label-sync.yml

name: Label PRs

on:
  pull_request:
    types: [opened, synchronize]

permissions: {}

jobs:
  label:
    name: Auto-label by path
    runs-on: ubuntu-latest
    # Fork PRs get a read-only token, so labeling cannot succeed there.
    if: github.event.pull_request.head.repo.full_name == github.repository
    permissions:
      contents: read
      pull-requests: write
    steps:
      - name: Apply labels by changed path
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GH_REPO: ${{ github.repository }}
          PR_NUMBER: ${{ github.event.pull_request.number }}
        run: |
          FILES="$(gh pr diff "$PR_NUMBER" --name-only)"
          LABELS=""

          if echo "$FILES" | grep -q "^standards/"; then
            LABELS="$LABELS standards"
          fi

          if echo "$FILES" | grep -q "^scaffold/"; then
            LABELS="$LABELS scaffold"
          fi

          if echo "$FILES" | grep -q "^docs/"; then
            LABELS="$LABELS documentation"
          fi

          if echo "$FILES" | grep -q "^registry.json"; then
            LABELS="$LABELS registry"
          fi

          if echo "$FILES" | grep -q "^\.github/"; then
            LABELS="$LABELS ci"
          fi

          if [ -z "$LABELS" ]; then
            echo "No labels to apply"
            exit 0
          fi

          EXISTING="$(gh label list --limit 200 --json name --jq '.[].name')"
          for label in $LABELS; do
            # Create only when missing, so existing label colors are kept.
            if ! printf '%s\n' "$EXISTING" | grep -qx "$label"; then
              gh label create "$label" --color "ededed" || true
            fi
            gh pr edit "$PR_NUMBER" --add-label "$label"
          done
          echo "Applied labels:$LABELS"