pocketmine\permission\PermissibleBase::isPermissionSet PHP Method

    public function isPermissionSet($name)
    {
        return isset($this->permissions[$name instanceof Permission ? $name->getName() : $name]);
    }

 /**
  * @param permission\Permission|string $name
  *
  * @return bool
  */
 public function isPermissionSet($name)
 {
     return $this->perm->isPermissionSet($name);
 }