State transition chaining

[Indy2222]

Hi,

I have two state enums: AppState and GameState. I need to guarantee that OnEnter(GameState::Y) is executed in the same tick as OnEnter(AppState:X) when NextState<GameState> is changed to GameState::Y in a system run in OnEnter(AppState:X).

I have come up with the following solution:

let app_set = apply_state_transition::<AppState>.into_system_set();
let game_set = apply_state_transition::<GameState>.into_system_set();
app.add_state::<AppState>().add_state::<GameState>().configure_sets((game_set, app_set).chain());

Does that work as I expect? If not, why? What is the canonical solution?

BTW I think that this can be a common pattern (one state depending another / a kind of a hierarchy).

Thank you!