pr-stale-check.yml

name: PR Stale Check

on:
  schedule:
    - cron: "0 7 * * *"
  workflow_dispatch:

permissions:
  pull-requests: write
  issues: write
  checks: read
  statuses: read

jobs:
  stale-check:
    runs-on: ubuntu-latest
    steps:
      - name: Label stale PRs
        uses: actions/github-script@v7
        with:
          script: |
            const STALE_LABEL = 'stale';
            const HIGH_LABEL = 'priority: high';
            const HIGH_DAYS = 3;
            const DEFAULT_DAYS = 7;
            const CLOSE_AFTER_STALE_DAYS = 14;
            const now = Date.now();
            const msPerDay = 86400000;

            const prs = await github.rest.pulls.list({
              owner: context.repo.owner,
              repo: context.repo.repo,
              state: 'open',
            });

            for (const pr of prs.data) {
              if (pr.draft) continue;

              const labels = pr.labels.map(l => l.name);
              const isHigh = labels.includes(HIGH_LABEL);

              // Also check linked issue labels
              if (!isHigh) {
                const { data: events } = await github.rest.issues.listEventsForTimeline({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: pr.number,
                  per_page: 100,
                });
                for (const evt of events) {
                  if (evt.event === 'cross-referenced' && evt.source?.issue) {
                    const issue = evt.source.issue;
                    if (issue.labels?.some(l => l.name === HIGH_LABEL)) {
                      labels.push(HIGH_LABEL);
                      break;
                    }
                  }
                }
              }

              const staleDays = labels.includes(HIGH_LABEL) ? HIGH_DAYS : DEFAULT_DAYS;

              // Find the last event requiring author action:
              // either a "changes requested" review or a failing CI check
              const reviews = await github.rest.pulls.listReviews({
                owner: context.repo.owner,
                repo: context.repo.repo,
                pull_number: pr.number,
              });

              let actionNeededSince = null;
              for (const review of reviews.data) {
                if (review.state === 'CHANGES_REQUESTED') {
                  const t = new Date(review.submitted_at).getTime();
                  if (!actionNeededSince || t > actionNeededSince) {
                    actionNeededSince = t;
                  }
                }
              }

              // Check for failing CI on the head commit
              const { data: checkRuns } = await github.rest.checks.listForRef({
                owner: context.repo.owner,
                repo: context.repo.repo,
                ref: pr.head.sha,
              });
              for (const run of checkRuns.check_runs) {
                if (run.conclusion === 'failure' && run.completed_at) {
                  const t = new Date(run.completed_at).getTime();
                  if (!actionNeededSince || t > actionNeededSince) {
                    actionNeededSince = t;
                  }
                }
              }

              if (!actionNeededSince) {
                if (labels.includes(STALE_LABEL)) {
                  await github.rest.issues.removeLabel({
                    owner: context.repo.owner,
                    repo: context.repo.repo,
                    issue_number: pr.number,
                    name: STALE_LABEL,
                  }).catch(() => {});
                }
                continue;
              }

              // Check if the author responded after the last review
              const authorLogin = pr.user.login;
              const comments = await github.rest.issues.listComments({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: pr.number,
              });

              let authorRespondedAfter = false;
              for (const c of comments.data) {
                if (c.user.login === authorLogin && new Date(c.created_at).getTime() > actionNeededSince) {
                  authorRespondedAfter = true;
                  break;
                }
              }

              // Also check if author pushed after the review
              if (!authorRespondedAfter) {
                const commits = await github.rest.pulls.listCommits({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  pull_number: pr.number,
                });
                for (const c of commits.data) {
                  const commitTime = new Date(c.commit.committer.date).getTime();
                  if (c.author?.login === authorLogin && commitTime > actionNeededSince) {
                    authorRespondedAfter = true;
                    break;
                  }
                }
              }

              if (authorRespondedAfter) {
                if (labels.includes(STALE_LABEL)) {
                  await github.rest.issues.removeLabel({
                    owner: context.repo.owner,
                    repo: context.repo.repo,
                    issue_number: pr.number,
                    name: STALE_LABEL,
                  }).catch(() => {});
                  core.info(`PR #${pr.number}: author responded, removed stale label`);
                }
                continue;
              }

              const daysSince = Math.floor((now - actionNeededSince) / msPerDay);
              core.info(`PR #${pr.number}: ${daysSince}d since changes requested (SLA: ${staleDays}d)`);

              if (daysSince >= staleDays && !labels.includes(STALE_LABEL)) {
                await github.rest.issues.addLabels({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: pr.number,
                  labels: [STALE_LABEL],
                });
                await github.rest.issues.createComment({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: pr.number,
                  body: `This PR has had no author follow-up for ${daysSince} days since changes were requested. Marking as **stale**. Please push updates or comment if you're still working on this.\n\nThis PR will be closed automatically if there is no activity within ${CLOSE_AFTER_STALE_DAYS} days.`,
                });
                core.info(`PR #${pr.number}: marked stale (${daysSince}d)`);
              } else if (labels.includes(STALE_LABEL)) {
                // Find when the stale label was added
                const events = await github.rest.issues.listEvents({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: pr.number,
                });
                let staledAt = null;
                for (const evt of events.data) {
                  if (evt.event === 'labeled' && evt.label?.name === STALE_LABEL) {
                    staledAt = new Date(evt.created_at).getTime();
                  }
                }
                if (staledAt) {
                  const staleDaysSince = Math.floor((now - staledAt) / msPerDay);
                  if (staleDaysSince >= CLOSE_AFTER_STALE_DAYS) {
                    await github.rest.issues.createComment({
                      owner: context.repo.owner,
                      repo: context.repo.repo,
                      issue_number: pr.number,
                      body: `Closing this PR after ${CLOSE_AFTER_STALE_DAYS} days with no activity since being marked stale. Feel free to reopen if you'd like to continue working on this.`,
                    });
                    await github.rest.pulls.update({
                      owner: context.repo.owner,
                      repo: context.repo.repo,
                      pull_number: pr.number,
                      state: 'closed',
                    });
                    core.info(`PR #${pr.number}: auto-closed (${staleDaysSince}d stale)`);
                  }
                }
              }
            }