Kern VS Code Extension

This extension wires VS Code to kern-lsp and provides a baseline editing experience for .rn source files.

Features

• Kern language registration for .rn
• stdio LSP connection to kern-lsp
• diagnostics, hover, completion, rename, semantic tokens, and code actions
• a lightweight TextMate grammar and language configuration for editor basics
• a Kern: Restart Language Server command
• a Kern: Show Language Server Output command
• starter snippets for common Kern declarations

Development

Install the JavaScript dependencies and compile the extension:

cd editors/vscode
npm install
npm run compile

Open the repository in VS Code and press F5 from the editors/vscode directory to launch an Extension Development Host.

The extension also includes checked-in VS Code launch/tasks files under editors/vscode/.vscode/ so repository-local extension debugging works without extra manual setup.

For manual syntax-highlighting review, open:

editors/vscode/testdata/highlighting-showcase.rn

Language Server Resolution

The extension resolves the language server in this order:

1. kern.server.path
2. target/debug/kern-lsp or target/release/kern-lsp inside the current workspace
3. kern-lsp on PATH

This makes local repository development convenient while still working with a separately installed toolchain.

Settings

• kern.server.path: explicit path to the kern-lsp executable
• kern.server.args: additional command-line arguments passed to kern-lsp

Status

The extension is intentionally early and is currently aimed at preview use for the 0.6.4 release while the broader 0.6.5 LSP maturity milestone is still being hardened.