Twig extension - Filter for month number

gistfile1.txt

/**
 * getFilter
 */
public function getFilters ( )
{
  return array (
    'month_name' => new \Twig_Filter_Method ( $this , 'get_month_name' )
  ) ;
}

/**
 * get_month_name
 */
public function get_month_name ( $aMonthNumber )
{
  switch ( $aMonthNumber )
  {
    case '1' :
      $monthName = 'january' ;
      break ;
    case '2' :
      $monthName = 'february' ;
      break ;
    case '3' :
      $monthName = 'march' ;
      break ;
    case '4' :
      $monthName = 'april' ;
      break ;
    case '5' :
      $monthName = 'may' ;
      break ;
    case '6' :
      $monthName = 'june' ;
      break ;
    case '7' :
      $monthName = 'july' ;
      break ;
    case '8' :
      $monthName = 'august' ;
      break ;
    case '9' :
      $monthName = 'september' ;
      break ;
    case '10' :
      $monthName = 'october' ;
      break ;
    case '11' :
      $monthName = 'november' ;
      break ;
    case '12' :
      $monthName = 'december' ;
      break ;
    default :
      $monthName = '' ;
      break ;
    }
    return $monthName ;
}