pr-title-lint.yml

name: PR Title Lint

on:
  pull_request_target: # This workflow has permissions on the repo, do NOT run code from PRs in this workflow. See https://securitylab.github.com/research/github-actions-preventing-pwn-requests/ # zizmor: ignore[dangerous-triggers] we know what we are doing here
    types: [opened, edited, reopened, synchronize]

permissions:
  contents: read
  pull-requests: read

jobs:
  lint-pr-title:
    name: Lint PR title
    runs-on: ubuntu-latest
    steps:
      - name: Validate title
        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
        with:
          script: |
            const title = context.payload.pull_request.title || "";

            const bracketedAllowed = [
              /^\[BREAKING\]/,
              /^\[BUGFIX\]/,
              /^\[BUGFIX beta\]/,
              /^\[BUGFIX lts\]/,
              /^\[BUGFIX release\]/,
              /^\[BUGFIX lts-\d+-\d+\]/,
              /^\[DOC\]/,
              /^\[DOC beta\]/,
              /^\[DOC release\]/,
              /^\[SECURITY\]/,
              /^\[SECURITY CVE-\d+\]/,
              /^\[FEATURE [^\]]+\]/,
              /^\[CLEANUP\]/
            ];

            const bracketMatch = title.match(/^\[[^\]]+\]/);
            if (bracketMatch) {
              const ok = bracketedAllowed.some((re) => re.test(title));
              if (!ok) {
                core.setFailed(
                  `Invalid bracket tag in PR title: "${bracketMatch[0]}". ` +
                  "Allowed: [BREAKING], [BUGFIX], [BUGFIX beta], [BUGFIX lts], [BUGFIX release], " +
                  "[BUGFIX lts-6-8], [DOC], [DOC beta], [DOC release], [SECURITY], [SECURITY CVE-1234], " +
                  "[FEATURE any-feature-flag-name], [CLEANUP]."
                );
              }
              return;
            }

            const conventionalMatch = title.match(/^([a-z]+)(\([^)]+\))?:\s/);
            if (conventionalMatch) {
              core.setFailed(
                "Conventional or semantic prefixes are not allowed in PR titles. (ex: `fix:` or `feat:`) " +
                "Use an allowed bracket tag or no prefix."
              );
            }

  comment-if-fix:
    name: Comment on PR if title includes "Fix" without a bracket tag
    runs-on: ubuntu-latest
    permissions:
      issues: write
    steps:
      - name: Validate title
        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
        with:
          script: |
            const title = context.payload.pull_request.title || "";
            const prNumber = context.payload.pull_request.number;
            const owner = context.repo.owner;
            const repo = context.repo.repo;

            const marker = "<!-- pr-title-lint-fix-suggestion -->";
            const bracketMatch = title.match(/^\[[^\]]+\]/);
            if (!bracketMatch && /\bFix\b/i.test(title)) {
              const { data: comments } = await github.rest.issues.listComments({
                owner,
                repo,
                issue_number: prNumber
              });

              const alreadyCommented = comments.some(
                (comment) =>
                  comment.user?.type === "Bot" &&
                  typeof comment.body === "string" &&
                  comment.body.includes(marker)
              );

              if (!alreadyCommented) {
                await github.rest.issues.createComment({
                  owner,
                  repo,
                  issue_number: prNumber,
                  body:
                    `${marker}\n` +
                    "This PR title includes \"Fix\". Should it include `[BUGFIX]` at the start? See https://github.com/emberjs/ember.js/blob/main/CONTRIBUTING.md#commit-tagging"
                });
              }
            }