name: cancel-on-close
# A closed or merged pull request's queued and running checks free the runners at once.
# pull_request_target so the token can cancel runs of pull requests from forks too;
# it checks out nothing and runs no code from the pull request.
on:
  pull_request_target:
    types: [closed]
permissions:
  actions: write
jobs:
  cancel:
    runs-on: ubuntu-latest
    steps:
      - name: Cancel the pull request's unfinished runs
        env:
          GH_TOKEN: ${{ github.token }}
          REPO: ${{ github.repository }}
          BRANCH: ${{ github.event.pull_request.head.ref }}
          SHA: ${{ github.event.pull_request.head.sha }}
        run: |
          for status in queued in_progress waiting pending requested; do
            gh run list -R "$REPO" --branch "$BRANCH" --status "$status" --limit 100 \
              --json databaseId,event,headSha \
              -q ".[] | select(.event == \"pull_request\" and .headSha == \"$SHA\") | .databaseId"
          done | sort -u | while read -r id; do
            gh run cancel -R "$REPO" "$id" || true
          done