build-standalone.yml

name: Build standalone

on:
  push:
    paths:
      - "src/**"
      - "tools/build.lua"
  workflow_dispatch:

permissions:
  contents: write

concurrency:
  group: build-standalone-${{ github.ref }}
  cancel-in-progress: false

jobs:
  build:
    name: Rebuild shale.lua
    runs-on: ubuntu-latest

    steps:
      - name: Check out branch
        uses: actions/checkout@v6
        with:
          fetch-depth: 0
          ref: ${{ github.ref_name }}

      - name: Update to latest branch revision
        run: git pull --ff-only origin "$GITHUB_REF_NAME"

      - name: Install Lua 5.1
        run: |
          sudo apt-get update
          sudo apt-get install --yes lua5.1

      - name: Build standalone file
        run: lua5.1 tools/build.lua

      - name: Commit generated standalone file
        run: |
          if git diff --quiet -- shale.lua; then
            echo "shale.lua is already up to date."
            exit 0
          fi

          git config user.name "github-actions[bot]"
          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
          git add shale.lua
          git commit -m "chore: rebuild standalone shale.lua"
          git push origin "HEAD:${GITHUB_REF_NAME}"