fluffos-vscode — LPC (FluffOS) extension for VS Code

The LPC (FluffOS) VS Code extension: syntax highlighting, structural diagnostics as you type, Format Document / format-on-save, and optional real compiler errors via the FluffOS lpcc front-end.

The extension source lives here (extension/). Its language engine is an output of the fluffos driver repository, pinned via the fluffos/ git submodule: the grammar-driven tokenizer/formatter/linter and grammar contract (fluffos/tools/lpc-syntax/) are synced into extension/lib/ and extension/syntaxes/ at build time. The engine is generated from the compiler's own grammar, so the extension can never drift from what the driver actually accepts — and every release is traceable to an exact driver commit.

The extension also ships a Compiler Explorer (LPC: Open Compiler Explorer, or the circuit-board icon on any LPC editor): per-file Source / Tokens / AST / Bytecode / Preprocessed views of the real compile pipeline, with breadcrumbs, an AST graph, and click-through links back to the source. Source and Tokens work out of the box (bundled grammar tokenizer); the compiler stages need the lpc.lpcc.path + lpc.lpcc.configFile settings. With an lpcc that supports --json (fluffos ≥ 2026-07), tokens carry grammar names and every AST node is click-to-source; older lpcc falls back to parsing the human-readable dumps.

Planned next: build lpcc to WebAssembly upstream (it is native-only in the fluffos CMake today) and ship it as a consumed artifact here, so the Explorer's compiler stages and save-time diagnostics work with zero native setup — and keep the extension web-compatible.

Install

• Download the .vsix from the latest release and run:

  code --install-extension fluffos-lpc-<version>.vsix

• Or, once published, install LPC (FluffOS) from the VS Code Marketplace / Open VSX.

Features and settings are documented in extension/README.md (the packaged extension README).

Repository layout

Path	What
extension/	The extension source: extension.js, manifest, language configuration, packaged README.
extension/lib/, extension/syntaxes/	Generated, gitignored — synced from the submodule by the build; never edit, never commit.
fluffos/	Git submodule — the pinned fluffos commit the language engine is taken from.
scripts/build.mjs	Syncs the engine from the pin, stages extension/ into out/extension/, patches version + fluffos.commit metadata, packages the .vsix with @vscode/vsce.
scripts/test.mjs	Extension-local checks (manifest, extension.js wiring, synced-engine smoke test).
.github/workflows/ci.yml	Push/PR: upstream tooling tests + extension tests + packaging dry run; uploads the .vsix artifact.
.github/workflows/release.yml	Tag vX.Y.Z or manual dispatch: GitHub Release with the .vsix; optional Marketplace / Open VSX publish.
.github/workflows/bump-fluffos.yml	Weekly + manual: bumps the submodule to latest fluffos master, tests, opens a PR.

Build & develop locally

Requires Node ≥ 18 and git; no npm install (@vscode/vsce is fetched by npx at package time).

git clone --recurse-submodules https://github.com/fluffos/fluffos-vscode
cd fluffos-vscode
node scripts/test.mjs      # sync + all local checks (offline-friendly)
node scripts/build.mjs     # out/fluffos-lpc-<version>.vsix

For extension development: run node scripts/build.mjs --no-package once (populates extension/lib/ and extension/syntaxes/), then open extension/ in VS Code and press F5 (Run Extension).

Cutting a release

1. Make sure main is green and the submodule points where you want it (merge the latest "Bump fluffos pin" PR if one is open).

2. Either push a tag:

   git tag v0.1.0 && git push origin v0.1.0

   or run the Release workflow from the Actions tab with the version as input (it creates the tag for you).

The workflow re-runs the tests, packages fluffos-lpc-<version>.vsix, and creates a GitHub Release with the pinned fluffos commit noted. If the VSCE_PAT (VS Code Marketplace) and/or OVSX_PAT (Open VSX) repository secrets are configured, it also publishes there; otherwise those steps are skipped.

Updating the fluffos pin

The Bump fluffos pin workflow does this weekly (and on demand from the Actions tab). By hand:

git -C fluffos fetch origin master
git -C fluffos checkout origin/master
node scripts/test.mjs && node scripts/build.mjs
git add fluffos && git commit -m "Bump fluffos submodule to $(git -C fluffos rev-parse --short HEAD)"

What to change where

• Extension behavior (activation, diagnostics plumbing, settings, manifest, lpcc integration): here, under extension/.
• The language engine (tokenizer, formatter, linter, grammar contract, TextMate grammar): upstream in fluffos tools/lpc-syntax/ — it is generated from the compiler's grammar and tested there. Change it there, then bump the pin here. Never edit extension/lib/ or extension/syntaxes/; the build overwrites them.

Licensing

This repository is licensed under GPL-3.0. The extension package declares MIT (extension/package.json), and the packaged .vsix ships the MIT license text accordingly.