const-generics-gat-in-trait-return-type-3.rs

//@ run-pass

// This test unsures that with_opt_const_param returns the
// def_id of the N param in the Bar::Assoc GAT.

trait Bar {
    type Assoc<const N: usize>;
}
trait Foo: Bar {
    fn foo(&self) -> Self::Assoc<3>;
}

impl Bar for () {
    type Assoc<const N: usize> = [(); N];
}

impl Foo for () {
    fn foo(&self) -> Self::Assoc<3> {
        [(); 3]
    }
}

fn main() {
    assert_eq!(().foo(), [(); 3]);
}