auto-close-issues.yml

name: Auto Close Issues

on:
  pull_request:
    types: [closed]

permissions:
  issues: write
  pull-requests: read

jobs:
  close-issues:
    if: github.event.pull_request.merged == true
    runs-on: ubuntu-latest
    steps:
      - name: Close linked issues
        uses: actions/github-script@v7
        with:
          script: |
            const prBody = context.payload.pull_request.body || '';
            const prTitle = context.payload.pull_request.title || '';

            // Extract issue numbers from PR body and title
            // Matches patterns like: "Closes #37", "Fixes #42", "Resolves #100"
            const issuePattern = /(?:close[sd]?|fix(?:e[sd])?|resolve[sd]?)\s+#(\d+)/gi;
            const issues = new Set();

            let match;
            while ((match = issuePattern.exec(prBody)) !== null) {
              issues.add(match[1]);
            }
            while ((match = issuePattern.exec(prTitle)) !== null) {
              issues.add(match[1]);
            }

            // Close each referenced issue
            for (const issueNumber of issues) {
              try {
                await github.rest.issues.update({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: parseInt(issueNumber),
                  state: 'closed'
                });

                await github.rest.issues.createComment({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: parseInt(issueNumber),
                  body: `Automatically closed by merged PR #${context.payload.pull_request.number}`
                });

                core.info(`Closed issue #${issueNumber}`);
              } catch (error) {
                core.warning(`Failed to close issue #${issueNumber}: ${error.message}`);
              }
            }

            if (issues.size === 0) {
              core.info('No issues to close found in PR body or title');
            } else {
              core.info(`Closed ${issues.size} issue(s)`);
            }