rust/tests/ui/const-generics/bad-subst-const-kind.rs

//@ incremental
#![crate_type = "lib"]

trait Q {
    const ASSOC: usize;
}

impl<const N: u64> Q for [u8; N] {
    //~^ ERROR: the constant `N` is not of type `usize`
    const ASSOC: usize = 1;
}

pub fn test() -> [u8; <[u8; 13] as Q>::ASSOC] {
    //~^ ERROR: the constant `13` is not of type `u64`
    todo!()
}
Constrain const vars to error if const types are mismatched 2023-03-19 02:17:44 +00:00			`//@ incremental`
			`#![crate_type = "lib"]`

			`trait Q {`
			`const ASSOC: usize;`
			`}`

			`impl<const N: u64> Q for [u8; N] {`
Add `ConstArgKind::Path` and make `ConstArg` its own HIR node This is a very large commit since a lot needs to be changed in order to make the tests pass. The salient changes are: - `ConstArgKind` gets a new `Path` variant, and all const params are now represented using it. Non-param paths still use `ConstArgKind::Anon` to prevent this change from getting too large, but they will soon use the `Path` variant too. - `ConstArg` gets a distinct `hir_id` field and its own variant in `hir::Node`. This affected many parts of the compiler that expected the parent of an `AnonConst` to be the containing context (e.g., an array repeat expression). They have been changed to check the "grandparent" where necessary. - Some `ast::AnonConst`s now have their `DefId`s created in rustc_ast_lowering rather than `DefCollector`. This is because in some cases they will end up becoming a `ConstArgKind::Path` instead, which has no `DefId`. We have to solve this in a hacky way where we guess whether the `AnonConst` could end up as a path const since we can't know for sure until after name resolution (`N` could refer to a free const or a nullary struct). If it has no chance as being a const param, then we create a `DefId` in `DefCollector` -- otherwise we decide during ast_lowering. This will have to be updated once all path consts use `ConstArgKind::Path`. - We explicitly use `ConstArgHasType` for array lengths, rather than implicitly relying on anon const type feeding -- this is due to the addition of `ConstArgKind::Path`. - Some tests have their outputs changed, but the changes are for the most part minor (including removing duplicate or almost-duplicate errors). One test now ICEs, but it is for an incomplete, unstable feature and is now tracked at #127009. 2024-07-16 19:07:36 -07:00			//~^ ERROR: the constant `N` is not of type `usize`
Constrain const vars to error if const types are mismatched 2023-03-19 02:17:44 +00:00			`const ASSOC: usize = 1;`
			`}`

Partially implement `ConstArgHasType` 2024-05-29 17:06:50 +01:00			`pub fn test() -> [u8; <[u8; 13] as Q>::ASSOC] {`
			//~^ ERROR: the constant `13` is not of type `u64`
			`todo!()`
			`}`