(Possible Bug) Pop dialog doesn't work in Flutter Test ?

[tperin-cap]

TL;DR
Hello all! I'm writing tests for a service that shows pop-up in my app and when I'm trying to close the pop-up dialog with Autorouter.pop, it's not working, whereas Navigator.of(context).pop works just fine.

Context
My autorouter class is registered in a GetIt instance and called AppRouter. So when I want to navigate, all I go is "getIt().push(...)" or ".pop(...)". It works just fine.

@AutoRouterConfig(replaceInRouteName: 'Screen|View,Route')
class AppRouter extends RootStackRouter {
  @override
  List<AutoRoute> get routes => [
    AutoRoute(page: HomePageRoute.page, initial: true),
    AutoRoute(page: Page1.page),
    AutoRoute(page: Page2.page),
    AutoRoute(page: Page3.page),
  ];
}

My pop-up service looks like this

class PopUpService {
  bool get isPopUpVisible => _isPopUpVisible;

  bool _isPopUpVisible = false;

  void hidePopUp({dynamic returnValue}) {
    if (!isPopUpVisible) return;

    locator<AppRouter>().pop(returnValue);
    _isPopUpVisible = false;
  }

  Future<dynamic> showPopUp() {
    if(_isPopUpVisible) {//TODO}
    _isPopUpVisible = true;
    return showDialog(
         ...,
         child: ElevatedButton(
           onPressed: () => hidePopUp(),
           child: Text("Close pop up"),
         ),
     );
  }
}

Issue
When I want to show a dialog, I'll call getIt<PopUpService>().showPopUp() which turns isPopUpVisible to true, then the user clicks the button which calls locator<AppRouter>().pop() and closes the dialog.

This works just fine in the app.
Now I'm running this test:
Pump a Widget with a button to call show dialog --> pump --> press the button --> pump --> verify the Dialog widget is found --> press close --> pump --> verify the Dialog widget is gone

If I have onPressed: () => Navigator.of(context).pop(), this works.
If I have it as it is in the code snippet above, this doesn't work.

Am I missing something or is it a bug ?