GH Actions: run tests against PHPUnit PHAR files as well

PHPUnit 8.5.38 and 9.6.19 contain a change in the PHAR build process, which means that classes external to PHPUnit are now prefixed differently, which breaks one polyfill.

As things were, such issues would previously not be caught by CI.

This commit adds a new job to the test workflow, which will run the tests against a range of PHP-PHPUnit combinations using the PHPUnit Phar to ensure any such issues will be automatically caught in the future.

The new test workflow will (very) selectively also upload code coverage to safeguard that the PHAR-file specific lines in the code base remain covered by tests as well.

.github/workflows/test.yml

@@ -146,8 +146,185 @@ jobs:
           flag-name: php-${{ matrix.php }}-phpunit-${{ matrix.phpunit }}
           parallel: true
 
+  test-phar:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        include:
+          # Test against the high/low supported PHP-PHPUnit combinations.
+          #
+          # Code coverage is only run against the high/high PHP-PHPUnit combinations
+          # and very select other combinations.
+          # This should be sufficient to record the coverage for the PHAR specific code.
+
+          # PHPUnit 4 is only supported at the latest version.
+          - php: '5.4'
+            phpunit: '4'
+          - php: '5.5'
+            phpunit: '4'
+          - php: '5.6'
+            phpunit: '4'
+            coverage: true
+
+          # PHPUnit 5 is only supported for PHPUnit 5.7.21-latest.
+          - php: '5.6'
+            phpunit: '5.7.21'
+          - php: '5.6'
+            phpunit: '5'
+          - php: '7.1'
+            phpunit: '5.7.21'
+          - php: '7.1'
+            phpunit: '5'
+            coverage: true
+
+          # PHPUnit 6 is fully supported for the officially supported PHP versions.
+          - php: '7.0'
+            phpunit: '6.0'
+          - php: '7.0'
+            phpunit: '6'
+          - php: '7.2'
+            phpunit: '6.0'
+          - php: '7.2'
+            phpunit: '6'
+            coverage: true
+
+          # PHPUnit 7 is fully supported for the officially supported PHP versions.
+          # Caveats:
+          # - PHPUnit 7.0 seems to have an issue with something related to TestListeners, so using PHPUnit 7.1 instead for "low".
+          # - PHPUnit 7 supports PHP 7.3 as of PHPUnit 7.3.0 (for our purposes).
+          - php: '7.1'
+            phpunit: '7.1'
+          - php: '7.1'
+            phpunit: '7'
+          - php: '7.3'
+            phpunit: '7.3'
+          - php: '7.3'
+            phpunit: '7'
+            coverage: true
+
+          # PHPUnit 8 is fully supported for the officially supported PHP versions.
+          # Caveats:
+          # - PHPUnit 8 supports PHP 8.0 as of PHPUnit 8.5.12 (for our purposes).
+          # - PHPUnit 8 supports PHP 8.1 as of PHPUnit 8.5.19 (for our purposes).
+          # - PHPUnit 8 supports PHP 8.2 as of PHPUnit 8.5.19 (for our purposes).
+          # - PHPUnit 8 supports PHP 8.3 as of PHPUnit 8.5.19 (for our purposes).
+          # - PHPUnit 8 does not support running code coverage on PHP 8.0 or higher.
+          - php: '7.2'
+            phpunit: '8.0'
+            coverage: true
+          - php: '7.2'
+            phpunit: '8'
+          - php: '7.4'
+            phpunit: '8.0'
+          - php: '7.4'
+            phpunit: '8'
+            coverage: true
+          - php: '8.0'
+            phpunit: '8.5.12'
+          - php: '8.0'
+            phpunit: '8'
+          - php: '8.3'
+            phpunit: '8.5.19'
+          - php: '8.3'
+            phpunit: '8'
+
+          # PHPUnit 9 is fully supported for the officially supported PHP versions.
+          # Caveats:
+          # - PHPUnit 9 supports PHP 8.0 as of PHPUnit 9.3.0 (for our purposes).
+          # - PHPUnit 9 supports PHP 8.1 as of PHPUnit 9.5.8 (for our purposes).
+          # - PHPUnit 9 supports PHP 8.2 as of PHPUnit 9.5.8 (for our purposes).
+          # - PHPUnit 9 supports PHP 8.3 as of PHPUnit 9.5.8 (for our purposes).
+          - php: '7.3'
+            phpunit: '9.0'
+            coverage: true
+          - php: '7.3'
+            phpunit: '9'
+          - php: '8.0'
+            phpunit: '9.3.0'
+          - php: '8.0'
+            phpunit: '9'
+          - php: '8.1'
+            phpunit: '9.5.8'
+          - php: '8.1'
+            phpunit: '9'
+          - php: '8.2'
+            phpunit: '9.5.8'
+          - php: '8.2'
+            phpunit: '9'
+          - php: '8.3'
+            phpunit: '9.5.8'
+          - php: '8.3'
+            phpunit: '9'
+            coverage: true
+
+          # Experimental builds.
+          - php: '8.4'
+            phpunit: '9'
+
+    name: "PHAR test: PHP ${{ matrix.php }} - PHPUnit: ${{matrix.phpunit}}"
+
+    continue-on-error: ${{ matrix.php == '8.4' }}
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Install PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          ini-values: zend.assertions=1, error_reporting=-1, display_errors=On
+          tools: phpunit:${{ matrix.phpunit }}
+          coverage: ${{ matrix.coverage && 'xdebug' || 'none' }}
+        env:
+          fail-fast: true
+
+      # YoastCS 3.0 has a PHP 7.2 minimum which conflicts with the requirements of this package.
+      - name: 'Composer: remove YoastCS'
+        run: composer remove --dev yoast/yoastcs --no-update --no-interaction
+
+      # Remove PHPUnit from the Composer install as we want to be sure the PHAR file is used.
+      - name: 'Composer: remove PHPUnit'
+        run: composer remove phpunit/phpunit --no-update --no-interaction
+
+      # Install dependencies and handle caching in one go.
+      # @link https://github.com/marketplace/actions/install-php-dependencies-with-composer
+      - name: Install Composer dependencies - normal
+        if: matrix.php < '8.3'
+        uses: "ramsey/composer-install@v3"
+        with:
+          composer-options: "--no-dev"
+          # Bust the cache at least once a month - output format: YYYY-MM.
+          custom-cache-suffix: $(date -u "+%Y-%m")
+
+      - name: Install Composer dependencies - ignore PHP restrictions
+        if: matrix.php >= '8.3'
+        uses: "ramsey/composer-install@v3"
+        with:
+          composer-options: "--no-dev --ignore-platform-req=php+"
+          # Bust the cache at least once a month - output format: YYYY-MM.
+          custom-cache-suffix: $(date -u "+%Y-%m")
+
+      - name: Run the unit tests
+        if: ${{ ! matrix.coverage }}
+        run: phpunit --no-coverage
+
+      - name: Run the unit tests with code coverage
+        if: ${{ matrix.coverage }}
+        run: phpunit
+
+      - name: Upload coverage results to Coveralls
+        if: ${{ success() && matrix.coverage == true }}
+        uses: coverallsapp/github-action@v2
+        with:
+          file: build/logs/clover.xml
+          format: clover
+          flag-name: php-${{ matrix.php }}-phpunit-phar-${{ matrix.phpunit }}
+          parallel: true
+
   coveralls-finish:
-    needs: test
+    needs: [test, test-phar]
     runs-on: ubuntu-latest
 
     steps: