Espresso test with Dagger2 injection

Question

I want to inject my components that are created by dagger in my Espresso tests.

The components should be the same, so, that are no necessity of overriding anything from dagger.

I have the following class:

@RunWith(AndroidJUnit4.class)
public class AccountRepositoryTest {
    @Inject
    AccountRepository repository;

    @Before
    public void setUp() throws Exception {
        new DaggerTestComponent().builder().build().inject(this);
    }
}

Since I can't add AccountRepositoryTest to my main DaggerComponent class, I created another component class in my androidTests folder:

@Singleton
@Component(modules = arrayOf(AppModule::class, DatabaseModule::class, RepositoryModule::class))
interface TestComponent: AppComponent {
     fun inject(accountRepositoryTest: AccountRepositoryTest)
}

But dagger never generates the ComponentClass from TestComponent interface, when I compile the code, I always receive this error:

Error:(26, 7) error: cannot find symbol class DaggerTestComponent

If I comment the line, my code compiles, so I'm sure that it is just this that is preventing dagger from generating the class.

So my question is: how do make dagger generate a component class from an interface defined in androidTests folder?

Answer 1

The solution was to add dagger-compiler to androidTest dependencies.

If you are using kotlin:

kaptAndroidTest "com.google.dagger:dagger-compiler:$daggerVersion"

If you are using java:

androidTestAnnotationProcessor "com.google.dagger:dagger-compiler:$daggerVersion"