StateScoped entity could cause "Could not despawn entity" warning

[Shatur]

Bevy version

v0.14.2

What you did

I spawned an entity with StateScoped(MyState) component and a children with StateScoped(MySubState) component.

What went wrong

If I exit MyState, both entities will first be despawned by StateScoped(MyState) (due to recursive despawn), and then the child entity will also be attempted to be despawned by StateScoped(MySubState). It causes warning:

WARN bevy_ecs::world: error[B0003]: Could not despawn entity because it doesn't exist in this World. See: https://bevyengine.org/learn/errors/#

I think that the warning shouldn't be emitted in this case.

[benfrankel]

IMO the warning shouldn't be emitted in general, but I won't try to argue for that here. Some other options:

1. Add a try_despawn_recursive command that accepts that the entity may not exist when the command runs, so it doesn't warn.
2. Rebrand StateScoped as enum DespawnOnExit { Single, Descendants, Recursive } so it's more obvious that it does a recursive despawn and you only need to attach it to the root entity.
3. Make no change and consider this a user error, where they shouldn't be putting StateScoped on both parent and child.

[Shatur]

Yeah, I agree that it shouldn't be a warning.

[alice-i-cecile]

Broader issue is #5617.