name: Lint GitHub Actions Workflows
on:
  pull_request:
    paths:
      - '.github/**'
    types: [opened, synchronize, reopened, ready_for_review]

# cancel existing runs of the same workflow on the same ref
concurrency:
  group: ${{ github.workflow }}-${{ github.head_ref || github.ref }}
  cancel-in-progress: true

jobs:
  actionlint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
      - name: "Check workflow files"
        uses: docker://docker.mirror.hashicorp.services/rhysd/actionlint@sha256:93834930f56ca380be3e9a3377670d7aa5921be251b9c774891a39b3629b83b8
        with:
          # milestoned and demilestoned work (https://github.com/github/docs/issues/23909) but they aren't listed in the github documentation, so actionlint complains about them 
          args: "-ignore=\"invalid activity type \\\"demilestoned\\\" for \\\"pull_request\\\" Webhook event\" -ignore=\"invalid activity type \\\"milestoned\\\" for \\\"pull_request\\\" Webhook event\""