(function () {

  'use strict';

  function getLastDayOfQuarter(date) {

    var year = date.getFullYear();

    return [[3, 31], [6, 30], [9, 30], [12, 31]]

      .map(function (dates) {

        return new Date(year, dates[0] - 1, dates[1]);

      })

      .filter(function (endDate) {

        return date <= endDate;

      })[0];

  }

  var endOfQuarter = getLastDayOfQuarter(new Date());

  console.log(endOfQuarter.toDateString());

})();