Unit testing while using Dagger 2 (Robolectric and Mockito)

I'm trying to write some tests for fragments which have fields annotated with @Inject. For example, a chunk of my app looks like this:

Module:

@Module public class PdfFactoryModule { @Provides @Singleton PdfFactory providePdfFactory() { return PdfFactory.getPdfFactory(); } } 

Component:

@Singleton @Component(modules = PdfFactoryModule.class) public interface CorePdfComponent { void inject(PagerFragment pagerFragment); } 

Application:

public class CorePdfApplication extends Application { @NonNull private CorePdfComponent component; @Override public void onCreate() { super.onCreate(); component = DaggerCorePdfComponent.builder().build(); } @NonNull public CorePdfComponent getComponent() { return component; } } 

PagerFragment:

public class PagerFragment extends Fragment { @Inject PdfFactory pdfFactory; @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); //Dagger 2 ((CorePdfApplication) getActivity().getApplication()).getComponent().inject(this); } 

(Note that these are only snippets of my whole code, I'm showing only the essentials for this particular dependency to keep it clear.)

I was trying to do a test like this:

Fake Module:

@Module public class FakePdfFactoryModule extends PdfFactoryModule { @Override PdfFactory providePdfFactory() { return Mockito.mock(PdfFactory.class); } } 

Fake Component:

@Singleton @Component(modules = FakePdfFactoryModule.class) public interface FakeCorePdfComponent extends CorePdfComponent { void inject(PagerFragmentTest pagerFragmentTest); } 

Fake Application:

public class FakeCorePdfApplication extends CorePdfApplication { @NonNull private FakeCorePdfComponent component; @Override public void onCreate() { super.onCreate(); component = DaggerFakeCorePdfComponent.builder().build(); } @NonNull public FakeCorePdfComponent getComponent() { return component; } } 

Test:

@RunWith(RobolectricTestRunner.class) @Config(constants = BuildConfig.class, sdk = 21, application = FakeCorePdfApplication.class) public class PagerFragmentTest { PagerFragment pagerFragment; @Before public void setup() { pagerFragment = new PagerFragment(); startVisibleFragment(pagerFragment); } @Test public void exists() throws Exception { assertNotNull(pagerFragment); } 

But the DaggerFakeCorePdfComponent doesn't generate. I may have messed up big time because I never tested with dependency injection. What am I doing wrong?