stack/.github/workflows/reviewers-assignees.yml

name: Sync Reviewers and Assignees

on:
  pull_request_target:
    types: [review_requested]
  pull_request_review:
    types: [submitted]

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

jobs:
  sync:
    runs-on: ubuntu-latest
    steps:
      - name: Add reviewer as assignee
        if: ${{ github.event_name == 'pull_request' && github.event.action == 'review_requested' }}
        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
        with:
          script: |
            const pr = context.payload.pull_request;
            const reviewer = context.payload.requested_reviewer;
            if (!reviewer || !reviewer.login) {
              core.info('No individual reviewer in payload (team review or missing). Skipping.');
              return;
            }
            await github.rest.issues.addAssignees({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: pr.number,
              assignees: [reviewer.login],
            });
            core.info(`Assigned ${reviewer.login} to PR #${pr.number}`);            

      - name: Remove reviewer from assignees on review submission
        if: ${{ github.event_name == 'pull_request_review' && github.event.action == 'submitted' }}
        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
        with:
          script: |
            const pr = context.payload.pull_request;
            const reviewer = context.payload.review?.user;
            const state = context.payload.review?.state?.toLowerCase();
            const author = pr.user;
            if (!reviewer || !reviewer.login) {
              core.info('No reviewer user found in payload. Skipping.');
              return;
            }
            if (!state) {
              core.info('No review state provided. Skipping.');
              return;
            }
            if (!['approved', 'changes_requested'].includes(state)) {
              core.info(`Review state is '${state}' (likely a comment). Not removing assignee.`);
              return;
            }
            if (author && reviewer.login === author.login) {
              core.info('Reviewer is the PR author. Not removing assignee.');
              return;
            }
            await github.rest.issues.removeAssignees({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: pr.number,
              assignees: [reviewer.login],
            });
            core.info(`Removed ${reviewer.login} from assignees on PR #${pr.number}`);

            if (author?.login) {
              await github.rest.issues.addAssignees({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: pr.number,
                assignees: [author.login],
              });
              core.info(`Re-assigned PR author ${author.login} to PR #${pr.number}`);
            } else {
              core.info('No PR author found to re-assign.');
            }