code: function setValue(d1, d2) {
              if (compareDates(d1, d2) === 1) {
                  throw new RangeError();
              }
  
              if (compareDates(d1, this.minDateField.date) !== 0 ||
                  compareDates(d2, this.maxDateField.date) !== 0   )
              {
                  var prev = this.getValue();
                  this.minDateField.setValue(d1);
                  this.maxDateField.setValue(d2);
  
                  this.getCalendar().monthDays.retagModel();
  
                  this.fire("dateRangeSelected", [this, prev]);
                  if (this.dateRangeSelected !== undefined) {
                      this.dateRangeSelected(prev);
                  }
              }
          }
docs: Set the given date range.
  @param {Date} d1 a minimal possible date
  @param {Date} d2 a maximal possible date
  @method setValue