TestDataType.php

<?php

declare (strict_types=1);
namespace Drupal\Tests\Core\Plugin\Fixtures\Plugin\DataType;

use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\Core\TypedData\Attribute\DataType;
use Drupal\Core\TypedData\TypedData;

/**
 * Provides a test data type.
 */
class TestDataType extends TypedData {
  
  /**
   * Required by the parent class.
   *
   * @var mixed
   */
  protected $value;

}