[FEATURE]:FSharp LSP

[Thorium]

Feature hasn't been suggested before.

• [x] I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

I see that "fsharp" language files are defined in the Opencode configs *.fs, *.fsx and *.fsi but the F# LSP is not installed by default.

LSP for F# is very simple to setup:

1. dotnet tool install fsautocomplete -g
2. Add the following section to the opencode.json:

  "lsp": {
    "fsharp": {
      "command": ["fsautocomplete"],
      "extensions": [".fs", ".fsx", ".fsi"]
    }
  }

...and it works! It would be nice to have this enabled by default in the installation.

[github-actions[bot]]

This issue might be a duplicate of existing issues. Please check:

• #1808: C# language server (csharp-ls) doesn't work - This is a similar language support request within the .NET ecosystem. Understanding how C# LSP support is being addressed may provide insights for F# LSP implementation.

Additionally, you may want to reference other language LSP support requests:

• #3116: Kotlin LSP support - A similar feature request for adding LSP support for another language

Feel free to ignore if your specific case differs from these.

[nalin-singh]

working on this

[nalin-singh]

did start to work, have to do some additional testing

[nalin-singh]

do we also want to add a tree-sitter parser ? [WARN] 'TSWorker:': no parser found for injection language: fsharp

[Thorium]

I think here is the scm: https://raw.githubusercontent.com/ionide/tree-sitter-fsharp/refs/heads/main/queries/highlights.scm

[nalin-singh]

requires a wasm file as well, can't find that

[Thorium]

PR created to put the binaries to repo, but not merged yet. Would bring the wasm to the repo https://github.com/Thorium/tree-sitter-fsharp/raw/8ec2ff6f7c0ce3da6ef9a4e5b73a6b48d90fb3d4/wasm/tree-sitter-fsharp.wasm

[Thorium]

Should we have added the wasm before closing this?

[rekram1-node]

it got auto closed by the merging of pr but yeah prolly good idea there

[rekram1-node]

that's for the syntax highlighting tho

[Thorium]

I'm also looking how to support fantomas as formatter:

https://github.com/sst/opencode/blob/dev/packages/opencode/src/format/formatter.ts

export const fantomas: Info = {
  name: "fantomas",
  command: ["dotnet", "fantomas", "$FILE"],
  extensions: [".fs", ".fsx", ".fsi"],
  async enabled() {
    return Bun.which("dotnet") !== null
  },
}

...but having bun which dotnet is enough to check the availability, it should also somehow check that fantomas is listed in the list when you run dotnet tool list fantomas