    @Test
    public void test_restart() throws Exception {

        ValueMap.Builder builder = ValueMap.builder();
        RestartableSet set1 = new RestartableSet(builder);

        Subscription subscription = subscribeRestartable(method, subscriber1, scheduler, set1);
        launch(set1);
        subscription.unsubscribe();

        ValueMap state = builder.build();
        clearBackgroundObservables();

        RestartableSet set = new RestartableSet(state, state.toBuilder());
        subscribeRestartable(method, subscriber2, scheduler, set);

        advanceEmission();
        verifyReceived(subscriber2);
        verifyNoLeakedObservables();
    }