Issue #3156542 by alexpott, voleger, andypost, Charlie ChX Negyesi, Gábor Hojtsy, longwave: \ReflectionParameter::getClass() is deprecated in PHP 8.0

core/lib/Drupal/Component/Utility/ArgumentsResolver.php

@@ -69,7 +69,7 @@ class ArgumentsResolver implements ArgumentsResolverInterface {
    *   Thrown when there is a missing parameter.
    */
   protected function getArgument(\ReflectionParameter $parameter) {
-    $parameter_type_hint = $parameter->getClass();
+    $parameter_type_hint = Reflection::getParameterClassName($parameter);
     $parameter_name = $parameter->getName();
 
     // If the argument exists and is NULL, return it, regardless of
@@ -79,6 +79,7 @@ class ArgumentsResolver implements ArgumentsResolverInterface {
     }
 
     if ($parameter_type_hint) {
+      $parameter_type_hint = new \ReflectionClass($parameter_type_hint);
       // If the argument exists and complies with the type hint, return it.
       if (isset($this->objects[$parameter_name]) && is_object($this->objects[$parameter_name]) && $parameter_type_hint->isInstance($this->objects[$parameter_name])) {
         return $this->objects[$parameter_name];

core/lib/Drupal/Component/Utility/Reflection.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Drupal\Component\Utility;
+
+/**
+ * Provides helper methods for reflection.
+ */
+final class Reflection {
+
+  /**
+   * Gets the parameter's class name.
+   *
+   * @param \ReflectionParameter $parameter
+   *   The parameter.
+   *
+   * @return string|null
+   *   The parameter's class name or NULL if the parameter is not a class.
+   */
+  public static function getParameterClassName(\ReflectionParameter $parameter) : ?string {
+    $name = NULL;
+    if ($parameter->hasType() && !$parameter->getType()->isBuiltin()) {
+      $name = $parameter->getType()->getName();
+      $lc_name = strtolower($name);
+      switch ($lc_name) {
+        case 'self':
+          return $parameter->getDeclaringClass()->getName();
+
+        case 'parent':
+          return ($parent = $parameter->getDeclaringClass()->getParentClass()) ? $parent->name : NULL;
+      }
+    }
+    return $name;
+  }
+
+}

core/lib/Drupal/Core/DependencyInjection/Compiler/TaggedHandlersPass.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\Core\DependencyInjection\Compiler;
 
+use Drupal\Component\Utility\Reflection;
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Exception\LogicException;
@@ -130,8 +131,9 @@ class TaggedHandlersPass implements CompilerPassInterface {
     $priority_pos = NULL;
     $extra_params = [];
     foreach ($params as $pos => $param) {
-      if ($param->getClass()) {
-        $interface = $param->getClass();
+      $class = Reflection::getParameterClassName($param);
+      if ($class !== NULL) {
+        $interface = $class;
       }
       elseif ($param->getName() === 'id') {
         $id_pos = $pos;
@@ -152,7 +154,6 @@ class TaggedHandlersPass implements CompilerPassInterface {
         $method_name,
       ]));
     }
-    $interface = $interface->getName();
 
     // Find all tagged handlers.
     $handlers = [];

core/lib/Drupal/Core/Entity/EntityResolverManager.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\Core\Entity;
 
+use Drupal\Component\Utility\Reflection;
 use Drupal\Core\DependencyInjection\ClassResolverInterface;
 use Symfony\Component\Routing\Route;
 
@@ -139,7 +140,8 @@ class EntityResolverManager {
       if (isset($entity_types[$parameter_name])) {
         $entity_type = $entity_types[$parameter_name];
         $entity_class = $entity_type->getClass();
-        if (($reflection_class = $parameter->getClass()) && (is_subclass_of($entity_class, $reflection_class->name) || $entity_class == $reflection_class->name)) {
+        $reflection_class = Reflection::getParameterClassName($parameter);
+        if ($reflection_class && (is_subclass_of($entity_class, $reflection_class) || $entity_class == $reflection_class)) {
           $parameter_definitions += [$parameter_name => []];
           $parameter_definitions[$parameter_name] += [
             'type' => 'entity:' . $parameter_name,

core/tests/Drupal/Tests/Component/Utility/ReflectionTest.php

@@ -0,0 +1,54 @@
+<?php
+
+namespace Drupal\Tests\Component\Utility;
+
+use Drupal\Component\Utility\Reflection;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @coversDefaultClass \Drupal\Component\Utility\Reflection
+ * @group Utility
+ */
+class ReflectionTest extends TestCase {
+
+  /**
+   * @param string|null $expected
+   * @param \ReflectionParameter $parameter
+   *
+   * @covers ::getParameterClassName
+   * @dataProvider providerGetParameterClassName
+   */
+  public function testGetParameterClassName(?string $expected, \ReflectionParameter $parameter) {
+    $this->assertEquals($expected, Reflection::getParameterClassName($parameter));
+  }
+
+  /**
+   * Data provider for ::testGetParameterClassName().
+   *
+   * @return array[]
+   */
+  public function providerGetParameterClassName() {
+    $reflection_method = new \ReflectionMethod(static::class, 'existsForTesting');
+    $parameters = $reflection_method->getParameters();
+    return [
+      'string' => [NULL, $parameters[0]],
+      'array' => [NULL, $parameters[1]],
+      'same class' => ['Drupal\Tests\Component\Utility\ReflectionTest', $parameters[2]],
+      'class' => ['Drupal\Component\Utility\Reflection', $parameters[3]],
+      'parent' => ['PHPUnit\Framework\TestCase', $parameters[4]],
+      'self' => ['Drupal\Tests\Component\Utility\ReflectionTest', $parameters[5]],
+    ];
+  }
+
+  /**
+   * This method exists for reflection testing only.
+   *
+   * Note the capital P in Parent is intentional and for testing purposes.
+   */
+  // phpcs:disable Generic.PHP.LowerCaseKeyword.Found
+  protected function existsForTesting(string $string, array $array, ReflectionTest $test, Reflection $reflection, Parent $parent, self $self) {
+  }
+
+  // phpcs:enable
+
+}