test/xml/test_document.rb

# frozen_string_literal: true
require "helper"

require "uri"

module Nokogiri
  module XML
    class TestDocument < Nokogiri::TestCase
      describe Nokogiri::XML::Document do
        URI = if URI.const_defined?(:DEFAULT_PARSER)
          ::URI::DEFAULT_PARSER
        else
          ::URI
        end

        let(:xml) { Nokogiri::XML.parse(File.read(XML_FILE), XML_FILE) }

        def test_default_namespace_inheritance
          doc = Nokogiri::XML::Document.new
          refute(doc.namespace_inheritance)
          doc.namespace_inheritance = true
          assert(doc.namespace_inheritance)
        end

        def test_dtd_with_empty_internal_subset
          doc = Nokogiri::XML(<<~eoxml)
            <?xml version="1.0"?>
            <!DOCTYPE people >
            <people>
            </people>
          eoxml
          assert(doc.root)
        end

        # issue #1005
        def test_strict_parsing_empty_doc_should_raise_exception
          ["", " "].each do |empty_string|
            assert_raises(SyntaxError, "empty string '#{empty_string}' should raise a SyntaxError") do
              Nokogiri::XML(empty_string) { |c| c.strict }
            end
            assert_raises(SyntaxError, "StringIO of '#{empty_string}' should raise a SyntaxError") do
              Nokogiri::XML(StringIO.new(empty_string)) { |c| c.strict }
            end
          end
        end

        # issue #838
        def test_document_with_invalid_prolog
          doc = Nokogiri::XML("<? ?>")
          assert_empty(doc.content)
        end

        # issue #837
        def test_document_with_refentity
          doc = Nokogiri::XML("&amp;")
          assert_equal("", doc.content)
        end

        # issue 1060
        def test_node_ownership_after_dup
          html = "<html><head></head><body><div>replace me</div></body></html>"
          doc = Nokogiri::XML::Document.parse(html)
          dup = doc.dup
          assert_same(dup, dup.at_css("div").document)

          # should not raise an exception
          dup.at_css("div").parse("<div>replaced</div>")
        end

        # issue #835
        def test_manually_adding_reference_entities
          d = Nokogiri::XML::Document.new
          root = Nokogiri::XML::Element.new("bar", d)
          txt = Nokogiri::XML::Text.new("foo", d)
          ent = Nokogiri::XML::EntityReference.new(d, "#8217")
          root << txt
          root << ent
          d << root
          assert_match(/&#8217;/, d.to_html)
        end

        def test_document_with_initial_space
          doc = Nokogiri::XML(" <?xml version='1.0' encoding='utf-8' ?><first \>")
          assert_equal(2, doc.children.size)
        end

        def test_million_laugh_attach
          doc = Nokogiri::XML(<<~EOF)
            <?xml version="1.0"?>
            <!DOCTYPE lolz [
            <!ENTITY lol "lol">
            <!ENTITY lol2 "&lol;&lol;&lol;&lol;&lol;&lol;&lol;&lol;&lol;&lol;">
            <!ENTITY lol3 "&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;">
            <!ENTITY lol4 "&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;">
            <!ENTITY lol5 "&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;">
            <!ENTITY lol6 "&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;">
            <!ENTITY lol7 "&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;">
            <!ENTITY lol8 "&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;">
            <!ENTITY lol9 "&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;">
            ]>
            <lolz>&lol9;</lolz>
          EOF
          assert_not_nil(doc)
        end

        def test_million_laugh_attach_2
          doc = Nokogiri::XML(<<~EOF)
            <?xml version="1.0" encoding="UTF-8"?>
             <!DOCTYPE member [
               <!ENTITY a "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
               <!ENTITY b "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;">
               <!ENTITY c "&d;&d;&d;&d;&d;&d;&d;&d;&d;&d;">
               <!ENTITY d "&e;&e;&e;&e;&e;&e;&e;&e;&e;&e;">
               <!ENTITY e "&f;&f;&f;&f;&f;&f;&f;&f;&f;&f;">
               <!ENTITY f "&g;&g;&g;&g;&g;&g;&g;&g;&g;&g;">
               <!ENTITY g "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
             ]>
             <member>
             &a;
             </member>
          EOF
          assert_not_nil(doc)
        end

