# File lib/html5/treebuilders/simpletree.rb, line 56
        def insertBefore node, refNode
          index = childNodes.index(refNode)
          if node.kind_of?(TextNode) && index > 0 && childNodes[index-1].kind_of?(TextNode)
            childNodes[index-1].value += node.value
          else
            childNodes.insert index, node
          end
        end