code: function(year) {
      var self = this;
      var date = this.easterSunday(year);
      var dayOfWeek = null;
  
      function resolveFriday() {
        if (dayOfWeek === self.FRIDAY) {
          return date;
        } else {
          date = self.subtractDays(date, 1);
          dayOfWeek = self.getDayOfWeek(date);
          return resolveFriday();
        }
      }
  
      return resolveFriday();
    }
docs: Determines the date of Good Friday.
  Friday before Easter Sunday
  @param {number} year
  @return {Date}