Support path attributes that don't end with .rs

[bvanjoi]

For example:

// main.rs
#[path = "a.suffix"]
mod a;
fn main() {}

// a.suffix
pub const A: i32 = 1;

rustc main.rs can compile successfully, but ra will report errors:

[poliorcetics]

Relevant docs: https://doc.rust-lang.org/reference/items/modules.html?highlight=%23%5Bpath%20%3D#the-path-attribute and wow I didn't know all of the specifications of the #[path] attribute

[poliorcetics]

I think the issue is not that rust-analyzer doesn't understand such paths.

I tried it and got the error but the moment I open the a.suffix file and tell my editor it's a Rust file, the error disappears. I think either Rust-Analyzer or the editor filter out the files sent to RA by extension.

The fix is probably to make R-A request files in path attributes when it doesn't know about them (i.e, they don't match *.rs). I'm very much unsure about how to fix this though.

[poliorcetics]

Yep, it happens here:

rust-analyzer/crates/rust-analyzer/src/main_loop.rs

Lines 173 to 177 in 55d9a53

	lsp_types::DocumentFilter {
	language: None,
	scheme: None,
	pattern: Some("**/*.rs".into()),
	},

[poliorcetics]

Workaround for people ending up here

1. Open the file that R-A fails to detect
2. Tell your editor it's a Rust file

Editors that correctly implement the LSP spec should pick it up and send it to R-A. You'll have to do it each and every time you restart R-A though (quitting and opening the editor will do it for example)