Issue #3185603 by daffie, longwave, joachim: [Symfony 5] Symfony Constraint...

<?php

namespace Drupal\Core\Validation;

use Drupal\Core\Plugin\Factory\ContainerFactory;

use Symfony\Component\Validator\Constraint;

use Drupal\Core\Plugin\ContainerFactoryPluginInterface;

/**

 * Constraint plugin factory.

 *

 * Symfony Constraint plugins are created as Drupal plugins, but the default

 * plugin constructor is not compatible.

 */

class ConstraintFactory extends ContainerFactory {

  /**

   * {@inheritdoc}

   */

  public function createInstance($plugin_id, array $configuration = []) {

    $plugin_definition = $this->discovery->getDefinition($plugin_id);

    $plugin_class = static::getPluginClass($plugin_id, $plugin_definition, $this->interface);

    // If the plugin provides a factory method, pass the container to it.

    if (is_subclass_of($plugin_class, ContainerFactoryPluginInterface::class)) {

      return $plugin_class::create(\Drupal::getContainer(), $configuration, $plugin_id, $plugin_definition);

    }

    // If the plugin is a Symfony Constraint, use the correct constructor.

    if (is_subclass_of($plugin_class, Constraint::class)) {

      return new $plugin_class($configuration);

    }

    // Otherwise, create the plugin as normal.

    return new $plugin_class($configuration, $plugin_id, $plugin_definition);

  }

}

   *   The module handler to invoke the alter hook with.

   */

  public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler) {

    $this->factory = new ConstraintFactory($this);

    parent::__construct('Plugin/Validation/Constraint', $namespaces, $module_handler, NULL, 'Drupal\Core\Validation\Annotation\Constraint');

    $this->alterInfo('validation_constraint');

    $this->setCacheBackend($cache_backend, 'validation_constraint_plugins');

<?php

namespace Drupal\entity_test\Plugin\Validation\Constraint;

use Drupal\Component\Plugin\PluginBase;

use Drupal\Core\Plugin\ContainerFactoryPluginInterface;

use Symfony\Component\DependencyInjection\ContainerInterface;

/**

 * A dummy constraint for testing \Drupal\Core\Validation\ConstraintFactory.

 *

 * @Constraint(

 *   id = "EntityTestContainerFactoryPlugin",

 *   label = @Translation("Constraint that implements ContainerFactoryPluginInterface."),

 *   type = "entity"

 * )

 */

class EntityTestContainerFactoryPlugin extends PluginBase implements ContainerFactoryPluginInterface {

  /**

   * {@inheritdoc}

   */

  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {

    return new static(

      $configuration,

      $plugin_id,

      $plugin_definition,

    );

  }

}

<?php

namespace Drupal\entity_test\Plugin\Validation\Constraint;

use Drupal\Component\Plugin\PluginBase;

/**

 * A dummy constraint for testing \Drupal\Core\Validation\ConstraintFactory.

 *

 * @Constraint(

 *   id = "EntityTestDefaultPlugin",

 *   label = @Translation("Constraint that extends PluginBase."),

 *   type = "entity"

 * )

 */

class EntityTestDefaultPlugin extends PluginBase {}

<?php

namespace Drupal\KernelTests\Core\Validation;

use Drupal\Component\Plugin\PluginBase;

use Drupal\Core\Plugin\ContainerFactoryPluginInterface;

use Drupal\KernelTests\KernelTestBase;

use Symfony\Component\Validator\Constraint;

/**

 * @coversDefaultClass \Drupal\Core\Validation\ConstraintFactory

 *

 * @group Validation

 */

class ConstraintFactoryTest extends KernelTestBase {

  /**

   * {@inheritdoc}

   */

  protected static $modules = ['entity_test'];

  /**

   * @covers ::createInstance

   */

  public function testCreateInstance() {

    $constraint_manager = \Drupal::typedDataManager()->getValidationConstraintManager();

    // If the plugin is a \Symfony\Component\Validator\Constraint, they will be

    // created first.

    $this->assertInstanceOf(Constraint::class, $constraint_manager->create('Uuid', []));

    // If the plugin implements the

    // \Drupal\Core\Plugin\ContainerFactoryPluginInterface, they will be created

    // second.

    $container_factory_plugin = $constraint_manager->create('EntityTestContainerFactoryPlugin', []);

    $this->assertNotInstanceOf(Constraint::class, $container_factory_plugin);

    $this->assertInstanceOf(ContainerFactoryPluginInterface::class, $container_factory_plugin);

    // Plugins that are not a \Symfony\Component\Validator\Constraint or do not

    // implement the \Drupal\Core\Plugin\ContainerFactoryPluginInterface are

    // created last.

    $default_plugin = $constraint_manager->create('EntityTestDefaultPlugin', []);

    $this->assertNotInstanceOf(Constraint::class, $default_plugin);

    $this->assertNotInstanceOf(ContainerFactoryPluginInterface::class, $default_plugin);

    $this->assertInstanceOf(PluginBase::class, $default_plugin);

  }

}