        def test_ignore_unknown_namespace
          doc = Nokogiri::XML(<<~eoxml)
            <xml>
              <unknown:foo xmlns='http://hello.com/' />
              <bar />
            </xml>
          eoxml
          if Nokogiri.jruby?
            refute(doc.xpath("//foo").first.namespace) # assert that the namespace is nil
          end
          refute_empty(doc.xpath("//bar"), "bar wasn't found in the document") # bar should be part of the doc
        end

        def test_collect_namespaces
          doc = Nokogiri::XML(<<~eoxml)
            <xml>
              <foo xmlns='hello'>
                <bar xmlns:foo='world' />
              </foo>
            </xml>
          eoxml
          assert_equal({ "xmlns" => "hello", "xmlns:foo" => "world" },
                       doc.collect_namespaces)
        end

        def test_subclass_initialize_modify # testing a segv
          doc = Class.new(Nokogiri::XML::Document) do
            def initialize
              super
              body_node = Nokogiri::XML::Node.new("body", self)
              body_node.content = "stuff"
              self.root = body_node
            end
          end.new
          assert_equal("stuff", doc.root.content)
        end

        def test_create_text_node
          txt = xml.create_text_node("foo")
          assert_instance_of(Nokogiri::XML::Text, txt)
          assert_equal("foo", txt.text)
          assert_equal(xml, txt.document)
        end

        def test_create_text_node_with_block
          xml.create_text_node("foo") do |txt|
            assert_instance_of(Nokogiri::XML::Text, txt)
            assert_equal("foo", txt.text)
            assert_equal(xml, txt.document)
          end
        end

        def test_create_element
          elm = xml.create_element("foo")
          assert_instance_of(Nokogiri::XML::Element, elm)
          assert_equal("foo", elm.name)
          assert_equal(xml, elm.document)
        end

        def test_create_element_with_block
          xml.create_element("foo") do |elm|
            assert_instance_of(Nokogiri::XML::Element, elm)
            assert_equal("foo", elm.name)
            assert_equal(xml, elm.document)
          end
        end

        def test_create_element_with_attributes
          elm = xml.create_element("foo", a: "1")
          assert_instance_of(Nokogiri::XML::Element, elm)
          assert_instance_of(Nokogiri::XML::Attr, elm.attributes["a"])
          assert_equal("1", elm["a"])
        end

        def test_create_element_with_namespace
          elm = xml.create_element("foo", 'xmlns:foo': "http://tenderlovemaking.com")
          assert_equal("http://tenderlovemaking.com", elm.namespaces["xmlns:foo"])
        end

        def test_create_element_with_hyphenated_namespace
          elm = xml.create_element("foo", 'xmlns:SOAP-ENC': "http://tenderlovemaking.com")
          assert_equal("http://tenderlovemaking.com", elm.namespaces["xmlns:SOAP-ENC"])
        end

        def test_create_element_with_invalid_namespace
          if Nokogiri.jruby?
            assert_raises(Java::OrgW3cDom::DOMException) do
              xml.create_element("foo", 'xmlns:SOAP!ENC': "http://tenderlovemaking.com")
            end
          else
            elm = xml.create_element("foo", 'xmlns:SOAP!ENC': "http://tenderlovemaking.com")
            refute_includes(elm.namespaces.keys, "xmlns:SOAP!ENC")
          end
        end

        def test_create_element_with_content
          elm = xml.create_element("foo", "needs more xml/violence")
          assert_equal("needs more xml/violence", elm.content)
        end

        def test_create_cdata
          cdata = xml.create_cdata("abc")
          assert_instance_of(Nokogiri::XML::CDATA, cdata)
          assert_equal("abc", cdata.content)
        end

        def test_create_cdata_with_block
          xml.create_cdata("abc") do |cdata|
            assert_instance_of(Nokogiri::XML::CDATA, cdata)
            assert_equal("abc", cdata.content)
          end
        end

