srf-lsp

Language Server Protocol implementation for SRF (Simple Record Format), written in Zig.

Provides real-time parse error diagnostics using the SRF library's parser directly.

Features

• Parse error diagnostics on open and edit, using the SRF library's parser directly: missing or duplicate #!srfv1, bad type hints, unparseable values, data after #!eof, and so on.
• All errors from a parse are reported, not just the first.
• Position encoding is negotiated during initialize (utf-8, utf-16 or utf-32), so columns line up even on lines containing multi-byte characters.
• Full-document sync, which matches SRF's single-pass parser.
• stdio transport.

Not implemented: hover, completion, document symbols, formatting, goto definition, semantic tokens, and pull diagnostics (textDocument/diagnostic). Requests for them are answered with MethodNotFound rather than left unanswered, and none of them are advertised as server capabilities.

Setup

mise install

Build & Test

zig build
zig build test

The binary is at zig-out/bin/srf-lsp.

Install

The Neovim config below expects srf-lsp on PATH:

zig build && install -m755 zig-out/bin/srf-lsp ~/.local/bin/srf-lsp

Neovim Integration

Neovim 0.11 or newer. Add to your config:

vim.filetype.add({
  extension = {
    srf = "srf",
  },
})

vim.lsp.config("srf_lsp", {
  cmd = { "srf-lsp" },
  filetypes = { "srf" },
  root_markers = { ".git", "/" }, -- single file server
})

vim.lsp.enable("srf_lsp")

Check it attached with :checkhealth vim.lsp on a .srf buffer. Server logs go to stderr, which Neovim captures in :LspLog.

Combined Setup (with srf-tree-sitter)

For both syntax highlighting and error detection:

vim.filetype.add({
  extension = {
    srf = "srf",
  },
})

-- Diagnostics
vim.lsp.config("srf_lsp", {
  cmd = { "srf-lsp" },
  filetypes = { "srf" },
  root_markers = { ".git", "/" },
})
vim.lsp.enable("srf_lsp")

-- Syntax highlighting
vim.api.nvim_create_autocmd("User", {
  pattern = "TSUpdate",
  callback = function()
    require("nvim-treesitter.parsers").srf = {
      install_info = {
        url = "https://github.com/elerch/srf-tree-sitter",
        branch = "master",
        queries = "queries",
      },
    }
  end,
})

vim.api.nvim_create_autocmd("FileType", {
  pattern = "srf",
  callback = function(args)
    pcall(vim.treesitter.start, args.buf)
  end,
})

Then install the tree-sitter parser (:TSInstall srf no-ops if it is already present, so use :TSUpdate srf to pick up a newer grammar):

:TSUpdate srf