: Unable to find instrumentation info for: ComponentInfo{com.fisincorporated.aviationweather.test/android.support.test.runner.AndroidJUnitRunner}

I tried various SO solutions that were not Android Studio version dependent with no luck

My app level gradle code snippet is: 

android {
   ...
defaultConfig {
     ...
    testInstrumentationRunner "com.fisincorporated.aviationweather.app.OverrideApplicationTestRunner"
}
...
}

My OverrideApplicationTestRunner is:

public class OverrideApplicationTestRunner extends AndroidJUnitRunner {
@Override
@NonNull
public Application newApplication(@NonNull ClassLoader cl,
                                  @NonNull String className,
                                  @NonNull Context context)
        throws InstantiationException,
        IllegalAccessException,
        ClassNotFoundException {
    return Instrumentation.newApplication(WeatherApplicationTest.class, context);
}
}

WeatherApplicationTest

public class WeatherApplicationTest extends WeatherApplication {

@Override
protected void createDaggerInjections() {
    component = DaggerDiComponent.builder()
            .appModule(new AppModule(this) {
                @Override
                public String providesAppSharedPreferencesName() {
                    return "SHARED_AIRPORT_FUNCTIONAL_TEST";
                }

                public Retrofit provideAppRetrofit() {
                    return new AppRetrofit(new MockInterceptor()).getRetrofit();
                }
            })
            .build();
    component.inject(this);
}
}

And AirportWeatherActivityTest

@RunWith(AndroidJUnit4.class)
public class AirportWeatherActivityTest {

    @Rule
    public ActivityTestRule<AirportWeatherActivity> mActivityRule =
            new ActivityTestRule<>(AirportWeatherActivity.class, true, false);

    @Test
    public void someTest() {
        Context targetContext = InstrumentationRegistry.getTargetContext();
        Intent intent = new Intent(targetContext, AirportWeatherActivity.class);

        mActivityRule.launchActivity(intent);
        assertThat(mActivityRule.getActivity().airportWeatherViewModel.airportWeatherList.size(),is(0));

    }
}

androidTest directory structure is below:

enter image description here

I have found that if I run the following test, it works, i.e. I see that WeatherApplicationTest is being executed. So it would seem that testInstrumentationRunner is finding my OverrideApplicationTestRunner. 

@RunWith(AndroidJUnit4.class)
public class ExampleInstrumentedTest {
@Test
public void useAppContext() throws Exception {
    // Context of the app under test.
    Context appContext = InstrumentationRegistry.getTargetContext();

    assertEquals("com.fisincorporated.aviationweather", appContext.getPackageName());
}
}

So is problem caused by using an ActivityTestRule?

P.S. I neglected to say I am a newbie on testing so my apologizes if I am missing something obvious.

Solution

  • Switching android plugin version to 2.2.3 and then back to 2.3.0 back, cleaning project and building fixes the issue.