        def test_create_comment
          comment = xml.create_comment("abc")
          assert_instance_of(Nokogiri::XML::Comment, comment)
          assert_equal("abc", comment.content)
        end

        def test_create_comment_with_block
          xml.create_comment("abc") do |comment|
            assert_instance_of(Nokogiri::XML::Comment, comment)
            assert_equal("abc", comment.content)
          end
        end

        def test_pp
          out = StringIO.new(String.new)
          ::PP.pp(xml, out)
          assert_operator(out.string.length, :>, 0)
        end

        def test_create_internal_subset_on_existing_subset
          assert_not_nil(xml.internal_subset)
          assert_raises(RuntimeError) do
            xml.create_internal_subset("staff", nil, "staff.dtd")
          end
        end

        def test_create_internal_subset
          xml = Nokogiri::XML("<root />")
          assert_nil(xml.internal_subset)

          xml.create_internal_subset("name", nil, "staff.dtd")
          ss = xml.internal_subset
          assert_equal("name", ss.name)
          assert_nil(ss.external_id)
          assert_equal("staff.dtd", ss.system_id)
        end

        def test_external_subset
          assert_nil(xml.external_subset)
          xml = Dir.chdir(ASSETS_DIR) do
            Nokogiri::XML.parse(File.read(XML_FILE), XML_FILE) do |cfg|
              cfg.dtdload
            end
          end
          assert(xml.external_subset)
        end

        def test_create_external_subset_fails_with_existing_subset
          assert_nil(xml.external_subset)
          xml = Dir.chdir(ASSETS_DIR) do
            Nokogiri::XML.parse(File.read(XML_FILE), XML_FILE) do |cfg|
              cfg.dtdload
            end
          end
          assert(xml.external_subset)

          assert_raises(RuntimeError) do
            xml.create_external_subset("staff", nil, "staff.dtd")
          end
        end

        def test_create_external_subset
          dtd = xml.create_external_subset("staff", nil, "staff.dtd")
          assert_nil(dtd.external_id)
          assert_equal("staff.dtd", dtd.system_id)
          assert_equal("staff", dtd.name)
          assert_equal(dtd, xml.external_subset)
        end

        def test_version
          assert_equal("1.0", xml.version)
        end

        def test_add_namespace
          assert_raise(NoMethodError) do
            xml.add_namespace("foo", "bar")
          end
        end

        def test_attributes
          assert_raise(NoMethodError) do
            xml.attributes
          end
        end

        def test_namespace
          assert_raise(NoMethodError) do
            xml.namespace
          end
        end

        def test_namespace_definitions
          assert_raise(NoMethodError) do
            xml.namespace_definitions
          end
        end

        def test_line
          assert_raise(NoMethodError) do
            xml.line
          end
        end

        def test_empty_node_converted_to_html_is_not_self_closing
          doc = Nokogiri::XML("<a></a>")
          assert_equal("<a></a>", doc.inner_html)
        end

        def test_fragment
          fragment = xml.fragment
          assert_equal(0, fragment.children.length)
        end

        def test_add_child_fragment_with_single_node
          doc = Nokogiri::XML::Document.new
          fragment = doc.fragment("<hello />")
          doc.add_child(fragment)
          assert_equal("/hello", doc.at("//hello").path)
          assert_equal("hello", doc.root.name)
        end

        def test_add_child_fragment_with_multiple_nodes
          doc = Nokogiri::XML::Document.new
          fragment = doc.fragment("<hello /><goodbye />")
          assert_raises(RuntimeError) do
            doc.add_child(fragment)
          end
        end

        def test_add_child_with_multiple_roots
          assert_raises(RuntimeError) do
            xml << Node.new("foo", xml)
          end
        end

        def test_add_child_with_string
          doc = Nokogiri::XML::Document.new
          doc.add_child("<div>quack!</div>")
          assert_equal(1, doc.root.children.length)
          assert_equal("quack!", doc.root.children.first.content)
        end

