#[derive(SystemParam)] with inner query filter

[Indy2222]

I have a derived system param:

#[derive(SystemParam)]
pub struct SolidObjects<'w, 's> {
    objects: Query<
        'w,
        's,
        (
            Entity,
            &'static GlobalTransform,
            &'static Aabb,
            &'static Handle<Mesh>,
        ),
    >,
    meshes: ResMut<'w, Assets<Mesh>>,
}

impl<'w, 's> SolidObjects<'w, 's> {
    pub fn ray_intersection(&self, ray: &Ray) -> Option<(Entity, RayIntersection)> {}
}

I want to extend this to enable query filtering. Something like this:

#[derive(SystemParam)]
pub struct SolidObjects<'w, 's, F>
where
    F: WorldQuery + Sync + Send + 'static,
    <F as WorldQuery>::Fetch: FilterFetch,
{
    objects: Query<
        'w,
        's,
        (
            Entity,
            &'static GlobalTransform,
            &'static Aabb,
            &'static Handle<Mesh>,
        ),
        F,
    >,
    meshes: ResMut<'w, Assets<Mesh>>,
}

But it won't compile:

error[E0277]: `F` cannot be shared between threads safely
  --> src/collisions.rs:19:10
   |
19 | #[derive(SystemParam)]
   |          ^^^^^^^^^^^ `F` cannot be shared between threads safely
   |
   = note: required because it appears within the type `PhantomData<F>`

Can someone hint me to what I am doing wrong?

[TheRawMeatball]

Moving the bounds on F from where to being directly on the declaration should make this compile. The where filters not being carried properly seems to be a bug.

[TheRawMeatball]

Fix PR'd in #4400

[Indy2222]

Thank your for the quick reaction and FIX PR!

Moving it directly on the declaration won't work in this case:

error[E0658]: associated type bounds are unstable
  --> src/collisions.rs:19:47
   |
19 | pub struct SolidObjects<'w, 's, F: WorldQuery<Fetch: FilterFetch> + Sync + Send + 'static> {
   |                                               ^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #52662 <https://github.com/rust-lang/rust/issues/52662> for more information

[TheRawMeatball]

#[derive(SystemParam)]
pub struct SolidObjects<'w, 's, F: WorldQuery + Sync + Send + 'static>
where
    <F as WorldQuery>::Fetch: FilterFetch,
{
    objects: Query<
        'w,
        's,
        (
            Entity,
            &'static GlobalTransform,
            &'static Aabb,
            &'static Handle<Mesh>,
        ),
        F,
    >,
    meshes: ResMut<'w, Assets<Mesh>>,
}

should work

[Indy2222]

Unfortunately does not. I will temporarily use the version from the PR until the fix gets to upstream.