rustledger-lsp

Language Server Protocol (LSP) implementation for Beancount files.

Features

Diagnostics: Real-time syntax and validation errors
Completion: Accounts, currencies, payees, tags, links
Hover: Account balances, metadata, directive info
Go to Definition: Jump to account/commodity declarations
Find References: Find all uses of an account or commodity
Document Symbols: Outline view of accounts and directives
Workspace Symbols: Search across all files
Rename: Rename accounts across files
Code Actions: Quick fixes for common issues
Formatting: Format documents and selections
Folding: Collapse transactions and sections
Semantic Highlighting: Rich syntax coloring
Inlay Hints: Inline balance and cost annotations
Code Lens: Inline account statistics

Installation

The LSP server is included with rustledger:

# Via package manager (includes rledger-lsp)
brew install rustledger
yay -S rustledger-bin

# Via Cargo (LSP is a separate crate)
cargo install rustledger-lsp

# Or build from source
cargo build --release -p rustledger-lsp

Usage

# Start the LSP server (communicates via stdio)
rledger-lsp

# Check version
rledger-lsp --version

Editor Setup

VS Code

Install two extensions:

Lencerf.beancount for syntax highlighting
Generic LSP Client (v2) to connect to rledger-lsp

code --install-extension Lencerf.beancount
code --install-extension zsol.vscode-glspc

Add to .vscode/settings.json:

{
  "glspc.server.command": "rledger-lsp",
  "glspc.server.commandArguments": [],
  "glspc.server.languageId": ["beancount"]
}

Neovim (nvim-lspconfig)

-- Add to your Neovim config
local lspconfig = require('lspconfig')
local configs = require('lspconfig.configs')

-- Register rledger-lsp if not already defined
if not configs.rledger then
  configs.rledger = {
    default_config = {
      cmd = { 'rledger-lsp' },
      filetypes = { 'beancount' },
      root_dir = lspconfig.util.root_pattern('.git', '*.beancount'),
      settings = {},
    },
  }
end

lspconfig.rledger.setup {}

Helix

Add to ~/.config/helix/languages.toml:

[[language]]
name = "beancount"
language-servers = ["rledger-lsp"]

[language-server.rledger-lsp]
command = "rledger-lsp"

Zed

Add to ~/.config/zed/settings.json:

{
  "lsp": {
    "rledger-lsp": {
      "binary": {
        "path": "rledger-lsp"
      }
    }
  },
  "languages": {
    "Beancount": {
      "language_servers": ["rledger-lsp"]
    }
  }
}

Emacs (lsp-mode)

(use-package lsp-mode
  :hook (beancount-mode . lsp)
  :config
  (lsp-register-client
   (make-lsp-client
    :new-connection (lsp-stdio-connection '("rledger-lsp"))
    :major-modes '(beancount-mode)
    :server-id 'rledger-lsp)))

Emacs (eglot)

(add-to-list 'eglot-server-programs
             '(beancount-mode . ("rledger-lsp")))

Sublime Text (LSP)

Install the LSP package, then add to LSP settings:

{
  "clients": {
    "rledger": {
      "enabled": true,
      "command": ["rledger-lsp"],
      "selector": "source.beancount"
    }
  }
}

Troubleshooting

LSP not starting?

Ensure rledger-lsp is in your PATH: which rledger-lsp
Check logs: most editors have an LSP log panel
Try running manually: echo '{"jsonrpc":"2.0","method":"initialize","id":1,"params":{}}' | rledger-lsp

No completions?

Ensure the file has .beancount extension
Check that your editor's LSP client is configured for the beancount filetype

Architecture

Based on rust-analyzer patterns:

Main loop handles LSP messages via stdio
Notifications processed synchronously
Requests dispatched to threadpool
Revision-based cancellation for stale requests
Virtual file system for unsaved buffers

License

GPL-3.0-only

rustledger-lsp 0.11.0