test(phpunit): Enable PHP 8 testing with a PHPUnit compatibility layer (#/3222962 by klausi)

.github/workflows/testing.yml

@@ -7,7 +7,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php-versions: ['7.1', '7.2', '7.3', '7.4']
+        php-versions: ['7.1', '7.2', '7.3', '7.4', '8.0']
         phpstan: ['1']
         # Extra run to also test on PHP 7.0 without PHPStan.
         include:

composer.json

@@ -27,7 +27,7 @@
         }
     },
     "require-dev": {
-        "phpunit/phpunit": "^6.0 || ^7.0",
+        "phpunit/phpunit": "^6.0 || ^7.0 || ^8.0",
         "phpstan/phpstan": "^0.12.63"
     }
 }

phpstan.neon

@@ -10,6 +10,8 @@ parameters:
         - 'tests/*/good.php'
         - 'tests/*/bad.php'
         - 'tests/*/drupal[678]/*.php'
+        # Compatibilty layer class for PHPUnit that should not be checked.
+        - 'tests/Drupal/PhpunitCompatibilityTestCase.php'
     bootstrapFiles:
         - tests/Drupal/phpunit-bootstrap.php
         # PHPStan does not find the constants in this file, so load it manually.

tests/Drupal/CoderSniffUnitTest.php

@@ -19,9 +19,8 @@ use PHP_CodeSniffer\Files\LocalFile;
 use PHP_CodeSniffer\Exceptions\RuntimeException;
 use PHP_CodeSniffer\Util\Common;
 use PHP_CodeSniffer\Util\Tokens;
-use PHPUnit\Framework\TestCase;
 
-abstract class CoderSniffUnitTest extends TestCase
+abstract class CoderSniffUnitTest extends PhpunitCompatibilityTestCase
 {
 
     /**
@@ -60,7 +59,7 @@ abstract class CoderSniffUnitTest extends TestCase
      *
      * @return void
      */
-    protected function setUp()
+    protected function compatibleSetUp()
     {
         $class = get_class($this);
 
@@ -76,7 +75,7 @@ abstract class CoderSniffUnitTest extends TestCase
             define('PHP_CODESNIFFER_CBF', 0);
         }
 
-    }//end setUp()
+    }//end compatibleSetUp()
 
 
     /**

tests/Drupal/PhpunitCompatibilityTestCase.php

+<?php
+/**
+ * Helper class to be compatible with different PHPUnit major versions.
+ *
+ * We want to support PHP 7.0 which does not have the "void" return type hint.
+ * For PHP 8 we need a higher PHPUnit version that enforces the type hint. Our
+ * solution is to define a compatibility class depending on PHP version. It
+ * routes around the setup method with a compatibleSetUp() method that child
+ * classes use.
+ */
+
+namespace Drupal\Test;
+
+use PHPUnit\Framework\TestCase;
+
+if (version_compare(PHP_VERSION, '7.1.0') >= 0) {
+    class PhpunitCompatibilityTestCase extends TestCase
+    {
+
+
+        /**
+         * {@inheritdoc}
+         *
+         * @return void
+         */
+        protected function setUp(): void
+        {
+            $this->compatibleSetUp();
+
+        }//end setUp()
+
+
+        /**
+         * Helper method that is used in place of ::setUp().
+         *
+         * @return void
+         */
+        protected function compatibleSetUp()
+        {
+
+        }//end compatibleSetUp()
+
+
+    }//end class
+
+} else {
+    class PhpunitCompatibilityTestCase extends TestCase
+    {
+
+
+        /**
+         * {@inheritdoc}
+         *
+         * @return void
+         */
+        protected function setUp()
+        {
+            $this->compatibleSetUp();
+
+        }//end setUp()
+
+
+        /**
+         * Helper method that is used in place of ::setUp().
+         *
+         * @return void
+         */
+        protected function compatibleSetUp()
+        {
+
+        }//end compatibleSetUp()
+
+
+    }//end class
+
+}//end if

tests/Drupal/phpunit-bootstrap.php

 <?php
 
 require 'vendor/autoload.php';
+require 'tests/Drupal/PhpunitCompatibilityTestCase.php';
 require 'tests/Drupal/CoderSniffUnitTest.php';
 require 'vendor/squizlabs/php_codesniffer/autoload.php';

tests/DrupalPractice/ProjectDetection/ProjectUnitTest.php

@@ -2,13 +2,13 @@
 
 namespace DrupalPractice\Test\ProjectDetection;
 
+use Drupal\Test\PhpunitCompatibilityTestCase;
 use DrupalPractice\Project;
-use PHPUnit\Framework\TestCase;
 
 /**
  * Tests that project and version detection works.
  */
-class ProjectUnitTest extends TestCase
+class ProjectUnitTest extends PhpunitCompatibilityTestCase
 {
 
     /**
@@ -24,14 +24,13 @@ class ProjectUnitTest extends TestCase
      *
      * @return void
      */
-    public function setUp()
+    protected function compatibleSetUp()
     {
-        parent::setUp();
         $this->phpcsFile = $this->getMockBuilder('\PHP_CodeSniffer\Files\File')
             ->disableOriginalConstructor()
             ->getMock();
 
-    }//end setUp()
+    }//end compatibleSetUp()
 
 
     /**