/**
* Sets login for the user. It could be set if it fits the format, user isn't a guest,
* and there is no user with the same login.
*
* @param new user login
* @return null
* @throws UserException in case of errors
*/
public function setLogin($new_login)
{
if (!PasswordAuth::checkLoginFormat($new_login)) {
throw new UserException("Incorrect login parameter");
}
if ($this->id == self::GUEST) {
throw new UserException("Cannot change login for guest user. Use User::add instead");
}
if (self::findBy("login", $new_login) !== null) {
throw new UserException("User with login '{$new_login}' already exists");
}
$this->login = $new_login;
}
