class Nokogiri::XML::Node

def parse(string_or_io, options = nil)
  ##
  # When the current node is unparented and not an element node, use the
  # document as the parsing context instead. Otherwise, the in-context
  # parser cannot find an element or a document node.
  # Document Fragments are also not usable by the in-context parser.
  if !element? && !document? && (!parent || parent.fragment?)
    return document.parse(string_or_io, options)
  end
  options ||= (document.html? ? ParseOptions::DEFAULT_HTML : ParseOptions::DEFAULT_XML)
  options = Nokogiri::XML::ParseOptions.new(options) if Integer === options
  yield options if block_given?
  contents = if string_or_io.respond_to?(:read)
    string_or_io.read
  else
    string_or_io
  end
  return Nokogiri::XML::NodeSet.new(document) if contents.empty?
  error_count = document.errors.length
  node_set = in_context(contents, options.to_i)
  if document.errors.length > error_count
    raise document.errors[error_count] unless options.recover?
    if node_set.empty?
      # libxml2 < 2.13 does not obey the +recover+ option after encountering errors during
      # +in_context+ parsing, and so this horrible hack is here to try to emulate recovery
      # behavior.
      #
      # (Note that HTML4 fragment parsing seems to have been fixed in abd74186, and XML
      # fragment parsing is fixed in 1c106edf. Both are in 2.13.)
      #
      # Unfortunately, this means we're no longer parsing "in context" and so namespaces that
      # would have been inherited from the context node won't be handled correctly. This hack
      # was written in 2010, and I regret it, because it's silently degrading functionality in
      # a way that's not easily prevented (or even detected).
      #
      # I think preferable behavior would be to either:
      #
      # a. add an error noting that we "fell back" and pointing the user to turning off the
      #    +recover+ option
      # b. don't recover, but raise a sensible exception
      #
      # For context and background:
      # - https://github.com/sparklemotion/nokogiri/issues/313
      # - https://github.com/sparklemotion/nokogiri/issues/2092
      fragment = document.related_class("DocumentFragment").parse(contents)
      node_set = fragment.children
    end
  end
  node_set
end