@nowline/lsp

@nowline/lsp

Language Server Protocol implementation for the Nowline DSL. Built on top of @nowline/core's Langium grammar, validator, and AST. The @nowline/vscode-extension bundles this server; other LSP-capable editors (Neovim, JetBrains, Helix, Emacs, …) can spawn the bundled nowline-lsp binary directly.

What it provides

• Validation — every diagnostic from @nowline/core's validator surfaces in the editor in real time.
• Definition — jump from after:audit-log, owner:sam, depends:[…], on:…, before:…, etc. to the entity that owns the id.
• References — every text-matching usage of an entity id across the open file.
• Rename — rename an entity id and fan the edit out to all references.
• Hover — entity title, status, owner, and link surfaced when the cursor hovers a name node or a reference.
• Document symbols — outline tree mirroring roadmap → swimlane → item (with parallel / group nesting).
• Completion — id completion inside after: / before: / owner: / on: / depends:[] plus value completion for status:. Keyword and property-key completion comes from Langium's default provider.
• Folding — block folding driven by Langium's default provider over the INDENT/DEDENT-based grammar.

The server is single-file scoped in m3 — cross-file references through include are intentionally not resolved by the LSP. Diagnostics and navigation operate on the document the user is editing.

Running the server

The package ships a nowline-lsp binary. Editors connect over stdio:

npx nowline-lsp

Programmatic embedding (e.g. inside a VS Code extension):

import { startNowlineServer } from '@nowline/lsp/server';

startNowlineServer();

For headless / in-memory usage (tests, MCP, …) use createNowlineLspServices with an EmptyFileSystem.