auto-close-mentioned-issues.yml

name: Auto-close issues mentioned in merged PR

on:
  pull_request_target:
    types: [closed]

permissions:
  issues: write
  pull-requests: read

jobs:
  auto-close-issues:
    runs-on: ubuntu-latest
    if: github.event.pull_request.merged == true

    steps:
      - name: Auto-close referenced issues
        uses: actions/github-script@v7
        with:
          script: |
            const pr = context.payload.pull_request;

            // Combine PR title and body
            const text = `${pr.title}\n${pr.body || ""}`;

            // Match issue references like #12, #45
            const issueNumbers = [...text.matchAll(/#(\d+)/g)]
              .map(match => match[1]);

            if (issueNumbers.length === 0) {
              console.log("No referenced issues found.");
              return;
            }

            for (const issueNumber of issueNumbers) {
              try {
                await github.rest.issues.update({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: issueNumber,
                  state: "closed",
                });

                await github.rest.issues.createComment({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: issueNumber,
                  body: `Closed automatically via merged PR #${pr.number}.`,
                });

                console.log(`Closed issue #${issueNumber}`);
              } catch (error) {
                console.log(
                  `Failed to close issue #${issueNumber}: ${error.message}`
                );
              }
            }