code: function(start, end, direction) {
        var current = (start = startOfLine(start)), before = start && startOfLine(start.previousSibling);
        if (!isBR(end)) end = endOfLine(end, this.container);
        this.addDirtyNode(start);
  
        do {
          var next = endOfLine(current, this.container);
          if (current) this.highlight(before, next, true);
          this.indentLineAfter(current, direction);
          before = current;
          current = next;
        } while (current != end);
        select.setCursorPos(this.container, {node: start, offset: 0}, {node: end, offset: 0});
      }
docs: Indent all lines whose start falls inside of the current selection.