code: function handleGroup(self, group, width, maxColumns) {
    if (group.length === 0) {
      return;
    }
    var minRows = Math.ceil(group.length / maxColumns);
    for (var row = 0; row < minRows; row++) {
      for (var col = 0; col < maxColumns; col++) {
        var idx = row * maxColumns + col;
        if (idx >= group.length) {
          break;
        }
        var item = group[idx];
        self._writeToOutput(item);
        if (col < maxColumns - 1) {
          for (var s = 0; s < width - item.length; s++) {
            self._writeToOutput(' ');
          }
        }
      }
      self._writeToOutput('\r\n');
    }
    self._writeToOutput('\r\n');
  }
docs: this = Interface instance