action.yaml

name: Get PR Info
outputs:
  pr-info:
    description: String encoded JSON object containing pull-request information
    value: ${{ steps.get-pull-request.outputs.result }}
runs:
  using: composite
  steps:
    - uses: actions/github-script@v7
      id: get-pull-request
      with:
        retries: 3
        script: |
          return (
            await github.rest.pulls.get({
              repo: context.repo.repo,
              owner: context.repo.owner,
              pull_number: (() => {
                switch('${{ github.event_name }}') {
                  case 'pull_request':
                  case 'pull_request_target':
                    return '${{ github.ref }}'.split('/')[2];
                  case 'push':
                    const branch = '${{ github.ref_name }}';
                    if (!branch.match(new RegExp('^pull-request/[0-9]+$'))) {
                      throw new Error(`${branch} does not match PR branch pattern.`);
                    }
                    return branch.split('/')[1];
                }
                throw new Error(`Could not determine pull request number.`);
              })()
            })
          ).data;