mdm\admin\models\AuthItem::unique PHP Метод

    public function unique()
    {
        $authManager = Configs::authManager();
        $value = $this->name;
        if ($authManager->getRole($value) !== null || $authManager->getPermission($value) !== null) {
            $message = Yii::t('yii', '{attribute} "{value}" has already been taken.');
            $params = ['attribute' => $this->getAttributeLabel('name'), 'value' => $value];
            $this->addError('name', Yii::$app->getI18n()->format($message, $params, Yii::$app->language));
        }
    }