business\Holidays::isHoliday PHP Method

    public function isHoliday(\DateTime $date)
    {
        return $this->holidays->contains($date);
    }

 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')));
 }