rust/tests/ui/associated-consts/assoc-const-eq-param-in-ty.rs

// Regression test for issue #108271.
// Detect and reject generic params in the type of assoc consts used in an equality bound.
#![feature(associated_const_equality)]

trait Trait<'a, T: 'a, const N: usize> {
    const K: &'a [T; N];
}

fn take0<'r, A: 'r, const Q: usize>(_: impl Trait<'r, A, Q, K = { loop {} }>) {}
//~^ ERROR the type of the associated constant `K` must not depend on generic parameters
//~| NOTE its type must not depend on the lifetime parameter `'r`
//~| NOTE the lifetime parameter `'r` is defined here
//~| NOTE `K` has type `&'r [A; Q]`
//~| ERROR the type of the associated constant `K` must not depend on generic parameters
//~| NOTE its type must not depend on the type parameter `A`
//~| NOTE the type parameter `A` is defined here
//~| NOTE `K` has type `&'r [A; Q]`
//~| ERROR the type of the associated constant `K` must not depend on generic parameters
//~| NOTE its type must not depend on the const parameter `Q`
//~| NOTE the const parameter `Q` is defined here
//~| NOTE `K` has type `&'r [A; Q]`

trait Project {
    const SELF: Self;
}

fn take1(_: impl Project<SELF = {}>) {}
//~^ ERROR the type of the associated constant `SELF` must not depend on `impl Trait`
//~| NOTE its type must not depend on `impl Trait`
//~| NOTE the `impl Trait` is specified here

fn take2<P: Project<SELF = {}>>(_: P) {}
//~^ ERROR the type of the associated constant `SELF` must not depend on generic parameters
//~| NOTE its type must not depend on the type parameter `P`
//~| NOTE the type parameter `P` is defined here
//~| NOTE `SELF` has type `P`

trait Iface<'r> {
    //~^ NOTE the lifetime parameter `'r` is defined here
    //~| NOTE the lifetime parameter `'r` is defined here
    type Assoc<const Q: usize>: Trait<'r, Self, Q, K = { loop {} }>
    //~^ ERROR the type of the associated constant `K` must not depend on generic parameters
    //~| ERROR the type of the associated constant `K` must not depend on generic parameters
    //~| NOTE its type must not depend on the lifetime parameter `'r`
    //~| NOTE `K` has type `&'r [Self; Q]`
    //~| ERROR the type of the associated constant `K` must not depend on `Self`
    //~| NOTE its type must not depend on `Self`
    //~| NOTE `K` has type `&'r [Self; Q]`
    //~| ERROR the type of the associated constant `K` must not depend on generic parameters
    //~| NOTE its type must not depend on the const parameter `Q`
    //~| NOTE the const parameter `Q` is defined here
    //~| NOTE `K` has type `&'r [Self; Q]`
    //~| NOTE its type must not depend on the lifetime parameter `'r`
    //~| NOTE `K` has type `&'r [Self; Q]`
    //~| ERROR the type of the associated constant `K` must not depend on `Self`
    //~| NOTE its type must not depend on `Self`
    //~| NOTE `K` has type `&'r [Self; Q]`
    //~| ERROR the type of the associated constant `K` must not depend on generic parameters
    //~| NOTE its type must not depend on the const parameter `Q`
    //~| NOTE the const parameter `Q` is defined here
    //~| NOTE `K` has type `&'r [Self; Q]`
    //~| NOTE duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
    //~| NOTE duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
    //~| NOTE duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
    where
        Self: Sized + 'r;
}

fn main() {}