gistfile1.txt

diff --git a/sky/engine/core/dom/ContainerNode.cpp b/sky/engine/core/dom/ContainerNode.cpp
index 97f3708..add9acc 100644
--- a/sky/engine/core/dom/ContainerNode.cpp
+++ b/sky/engine/core/dom/ContainerNode.cpp
@@ -921,6 +921,60 @@ PassRefPtr<Node> ContainerNode::prependChild(PassRefPtr<Node> node, ExceptionSta
     return insertBefore(node, m_firstChild, es);
 }
 
+void ContainerNode::appendSubtree(Vector<int> commands, Vector<String> data)
+{
+    RefPtr<ContainerNode> protect(this);
+
+    Vector<RefPtr<Node>, 10> parents;
+    parents.append(this);
+    RefPtr<Node> currentNode;
+    Vector<Attribute> currentAttributes;
+
+    auto dataIterator = data.begin();
+
+    int minCommand = 0;
+    for (int command : commands) {
+        if (command < minCommand)
+            return;
+        switch(command) {
+        case 0:
+            if (dataIterator == data.end())
+                return;
+            currentNode = document().createElement(*dataIterator++);
+            minCommand = 1;
+            break;
+        case 1:
+            if (dataIterator == data.end())
+                return;
+            String name = *dataIterator++;
+            if (dataIterator == data.end())
+                return;
+            String value = *dataIterator++;
+            currentAttributes.append(QualifiedName(name), value);
+            break;
+        case 2:
+            currentNode->parserSetAttributes(currentAttributes);
+            minCommand = 3;
+            break;
+        case 3:
+            currentAttributes.resize(0);
+            parents.last()->parserAppendChild(currentNode);
+            parents.append(currentNode);
+            minCommand = 0;
+            break;
+        case 4:
+            currentAttributes.resize(0);
+            parents.removeLast();
+            if (parents.isEmpty())
+                return;
+            minCommand = 0;
+            break;
+        default:
+            return;
+        }
+    }
+}
+
 PassRefPtr<Node> ContainerNode::setChild(PassRefPtr<Node> node, ExceptionState& es)
 {
     RefPtr<ContainerNode> protect(this);
diff --git a/sky/engine/core/dom/ContainerNode.h b/sky/engine/core/dom/ContainerNode.h
index bc9108d..fdc9ba0 100644
--- a/sky/engine/core/dom/ContainerNode.h
+++ b/sky/engine/core/dom/ContainerNode.h
@@ -62,6 +62,8 @@ public:
     void prepend(Vector<RefPtr<Node>>& nodes, ExceptionState&);
     PassRefPtr<Node> prependChild(PassRefPtr<Node> node, ExceptionState&);
 
+    void appendSubtree(Vector<int> commands, Vector<String> data);
+
     void removeChildren();
     PassRefPtr<Node> setChild(PassRefPtr<Node> node, ExceptionState&);
     void setChildren(Vector<RefPtr<Node>>& nodes, ExceptionState&);
diff --git a/sky/engine/core/dom/ParentNode.idl b/sky/engine/core/dom/ParentNode.idl
index 519ca50..d8b0573 100644
--- a/sky/engine/core/dom/ParentNode.idl
+++ b/sky/engine/core/dom/ParentNode.idl
@@ -18,6 +18,8 @@
   [RaisesException] void prepend(sequence<Node> nodes);
   [RaisesException] Node prependChild(Node nodes);
 
+  void appendSubtree(sequence<int> commands, sequence<DOMString> data);
+
   void removeChildren();
   [RaisesException] Node setChild(Node node);
   [RaisesException] void setChildren(sequence<Node> nodes);