When\When::bymonthday PHP Method

    public function bymonthday($bymodaylist, $delimiter = ",")
    {
        if ($this->bymonthdays = self::prepareItemsList($bymodaylist, $delimiter, 'monthDayNum')) {
            return $this;
        }
        throw new \InvalidArgumentException("bymonthday: Accepts positive and negative values between 1 and 31");
    }

 /**
  * @expectedException InvalidArgumentException
  */
 public function testInvalidByMonthDay()
 {
     $test = new When();
     $test->bymonthday(32);
 }