business\Holidays::addHolidays PHP Method

    public function addHolidays($holidays)
    {
        foreach ($holidays as $holiday) {
            if ($holiday instanceof DateRange) {
                $this->addHolidays($holiday);
                continue;
            }
            $this->addHoliday($holiday);
        }
    }

 public function testAddHolidays()
 {
     $holiday = new \DateTime('2015-05-11');
     $holidayRange = new DateRange(new \DateTime('2015-07-08'), new \DateTime('2015-07-21'));
     $holidays = new Holidays();
     $holidays->addHolidays([$holiday]);
     $holidays->addHolidays($holidayRange);
     $this->assertTrue($holidays->isHoliday($holiday));
     $this->assertTrue($holidays->isHoliday(new \DateTime('2015-07-09 10:00')));
 }