pr-type-label.yaml

name: PR Type Label

# Applies a label matching the conventional-commit type in the PR title
# (feat, fix, docs, ...) so auto-generated release notes (.github/release.yml)
# can group PRs by category. Titles are validated by pr-title-lint.yaml.

on:
  pull_request_target:
    types:
      - opened
      - edited
      - reopened
      - synchronize

permissions:
  contents: read
  pull-requests: write
  issues: write

concurrency:
  group: pr-type-label-${{ github.event.pull_request.number }}
  cancel-in-progress: false

jobs:
  label:
    runs-on: ubuntu-latest
    timeout-minutes: 5
    steps:
      # No checkout: this job never runs PR code, it only reads the title.
      - name: Apply type label from PR title
        env:
          GH_TOKEN: ${{ github.token }}
          PR_NUMBER: ${{ github.event.pull_request.number }}
          PR_AUTHOR: ${{ github.event.pull_request.user.login }}
          REPO: ${{ github.repository }}
        run: |
          set -euo pipefail

          # Dependabot PRs are already labeled `dependencies` by Dependabot and
          # are categorized by that label alone in release notes.
          if [[ "$PR_AUTHOR" == "dependabot[bot]" ]]; then
            echo "Dependabot PR, skipping type label"
            exit 0
          fi

          # Read current state so delayed runs and reruns use the latest title and labels.
          pr=$(gh pr view "$PR_NUMBER" --repo "$REPO" --json title,labels)
          PR_TITLE=$(jq -r '.title' <<< "$pr")
          PR_LABELS=$(jq -c '[.labels[].name]' <<< "$pr")

          types="feat fix docs test refactor build chore ci perf security revert release style"

          type=""
          re='^([a-z]+)(\([a-z0-9._/-]+\))?!?: '
          if [[ "$PR_TITLE" =~ $re ]]; then
            candidate="${BASH_REMATCH[1]}"
            for t in $types; do
              if [[ "$candidate" == "$t" ]]; then
                type="$t"
                break
              fi
            done
          fi

          # Remove stale type labels when the title type changes or becomes
          # non-conventional (for example, when changed to a [WIP] title).
          for t in $types; do
            if [[ "$t" != "$type" ]] && jq -e --arg label "$t" 'index($label) != null' <<< "$PR_LABELS" >/dev/null; then
              gh pr edit "$PR_NUMBER" --repo "$REPO" --remove-label "$t"
            fi
          done

          if [[ -z "$type" ]]; then
            echo "No conventional type found; stale type labels removed: $PR_TITLE"
            exit 0
          fi

          # Ensure the label exists (no-op if it already does).
          gh label create "$type" \
            --repo "$REPO" \
            --description "PRs of type $type (auto-applied from title)" \
            --color "ededed" 2>/dev/null || true

          if ! jq -e --arg label "$type" 'index($label) != null' <<< "$PR_LABELS" >/dev/null; then
            gh pr edit "$PR_NUMBER" --repo "$REPO" --add-label "$type"
            echo "Applied label: $type"
          else
            echo "Label already present: $type"
          fi