name: Check Markdown links

on:
  push:
    branches:
      - main
  pull_request:
    branches: [main]

jobs:
  markdown-link-check:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - uses: technote-space/get-diff-action@v6
        with:
          PATTERNS: |
            **/**.md
      - uses: creachadair/github-action-markdown-link-check@master
        with:
          check-modified-files-only: 'yes'
          config-file: '.md-link-check.json'
        if: env.GIT_DIFF