feat: allow formatter to format stdin

[xJonathanLEI]

Feature Request

Describe the Feature Request

Currently the formatter only takes file paths as input. Would be nice if it can take stdin as input when the argument is -. This is useful in editors, which usually interface with formatters via stdin/stdout.

Describe Preferred Solution

Read from stdin when the supplied argument is -.

Describe Alternatives

N/A

Related Code

N/A

Additional Context

N/A

If the feature request is approved, would you be willing to submit a PR? (Help can be provided if you need assistance submitting a PR)

• [x] Yes
• [ ] No

[xJonathanLEI]

I have a branch that works quite well. It's interfacing with Helix perfectly (and REALLY fast compared to the old cairo-format from cairo-lang).

It needs some cleanup but I can polish it up and submit the PR once this issue is approved.

[spapinistarkware]

Sounds legit, would love to get a PR. And also tips on how to integrate with Helix :)

[xJonathanLEI]

Sure will submit the PR soon. For Helix integration, I simply added this to my languages.toml (located at ~/.config/helix/languages.toml):

[[language]]
name = "cairo"
formatter = { command = "formatter_cli" , args = ["-"] }

It really is :zap: blazing :zap: fast :zap: lol.

This works because Helix simply sends the entire buffer to the formatter command via stdin.

[spapinistarkware]

Can it integrate with langserver?

[xJonathanLEI]

Oh Helix has native support for LSP and it supports formatting through the LSP as long as the server supports it.

Though somehow I haven't successfully used the Cairo LSP for really anything at all, but I'll investigate on that front a bit and submit a separate issue.

[xJonathanLEI]

I have a branch ready now, but I'm wondering how we should deal with the formatter CI issue. Should I just add an .cairofmtignore to crates/parser/test_data/cairo_files/ to just exclude everything there?

[xJonathanLEI]

Btw the formatter code was pretty tightly coupled with the file system, so I had to do some refactoring here and there or else I would have a lot of code duplications. I ended up almost rewriting the whole cli.rs file... I hope you don't mind.

[xJonathanLEI]

Update on the LSP issue: I'm trying the language server again with the current main head and it seems to work for me this time. Hover and going to definition work just fine. Not sure what I got wrong last time so I guess we're good.

However, formatting through the LSP doesn't seem to work. From Helix logs I can clearly see the response for the textDocument/formatting request, but the editor doesn't seem to do anything about it. Helix works fine with formatting through LSP for other languages like rust-analyzer, so I doubt there's something wrong with the Cairo LSP implementation. Will dig deeper and submit the issue.

Note that making formatting work through LSP doesn't supersede this issue.

[xJonathanLEI]

For the follow-up on the LSP formatting issue: #1141

[spapinistarkware]

Do you get semantic higlighting?

[xJonathanLEI]

@spapinistarkware Helix seems to rely solely on treesitter for syntax highlighting so I can't tell. I haven't tried using the Cairo LSP with neovim tho.