src/date-util.js
function daysInMonth(date) {
  var d = new Date(date.getTime());
  d.setMonth(d.getMonth() + 1);
  d.setDate(0);

  return d.getDate();
}
function daysInMonth(date) {
  var d = new Date(date.getTime());
  d.setMonth(d.getMonth() + 1);
  d.setDate(0);

  return d.getDate();
}
function daysInMonth ( date ) { var d = new Date ( date . getTime ( ) ) ; d . setMonth ( d . getMonth ( ) + 1 ) ; d . setDate ( 0 ) ; return d . getDate ( ) ; }
Helper function for returning the number of days in a month
Helper function for returning the number of days in a month