adding a method to set the root element of the document

ext/nokogiri/xml_document.c

@@ -24,6 +24,24 @@ static VALUE serialize(VALUE self)
   return rb_str;
 }
 
+/*
+ * call-seq:
+ *  root=
+ *
+ * Set the root element on this document
+ */
+static VALUE set_root(VALUE self, VALUE root)
+{
+  xmlDocPtr doc;
+  xmlNodePtr new_root;
+
+  Data_Get_Struct(self, xmlDoc, doc);
+  Data_Get_Struct(root, xmlNode, new_root);
+
+  xmlDocSetRootElement(doc, new_root);
+  return root;
+}
+
 /*
  * call-seq:
  *  root
@@ -107,6 +125,7 @@ void init_xml_document()
   rb_define_singleton_method(klass, "load_external_subsets=", load_external_subsets_set, 1);
 
   rb_define_method(klass, "root", root, 0);
+  rb_define_method(klass, "root=", set_root, 1);
   rb_define_method(klass, "serialize", serialize, 0);
 }
 

ext/nokogiri/xml_node.c

@@ -2,6 +2,9 @@
 
 VALUE Nokogiri_wrap_xml_node(xmlNodePtr root)
 {
+  if(root->_private)
+    return (VALUE)root->_private;
+
   VALUE klass = rb_eval_string("Nokogiri::XML::Node");
   VALUE node = Data_Wrap_Struct(klass, NULL, NULL, root);
   root->_private = (void *)node;
@@ -197,8 +200,7 @@ static VALUE document(VALUE self)
 
 static VALUE new(int argc, VALUE *argv, VALUE klass)
 {
-  VALUE name;
-  VALUE ns;
+  VALUE name, ns;
   xmlNsPtr xml_ns = NULL;
 
   rb_scan_args(argc, argv, "11", &name, &ns);
@@ -209,6 +211,9 @@ static VALUE new(int argc, VALUE *argv, VALUE klass)
   xmlNodePtr node = xmlNewNode(xml_ns, (xmlChar *)StringValuePtr(name));
   VALUE rb_node = Data_Wrap_Struct(klass, NULL, NULL, node);
   node->_private = (void *)rb_node;
+
+  if(rb_block_given_p()) rb_yield(rb_node);
+
   return rb_node;
 }
 

lib/nokogiri.rb

@@ -5,7 +5,6 @@
 require 'nokogiri/native'
 
 module Nokogiri
-
   class << self
     def parse(string, url = nil, encoding = nil, options = 32)
       doc =

lib/nokogiri/hpricot.rb

@@ -1,5 +1,6 @@
 
 require 'nokogiri'
+require 'nokogiri/xml/builder'
 
 module Nokogiri
   module XML
@@ -13,6 +14,11 @@ def search(rule)
   end
 end
 
+def Nokogiri(*args, &block)
+  builder = Nokogiri::XML::Builder.new
+  builder.instance_eval(&block)
+end
+
 
 module Nokogiri
   module Hpricot

lib/nokogiri/xml/builder.rb

@@ -0,0 +1,14 @@
+module Nokogiri
+  module XML
+    class Builder
+      def initialize
+        @doc = Nokogiri::XML::Document.new
+      end
+
+      def method_missing(method, *args, &block)
+        node = Nokogiri::XML::Node.new(method.to_s)
+        node.content = args.first
+      end
+    end
+  end
+end

test/xml/test_document.rb

@@ -47,6 +47,22 @@ def test_new
         assert doc.xml?
         assert_nil doc.root
       end
+
+      def test_set_root
+        doc = nil
+        assert_nothing_raised {
+          doc = Nokogiri::XML::Document.new
+        }
+        assert doc
+        assert doc.xml?
+        assert_nil doc.root
+        node = Nokogiri::XML::Node.new("b") { |n|
+          n.content = 'hello world'
+        }
+        assert_equal('hello world', node.content)
+        doc.root = node
+        assert_equal(node, doc.root)
+      end
     end
   end
 end