Use janet-simple grammar for Janet

[sogaiu]

Following up on this comment, this PR is mostly about using the tree-sitter-janet-simple grammar for Janet support along with a syntax highligting query file.

It also adds some bits for janet-format -- a formatter for Janet that comes with the spork library.

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I am aware of 2 grammars [1] for Janet and each took a slightly different approach from the other. The one that's part of this PR is used in nvim-treesitter, difftastic, and there is code to use it from Emacs as well.

Due to historical reasons, this one is named "tree-sitter-janet-simple" (internally janet_simple -- to avoid name collisions) and IIUC that means the value for name in languages.toml needs to be janet-simple (under both [[language]] and [[grammar]]). Or, at least, that's what made it work for me. Please point out if that should be changed and if so how :)

LSP support for Janet is still maturing and although I did get it to work with some degree of success, I didn't feel the time was right yet.

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[1] Here is the other one for reference.

[sogaiu]

Does squashing to a single commit and force-pushing sound ok?

[archseer]

No need to manually squash, we'll squash when merging

[sogaiu]

I don't understand this error:

 Error: "Failed to parse highlights.scm queries for janet: Query error at 5:2. Invalid node type long_str_lit"
Error: Process completed with exit code 1.

I guess the line in question is this one.

I think long_str_lit is a valid node in the grammar.

I don't see any error via :log-open when I view a .janet file -- would an error show up there if there were a problem with highlights.scm?

Any hints as to what I might be missing?

[the-mikedavis]

You need to remove the original [[language]] block for janet. It's overriding grammar to use the clojure one which is causing the queries to fail (since they aren't valid for the clojure grammar)

[the-mikedavis]

You should see the same error printed to the log when opening a janet file. You need to run helix via cargo run to build these changes though - they won't affect any instances of Helix you installed from a package manager or from source

[sogaiu]

Thanks for the hints.

Looks like an extra section got added back here.

I guess my bad for putting the new section elsewhere and removing the old one before the merge (^^;

Sorry about that.

[the-mikedavis]

(The CI failures are unrelated - it's caused by a sourcehut outage)