class Nokogiri::HTML5::DocumentFragment

def self.parse(tags, encoding = nil, options = {})

Parse a document fragment from +tags+, returning a Nodeset. 
def self.parse(tags, encoding = nil, options = {})
  doc = HTML5::Document.new
  tags = HTML5.read_and_encode(tags, encoding)
  doc.encoding = 'UTF-8'
  new(doc, tags, nil, options)
end

def initialize(doc, tags = nil, ctx = nil, options = {})

Create a document fragment. 
def initialize(doc, tags = nil, ctx = nil, options = {})
  return self unless tags
  if ctx
    raise Argument.new("Fragment parsing with context not supported")
  else
    tags = Nokogiri::HTML5.read_and_encode(tags, nil)
    # Copied from Nokogiri's document_fragment.rb and labled "a horrible
    # hack."
    if tags.strip =~ /^<body/i
      path = "/html/body"
    else
      path = "/html/body/node()"
    end
    # Add 2 for <html> and <body>.
    max_depth = (options[:max_tree_depth] || Nokogumbo::DEFAULT_MAX_TREE_DEPTH) + 2
    options = options.dup
    options[:max_tree_depth] = max_depth
    temp_doc = HTML5.parse("<!DOCTYPE html><html><body>#{tags}", options)
    temp_doc.xpath(path).each { |child| child.parent = self }
  self.errors = temp_doc.errors
  end
end

def serialize(options = {}, &block) 

def serialize(options = {}, &block)
  # Bypass XML::Document.serialize which doesn't support options even
  # though XML::Node.serialize does!
  XML::Node.instance_method(:serialize).bind(self).call(options, &block)
end