code: public function isExpired($now)
      {
          if (! $this->expiry) {
              return true;
          }
          if (is_string($now)) {
              $now = strtotime($now);
          }
  
          return ($this->expiry < $now);
      }
docs: Test to see if cookie is expired against the cookie format time or timestamp.
  Will give true for a session cookie.
  
  @param integer/string $now Time to test against. Result will be false if this time
  is later than the cookie expiry. Can be either a timestamp
  integer or a cookie format date.