protected function isDateAttribute($attribute)
{
switch ($attribute) {
case 'LeapYear':
return (bool) $this->format('L');
break;
case 'AmOrPm':
return $this->format('A');
break;
case 'DaylightSavings':
return (bool) $this->format('I');
break;
}
throw new InvalidArgumentException('The date attribute [' . $attribute . '] could not be found.');
}