Rollup merge of #143056 - fmease:mv-ace-test-out-of-gci-dir, r=BoxyUwU

Move an ACE test out of the GCI directory

In https://github.com/rust-lang/rust/pull/122988, a test pertaining to `associated_const_equality` was placed into the directory meant for `generic_const_items`. Let's move it where it belongs.

While at it, I took the time to further minimize the test and to add a description. You can use 1.67.1 (as reported in rust-lang/rust#108220) to verify that I didn't butcher it. For additional context, the issue was likely fixed in rust-lang/rust#112718 (but I'm also cc'ing rust-lang/rust#140467 which further fixed things up and has more context).

I only performed quick and dirty git/GitHub archeology, so I don't have the full picture here. For one, I'm not even sure if this regression test is worth it.

Anyway, I just want it gone from the GCI dir :)

tests/ui/associated-consts/assoc-const-eq-const_evaluatable_unchecked.rs

@@ -0,0 +1,17 @@
+// The impl of lint `const_evaluatable_unchecked` used to wrongly assume and `assert!` that
+// successfully evaluating a type-system constant that has non-region args had to be an anon const.
+// In the case below however we have a type-system assoc const (here: `<() as TraitA<T>>::K`).
+//
+// issue: <https://github.com/rust-lang/rust/issues/108220>
+//@ check-pass
+#![feature(associated_const_equality)]
+
+pub trait TraitA<T> { const K: u8 = 0; }
+pub trait TraitB<T> {}
+
+impl<T> TraitA<T> for () {}
+impl<T> TraitB<T> for () where (): TraitA<T, K = 0> {}
+
+fn check<T>() where (): TraitB<T> {}
+
+fn main() {}

tests/ui/generic-const-items/assoc-const-AnonConst-ice-108220.rs

@@ -1,35 +0,0 @@
-// ICE assertion failed: matches!(self.def_kind(ct.def.did), DefKind :: AnonConst)
-// issue: rust-lang/rust#108220
-//@ check-pass
-
-#![feature(associated_const_equality)]
-#![allow(unused)]
-
-use std::marker::PhantomData;
-
-pub struct NoPin;
-
-pub trait SetAlternate<const A: u8> {}
-
-impl SetAlternate<0> for NoPin {}
-
-pub trait PinA<PER> {
-    const A: u8;
-}
-
-impl<PER> PinA<PER> for NoPin {
-    const A: u8 = 0;
-}
-
-pub trait Pins<USART> {}
-
-impl<USART, T, const TA: u8> Pins<USART> for T where
-    T: PinA<USART, A = { TA }> + SetAlternate<TA>
-{
-}
-
-struct Serial<USART>(PhantomData<USART>);
-
-impl<USART> Serial<USART> where NoPin: Pins<USART> {}
-
-fn main() {}