type-mismatch incorrectly emitted when a struct/emum with a field named state derives Hash

[LikeLakers2]

rust-analyzer version:
rust-analyzer version: 0.3.1549-standalone (d567091 2023-06-11)

rustc version:
rustc 1.70.0 (90c541806 2023-05-31)

relevant settings:
None that I can think of (though I would be happy to share the settings I've set, if need be!)

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Hi there! I was writing up some code for a custom collection type, when rust-analyzer started emitting a type-mismatch error on me. I found this odd, because rust was itself was still compiling the code just fine - cargo check, cargo build, and cargo clippy all ran without error, even after saving the file with the supposed type-mismatch error.

Upon further investigation, I've found that I'm able to reliably reproduce the issue when all of the following are true:

1. A struct or enum variant has a field named state
2. The struct or enum with that field has a #[derive(Hash)] attribute.

Upon meeting these conditions, rust-analyzer will start incorrectly emitting a type-mismatch error until either 1) the Hash derive is removed, or 2) the state field is renamed. (To be clear, I am unsure if this issue is specific to the Hash derive. It's possible it may affect other derives as well.)

Here is a minimal reproduction of the issue - both a struct and enum are provided.

#[derive(Hash)]
pub struct RaBugStruct {
	state: ()
}

#[derive(Hash)]
pub enum RaBugEnum {
	St {
		state: ()
	}
}

Either of those will produce a type-mismatch error from rust-analyzer, that says expected &mut {unknown}, found &().

P.S. Thanks in advance for making rust-analyzer a little less buggy. :)

[lnicola]

Duplicate of #15039, already fixed 😄.

Nice bug report, though, thanks.

[LikeLakers2]

Ah, my apologies, I missed that when searching for related issues. Glad to hear it's already fixed - now to wait for the rust-analyzer extension to update. :)

And thank you. I do feel it's a little excessive on how much info it gives, but I'd rather give too much information about a bug than not enough. Still, thank you!