Robolectric test using custom shadow class

AdIdTest.java

@RunWith(RobolectricTestRunner.class)
@Config(sdk = {VERSION_CODES.P}, shadows = {ShadowAdvertisingIdClient.class})
public class AdIdTest {

    private Context context = ApplicationProvider.getApplicationContext();

    @Test
    public void test_when_context_is_not_null_then_get_advertising_id() {

        AdvertisingIdClient.Info adId = new AdIdHelper(context).getAdvertisingID(context);
        assertThat(adId).isNotNull();
        assertThat(adId.getId()).isEqualTo("dsf0e47-90s4-4d5d-4949-6d0ba49dc350");

    }

}

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@Implements(AdvertisingIdClient.class)
public class ShadowAdvertisingIdClient {

    public static Info getAdvertisingIdInfo(Context var0) throws IOException, IllegalStateException,
            GooglePlayServicesNotAvailableException, GooglePlayServicesRepairableException {

        return new Info("dsf0e47-90s4-4d5d-4949-6d0ba49dc350", false);
    }

}