CommentNameConstraint.php

<?php

namespace Drupal\comment\Plugin\Validation\Constraint;

use Drupal\Core\Entity\Plugin\Validation\Constraint\CompositeConstraintBase;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\Core\Validation\Attribute\Constraint;

/**
 * Supports validating comment author names.
 */
class CommentNameConstraint extends CompositeConstraintBase {
    
    /**
     * Message shown when an anonymous user comments using a registered name.
     *
     * @var string
     */
    public $messageNameTaken = 'The name you used (%name) belongs to a registered user.';
    
    /**
     * Message shown when an admin changes the comment-author to an invalid user.
     *
     * @var string
     */
    public $messageRequired = 'You have to specify a valid author.';
    
    /**
     * Message shown when the name doesn't match the author's name.
     *
     * @var string
     */
    public $messageMatch = 'The specified author name does not match the comment author.';
    
    /**
     * {@inheritdoc}
     */
    public function coversFields() {
        return [
            'name',
            'uid',
        ];
    }

}