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>
