require 'nokogiri'
builder = Nokogiri::XML::Builder.new do |xml|
    xml.mods("xmlns"=>"http://www.loc.gov/mods/v3") {
         xml.name(:type=>"personal") {
           xml.namePart()
         }
       }
end
ng_xml = builder.doc
new_doc = Nokogiri::XML(ng_xml.to_s)
xpath = '//oxns:name[@type="personal"]'
namespaces = {'oxns' => "http://www.loc.gov/mods/v3"}
original_result = ng_xml.xpath(xpath, namespaces)
clone_result = new_doc.xpath(xpath, namespaces)
puts "clone length #{clone_result.length}"
puts "original length #{original_result.length}"
puts clone_result.length == original_result.length ? "Success" : "Failure"