public function grantToRole($permission, $role)
    {
        /** @var EloquentRole $roleModel */
        if ( ! ($roleModel = $this->sentinel->findRoleBySlug($role))) {
            return false;
        }

        $permissions = is_array($permission) ? $permission : [ $permission ];

        foreach ($permissions as $singlePermission) {
            $this->grantSinglePermissionToRole($singlePermission, $roleModel);
        }

        if ( ! $roleModel->save()) {
            // @codeCoverageIgnoreStart
            return false;
            // @codeCoverageIgnoreEnd
        }

        $this->fireRoleChangeEvent();
        return true;
    }