EntitySerializedField.php

<?php

declare (strict_types=1);
namespace Drupal\entity_test\Entity;

use Drupal\Core\Entity\Attribute\ContentEntityType;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\Core\Entity\EntityTypeInterface;
use Drupal\Core\Field\BaseFieldDefinition;

/**
 * Defines a test class for testing fields with a serialized column.
 */
class EntitySerializedField extends EntityTest {
    
    /**
     * {@inheritdoc}
     */
    public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
        $fields = parent::baseFieldDefinitions($entity_type);
        $fields['serialized'] = BaseFieldDefinition::create('serialized_item_test')->setLabel(t('Serialized'));
        $fields['serialized_text'] = BaseFieldDefinition::create('serialized_property_item_test')->setLabel(t('Serialized text'));
        $fields['serialized_long'] = BaseFieldDefinition::create('string_long')->setLabel(t('Serialized long string'));
        return $fields;
    }

}