name: modified_scripts
on: [pull_request]
jobs:
  discover_modified_scripts:
    runs-on: ubuntu-latest
    outputs:
      versions: ${{steps.modified-versions.outputs.versions}}
    steps:
      - uses: actions/checkout@v2
      - run: git fetch origin "$GITHUB_BASE_REF"
      - shell: bash
        run: >
          versions=$(git diff "origin/$GITHUB_BASE_REF" --name-only -z
          | perl -ne 'BEGIN {$\="\n";$/="\0";} chomp;
            if (/^plugins\/python-build\/share\/python-build\/(?:([^\/]+)|patches\/([^\/]+)\/.*)$/)
                { print $1.$2; }' \
          | sort -u);
          echo -e "versions<<!\\n$versions\\n!" >> $GITHUB_ENV
      - id: modified-versions
        run: |
          echo -n "::set-output name=versions::"
          echo "${{ env.versions }}" | jq -R . | jq -sc .
  macos_build:
    needs: discover_modified_scripts
    if: needs.discover_modified_scripts.outputs.versions != '[""]'
    strategy:
      fail-fast: false
      matrix:
        python-version: ${{fromJson(needs.discover_modified_scripts.outputs.versions)}}
        os: ["macos-10.15", "macos-11"]
    runs-on: ${{ matrix.os }}
    steps:
      - uses: actions/checkout@v2
      - run: |
          brew install openssl openssl@1.1 readline sqlite3 xz zlib
      - run: |
          export PYENV_ROOT="$GITHUB_WORKSPACE"
          echo "PYENV_ROOT=$PYENV_ROOT" >> $GITHUB_ENV
          echo "$PYENV_ROOT/shims:$PYENV_ROOT/bin" >> $GITHUB_PATH
      - run: |
          pyenv install ${{ matrix.python-version }}
          pyenv global ${{ matrix.python-version }}
      - run: |
          python --version
          python -m pip --version
      - shell: python  # Prove that actual Python == expected Python
        env:
          EXPECTED_PYTHON: ${{ matrix.python-version }}
        run: |
          import os, sys, os.path
          correct_dir = os.path.join(
              os.environ['PYENV_ROOT'],
              'versions',
              os.environ['EXPECTED_PYTHON'],
              'bin')
          assert os.path.dirname(sys.executable) == correct_dir
      # bundled executables in some Anaconda releases cause the post-run step to hang in MacOS
      - run: |
          pyenv global system
          rm -f "$(pyenv root)"/shims/*

  ubuntu_build:
    needs: discover_modified_scripts
    if: needs.discover_modified_scripts.outputs.versions != '[""]'
    strategy:
      fail-fast: false
      matrix:
        python-version: ${{fromJson(needs.discover_modified_scripts.outputs.versions)}}
        os: ["ubuntu-18.04", "ubuntu-20.04"]
    runs-on: ${{ matrix.os }}
    steps:
      - uses: actions/checkout@v2
      - run: |
          sudo apt-get update -q; sudo apt-get install -yq build-essential \
            libssl-dev zlib1g-dev libbz2-dev libreadline-dev libsqlite3-dev \
            wget curl llvm libncurses5-dev libncursesw5-dev \
            xz-utils tk-dev libffi-dev liblzma-dev python-openssl git
      - run: |
          export PYENV_ROOT="$GITHUB_WORKSPACE"
          echo "PYENV_ROOT=$PYENV_ROOT" >> $GITHUB_ENV
          echo "$PYENV_ROOT/shims:$PYENV_ROOT/bin" >> $GITHUB_PATH
      - run: |
          pyenv install ${{ matrix.python-version }}
          pyenv global ${{ matrix.python-version }}
      - run: python --version
      - run: python -m pip --version
      - shell: python  # Prove that actual Python == expected Python
        env:
          EXPECTED_PYTHON: ${{ matrix.python-version }}
        run: |
          import os, sys, os.path
          correct_dir = os.path.join(
              os.environ['PYENV_ROOT'],
              'versions',
              os.environ['EXPECTED_PYTHON'],
              'bin')
          assert os.path.dirname(sys.executable) == correct_dir