Calendar::hasHoliday

public function hasHoliday(DateTime $date)
{
	$exclusionDates = $this->obtainFinalExclusions();
	$year = $date->format('Y');
	$month = $date->format('n');
	$day = $date->format('j');
	return array_key_exists($year, $exclusionDates) &&
		   array_key_exists($month, $exclusionDates[$year]) &&
		   array_key_exists($day, $exclusionDates[$year][$month]);
}