validate_pr.yml

name: Validate PR
on: pull_request

defaults:
  run:
    shell: bash
    working-directory: project

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      # checkout code
      - name: Checkout
        uses: actions/checkout@v4
        with:
          path: project
          fetch-depth: 2
      # checkout schema as xmllint can't https 
      - name: Checkout schema repo
        uses: actions/checkout@v4
        with:
          repository: BetaMasaheft/Schema
          path: schema
      - name: Install Test Dependencies
        run: |
          sudo apt-get update
          sudo apt-get install -y libxml2-utils
      # Compare locally changed files to PR's base
      - name: Check for changed source files
        id: changed
        run: |
          {
            echo "FILES=$(git diff --name-only --diff-filter=ACMRT \
            ${{ github.event.pull_request.base.sha }} \
            ${{ github.sha }} \
            -- ':./**/*.xml' ':!*/transkribus*.xml' ':!*/facsimile*.xml' \
            ':!./**/edition.xml' ':!./**/msDesc.xml' ':!./**/*text.xml' \
            ':!./**/taxonomy.xml' ':*.xml' ':!build.xml' ':!expath-pkg.xml' ':!repo.xml' | xargs)"     
          } >> "$GITHUB_OUTPUT"
      # If no xml files were modified ...
      - name: No source files changed
        if: ${{ steps.changed.outputs.FILES == '' }}
        run: |
          echo "All good"
      # ... otherwise
      - name: List modified documents
        env:
          FILES: ${{ steps.changed.outputs.FILES }}
        if: ${{ steps.changed.outputs.FILES != '' }}  
        run: |
          echo "modified: $FILES"
      # Validate changed files against latest schema
      - name: Validate changed source files
        env:
          FILES: ${{ steps.changed.outputs.FILES }}
        if: ${{ steps.changed.outputs.FILES != '' }}
        run: |
          xmllint \
            --noout --xinclude --nowarning \
            --relaxng ../schema/tei-betamesaheft.rng \
            $FILES \
            2>&1 | \
            { grep -vE 'RNG|validates' || :; }
      # ensure branch contains only well-formed xml files 
      - name: Ensure all XML files are well formed
        run: |
          xmllint --noout \
            $(find . -type f -name '*.xml')