Get the bounds of a day

day_bounds.js

function dayBounds(date) {
  var t1 = new Date(date.getTime());
  t1.setHours(0, 0, 0, 0);

  var t2 = new Date(date.getTime());
  t2.setHours(23, 59, 59, 999);

  return [t1, t2];
}

Date.prototype.dayBounds = function() {
  return dayBounds(this);
};

same_day.js

function sameDay(date1, date2) {
  return date1.getFullYear() == date2.getFullYear() &&
    date1.getMonth() == date2.getMonth() &&
    date1.getDate() == date2.getDate();
}

Date.prototype.sameDay = function(otherDate) {
  return sameDay(this, otherDate);
};