@rcrsr/rill-lsp

Language Server Protocol server for the rill scripting language

rill-lsp gives any LSP-capable editor live feedback on .rill files. It speaks JSON-RPC over stdio and reuses rill's own parser (@rcrsr/rill) and language service (@rcrsr/rill-language-service), so the editor reports exactly what the runtime would.

Status

Early. The server reports parse errors, outlines, semantic tokens, and formatting. The remaining features in the table below are in progress.

| Capability | LSP method | Status | |---|---|---| | Parse diagnostics | textDocument/publishDiagnostics | Shipped | | Document outline | textDocument/documentSymbol | Shipped | | Semantic highlighting | textDocument/semanticTokens/full | Shipped | | Formatting | textDocument/formatting | Shipped | | Hover | textDocument/hover | Planned | | Go to definition | textDocument/definition | Planned | | Completion | textDocument/completion | Planned | | Static-check diagnostics | textDocument/publishDiagnostics | Planned |

The server advertises only shipped capabilities, so an editor never calls a method it cannot answer.

Install

Requires Node.js 22.16 or later.

npm install -g @rcrsr/rill-lsp

Or run it without installing:

npx @rcrsr/rill-lsp

Editor setup

Every editor spawns the same command: rill-lsp, communicating over stdio.

Neovim (0.11+)

See docs/clients/neovim.md for setup.

Emacs (eglot)

(define-derived-mode rill-mode prog-mode "rill")
(add-to-list 'auto-mode-alist '("\\.rill\\'" . rill-mode))
(add-to-list 'eglot-server-programs '(rill-mode "rill-lsp"))

Programmatic use

The package also exports the server pieces, for hosts that embed the server or test against it.

| Export | Description | |---|---| | startServer(connection) | Wires every rill feature onto an LSP Connection and starts listening. The caller owns the transport. | | SERVER_CAPABILITIES | The ServerCapabilities object returned from initialize. | | computeDiagnostics(text) | Parses text with error recovery and returns LSP Diagnostic[]. Never throws. | | computeSemanticTokens(text, onError?) | Returns the LSP semantic tokens for text. Never throws; reports failures to the optional onError. | | computeDocumentSymbols(text, onError?) | Returns the LSP document outline for text. Never throws; reports failures to the optional onError. | | computeFormattingEdits(text, onError?) | Returns LSP TextEdit[] that format text. Never throws; reports failures to the optional onError. |

import { createConnection, ProposedFeatures } from 'vscode-languageserver/node';
import { startServer } from '@rcrsr/rill-lsp';

startServer(createConnection(ProposedFeatures.all));

Diagnostics

Each diagnostic carries the rill error ID as its code (for example RILL-P007) and links the error reference through codeDescription.href. Recovery parsing reports one diagnostic per broken statement, so an error early in a file does not hide later ones.

Related packages

| Package | Purpose | |---|---| | @rcrsr/rill | Language runtime and parser | | @rcrsr/rill-language-service | Outline, tokens, formatting, scope, hover, completion, static checker | | @rcrsr/rill-cli | rill command-line tools |

License

MIT