Possible Bug: BaseModel.equals not working with null property

[ghost]

I got the following case happening in my application. Whenever the currentTrip property of my state mutates, i get the desired results, my widget is rebuilt to show new information. The way this variable mutates is through the following action:

class FetchTripAction extends ReduxAction<AppState>{
  @override
  FutureOr<AppState> reduce() async {
    Trip trip;

    // -- Fetch current trip from server
    ApiResponse tripResponse = await ApiServices.get( "/api/current-trip" );

    // -- If response contains trip data, parse it
    if( JsonUtils.isJson( tripResponse.data ) ) {
      // -- Parse trip from received data
      trip = Trip.fromJson( tripResponse.data );
    }

    // -- Create new state. Trip CAN be null if employee is not in trip
    return state.copy(
      currentTrip: trip
    );
  }
}

The problem occurs whenever currentTrip mutates into a null value. My widget is not being rebuilt with new information. It seems to only be the case whenever it is null, if a new trip is fetched from the server with different information, my widget is rebuilt as desired. Is there anything that I am overlooking? Thank you dearly in advance !

This is the class that contains current state of my app

class AppState{
  // -- App vars
  final bool working;
  final bool tripInProgress;
  final bool nearVisitLocation;
  final bool websocketConnected;
  final Position currentPosition;
  final List<BranchPhone> branchPhones;

  // -- Entities
  final Trip currentTrip;
  final Employee deliveryEmployee;

  AppState({this.working, this.currentPosition, this.nearVisitLocation, this.tripInProgress,
    this.deliveryEmployee, this.currentTrip, this.websocketConnected, this.branchPhones});

  AppState copy({bool working, Position currentPosition, List<String> savedUsernames,
    bool nearVisitLocation, bool tripInProgress, Employee deliveryEmployee, Trip currentTrip,
    bool websocketConnected, List<BranchPhone> branchPhones,}) => AppState(
        // --
    branchPhones: branchPhones ?? this.branchPhones,
    currentPosition: currentPosition ?? this.currentPosition,
    currentTrip: currentTrip ?? this.currentTrip,
    deliveryEmployee: deliveryEmployee ?? this.deliveryEmployee,
    nearVisitLocation: nearVisitLocation ?? this.nearVisitLocation,
    tripInProgress: tripInProgress ?? this.tripInProgress,
    websocketConnected: websocketConnected ?? this.websocketConnected,
    working: working ?? this.working,
  );

  static Future<AppState> initialState() async{
    // -- Fetch employee if previously logged in and is persisted
    Employee currentEmployee = await Prefs.getFromJson( Prefs.kEmployeeJson , Employee.fromJson );

    // -- Fetch if currently in trip
    bool tripInProgress = StringUtils.parseBoolean( await Prefs.getString( Prefs.kTripInProgress ) );

    // -- Return app state
    return AppState(
      currentPosition: null,
      currentTrip: null,
      branchPhones: [],
      deliveryEmployee: currentEmployee,
      nearVisitLocation: false,
      tripInProgress: tripInProgress,
      websocketConnected: false,
      working: false,
    );
  }
}

The following is the connector widget

class HomePageConnector extends StatelessWidget{
  @override
  Widget build(BuildContext context) {
    return StoreConnector<AppState, HomeViewModel>(
      model: HomeViewModel(),
      onInit: ( Store<AppState> state ) => Hermes.connect(),
      builder: ( BuildContext context, HomeViewModel model ) => HomePage(
        currentTrip: model.currentTrip,
        employee: model.employee,
        branchPhonesCallback: model.branchPhonesCallback,
        logoutCallback: model.logoutCallback,
        startTripCallback: model.startTripCallback,
        websocketConnected: model.websocketConnected,
        working: model.working,
      ),
    );
  }
}

class HomeViewModel extends BaseModel<AppState>{
  // -- Functions and callbacks to pass to view
  Function branchPhonesCallback;
  Function logoutCallback;
  Function startTripCallback;

  // -- Entities and app state to pass to view
  bool working;
  Trip currentTrip;
  Employee employee;
  bool websocketConnected;

  HomeViewModel();
  HomeViewModel.build({
    @required this.branchPhonesCallback,
    @required this.logoutCallback,
    @required this.startTripCallback,
    @required this.currentTrip,
    @required this.employee,
    @required this.websocketConnected,
    @required this.working,
  }) : super(equals: [ currentTrip , employee, websocketConnected, working ]);

  @override
  HomeViewModel fromStore() {
    return HomeViewModel.build(
      branchPhonesCallback: () => dispatch( FetchBranchPhonesAction( employee: store.state.deliveryEmployee ) ),
      logoutCallback: () => dispatch( LogoutAction() ),
      startTripCallback: () => dispatch( StartTripAction( currentTrip: store.state.currentTrip ) ),
      currentTrip: store.state.currentTrip,
      employee: store.state.deliveryEmployee,
      websocketConnected: store.state.websocketConnected,
      working: store.state.working
    );
  }
}

[ghost]

Found the culprit ! Working in late hours of the night really makes one overlook things, whoops ! The issue is the following:

AppState copy({bool working, Position currentPosition, List<String> savedUsernames,
    bool nearVisitLocation, bool tripInProgress, Employee deliveryEmployee, Trip currentTrip,
    bool websocketConnected, List<BranchPhone> branchPhones,}) => AppState(
        // --
    currentTrip: currentTrip ?? this.currentTrip, //<== This is the problem
  );

I cant believe i overlooked this. Closing my issues, thank you regardless !