BooleanData.php

<?php

namespace Drupal\Core\TypedData\Plugin\DataType;

use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\Core\TypedData\Attribute\DataType;
use Drupal\Core\TypedData\PrimitiveBase;
use Drupal\Core\TypedData\Type\BooleanInterface;

/**
 * The boolean data type.
 *
 * The plain value of a boolean is a regular PHP boolean. For setting the value
 * any PHP variable that casts to a boolean may be passed.
 */
class BooleanData extends PrimitiveBase implements BooleanInterface {
  
  /**
   * {@inheritdoc}
   */
  public function getCastedValue() {
    return (bool) $this->value;
  }

}