        def test_prepend
          doc = Nokogiri::XML("<root>")

          node_set = doc.root.prepend_child("<branch/>")
          assert_equal(%w[branch], node_set.map(&:name))

          branch = doc.at("//branch")

          leaves = %w[leaf1 leaf2 leaf3]
          leaves.each do |name|
            branch.prepend_child("<%s/>" % name)
          end
          assert_equal(leaves.length, branch.children.length)
          assert_equal(leaves.reverse, branch.children.map(&:name))
        end

        def test_prepend_child_fragment_with_single_node
          doc = Nokogiri::XML::Document.new
          fragment = doc.fragment("<hello />")
          doc.prepend_child(fragment)
          assert_equal("/hello", doc.at("//hello").path)
          assert_equal("hello", doc.root.name)
        end

        def test_prepend_child_fragment_with_multiple_nodes
          doc = Nokogiri::XML::Document.new
          fragment = doc.fragment("<hello /><goodbye />")
          assert_raises(RuntimeError) do
            doc.prepend_child(fragment)
          end
        end

        def test_prepend_child_with_multiple_roots
          assert_raises(RuntimeError) do
            xml.prepend_child(Node.new("foo", xml))
          end
        end

        def test_prepend_child_with_string
          doc = Nokogiri::XML::Document.new
          doc.prepend_child("<div>quack!</div>")
          assert_equal(1, doc.root.children.length)
          assert_equal("quack!", doc.root.children.first.content)
        end

        def test_validate
          if Nokogiri.uses_libxml?
            assert_equal(45, xml.validate.length)
          else
            xml = Nokogiri::XML.parse(File.read(XML_FILE), XML_FILE) { |cfg| cfg.dtdvalid }
            assert_equal(40, xml.validate.length)
          end
        end

        def test_validate_no_internal_subset
          doc = Nokogiri::XML("<test/>")
          assert_nil(doc.validate)
        end

        def test_clone
          assert(xml.clone)
        end

        def test_document_should_not_have_default_ns
          doc = Nokogiri::XML::Document.new

          assert_raises(NoMethodError) do
            doc.default_namespace = "http://innernet.com/"
          end

          assert_raises(NoMethodError) do
            doc.add_namespace_definition("foo", "bar")
          end
        end

        def test_parse_handles_nil_gracefully
          @doc = Nokogiri::XML::Document.parse(nil)
          assert_instance_of(Nokogiri::XML::Document, @doc)
        end

        def test_parse_takes_block
          options = nil
          Nokogiri::XML.parse(File.read(XML_FILE), XML_FILE) do |cfg|
            options = cfg
          end
          assert(options)
        end

        def test_parse_yields_parse_options
          options = nil
          Nokogiri::XML.parse(File.read(XML_FILE), XML_FILE) do |cfg|
            options = cfg
            options.nonet.nowarning.dtdattr
          end
          assert(options.nonet?)
          assert(options.nowarning?)
          assert(options.dtdattr?)
        end

        def test_XML_takes_block
          options = nil
          Nokogiri::XML(File.read(XML_FILE), XML_FILE) do |cfg|
            options = cfg
            options.nonet.nowarning.dtdattr
          end
          assert(options.nonet?)
          assert(options.nowarning?)
          assert(options.dtdattr?)
        end

        def test_document_parse_method
          xml = Nokogiri::XML::Document.parse(File.read(XML_FILE))
          # lame hack uses root to avoid comparing DOCTYPE tags which can appear out of order.
          # I should really finish lorax and use that here.
          assert_equal(xml.root.to_s, xml.root.to_s)
        end

        def test_encoding=
          xml.encoding = "UTF-8"
          assert_match("UTF-8", xml.to_xml)

          xml.encoding = "EUC-JP"
          assert_match("EUC-JP", xml.to_xml)
        end

        def test_namespace_should_not_exist
          assert_raises(NoMethodError) do
            xml.namespace
          end
        end

        def test_non_existant_function
          # WTF.  I don't know why this is different between MRI and Jruby
          # They should be the same...  Either way, raising an exception
          # is the correct thing to do.
          exception = RuntimeError

