We can't do the easy hack that we did before anymore, where we kept
track of whether any inference variables changed since the last time we
rechecked obligations. Instead, we store the obligations in
canonicalized form; that way we can easily check the inference variables
to see whether they have changed since the goal was canonicalized.
8813: Get some more array lengths! r=lf- a=lf-
This is built on #8799 and thus contains its changes. I'll rebase it onto master when that one gets merged. It adds support for r-a understanding the length of:
* `let a: [u8; 2] = ...`
* `let a = b"aaa"`
* `let a = [0u8; 4]`
I have added support for getting the values of byte strings, which was not previously there. I am least confident in the correctness of this part and it probably needs some more tests, as we currently have only one test that exercised that part (!).
Fixes#2922.
Co-authored-by: Jade <software@lfcode.ca>
Fix#2922: add unknown length as a condition for a type having unknown.
Incorporate reviews:
* Extract some of the const evaluation workings into functions
* Add fixmes on the hacks
* Add tests for impls on specific array lengths (these work!!! 😁)
* Add tests for const generics (indeed we don't support it yet)
Store impls for e.g. &Foo with the ones for Foo instead of the big
"other" bucket. This can improve performance and simplifies the HIR impl
search a bit.
Almost all uses actually only care about ADT substs, so it's better to
be explicit. The methods were a bad abstraction anyway since they
already didn't include the inner types of e.g. `TyKind::Ref` anymore.
7907: Autoderef with visibility r=cynecx a=cynecx
Fixes https://github.com/rust-analyzer/rust-analyzer/issues/7841.
I am not sure about the general approach here. Right now this simply tries to check whether the autoderef candidate is reachable from the current module. ~~However this doesn't exactly work with traits (see the `tests::macros::infer_derive_clone_in_core` test, which fails right now).~~ see comment below
Refs:
- `rustc_typeck` checking fields: 66ec64ccf3/compiler/rustc_typeck/src/check/expr.rs (L1610)
r? @flodiebold
Co-authored-by: cynecx <me@cynecx.net>