          if !Nokogiri.uses_libxml? || (Nokogiri.uses_libxml? && Nokogiri::VERSION_INFO["libxml"]["platform"] == "jruby")
            exception = Nokogiri::XML::XPath::SyntaxError
          end

          assert_raises(exception) do
            xml.xpath("//name[foo()]")
          end
        end

        def test_xpath_syntax_error
          assert_raises(Nokogiri::XML::XPath::SyntaxError) do
            xml.xpath("\\")
          end
        end

        def test_ancestors
          assert_equal(0, xml.ancestors.length)
        end

        def test_root_node_parent_is_document
          parent = xml.root.parent
          assert_equal(xml, parent)
          assert_instance_of(Nokogiri::XML::Document, parent)
        end

        def test_xmlns_is_automatically_registered
          doc = Nokogiri::XML(<<~eoxml)
            <root xmlns="http://tenderlovemaking.com/">
              <foo>
                bar
              </foo>
            </root>
          eoxml
          assert_equal(1, doc.css("xmlns|foo").length)
          assert_equal(1, doc.css("foo").length)
          assert_equal(0, doc.css("|foo").length)
          assert_equal(1, doc.xpath("//xmlns:foo").length)
          assert_equal(1, doc.search("xmlns|foo").length)
          assert_equal(1, doc.search("//xmlns:foo").length)
          assert(doc.at("xmlns|foo"))
          assert(doc.at("//xmlns:foo"))
          assert(doc.at("foo"))
        end

        def test_xmlns_is_registered_for_nodesets
          doc = Nokogiri::XML(<<~eoxml)
            <root xmlns="http://tenderlovemaking.com/">
              <foo>
                <bar>
                  baz
                </bar>
              </foo>
            </root>
          eoxml
          assert_equal(1, doc.css("xmlns|foo").css("xmlns|bar").length)
          assert_equal(1, doc.css("foo").css("bar").length)
          assert_equal(1, doc.xpath("//xmlns:foo").xpath("./xmlns:bar").length)
          assert_equal(1, doc.search("xmlns|foo").search("xmlns|bar").length)
          assert_equal(1, doc.search("//xmlns:foo").search("./xmlns:bar").length)
        end

        def test_to_xml_with_indent
          doc = Nokogiri::XML("<root><foo><bar/></foo></root>")
          doc = Nokogiri::XML(doc.to_xml(indent: 5))

          assert_indent(5, doc)
        end

        def test_write_xml_to_with_indent
          io = StringIO.new
          doc = Nokogiri::XML("<root><foo><bar/></foo></root>")
          doc.write_xml_to(io, indent: 5)
          io.rewind
          doc = Nokogiri::XML(io.read)
          assert_indent(5, doc)
        end

        unless Nokogiri.uses_libxml?("~> 2.6.0")
          def test_encoding
            xml = Nokogiri::XML(File.read(XML_FILE), XML_FILE, "UTF-8")
            assert_equal("UTF-8", xml.encoding)
          end
        end

        def test_memory_explosion_on_invalid_xml
          doc = Nokogiri::XML("<<<")
          refute_nil(doc)
          refute_empty(doc.errors)
        end

        def test_memory_explosion_on_wrong_formatted_element_following_the_root_element
          doc = Nokogiri::XML("<a/><\n")
          refute_nil(doc)
          refute_empty(doc.errors)
        end

        def test_document_has_errors
          doc = Nokogiri::XML(<<~eoxml)
            <foo><bar></foo>
          eoxml
          assert(doc.errors.length > 0)
          doc.errors.each do |error|
            assert_match(error.message, error.inspect)
            assert_match(error.message, error.to_s)
          end
        end

        def test_strict_document_throws_syntax_error
          assert_raises(Nokogiri::XML::SyntaxError) do
            Nokogiri::XML("<foo><bar></foo>", nil, nil, 0)
          end

          assert_raises(Nokogiri::XML::SyntaxError) do
            Nokogiri::XML("<foo><bar></foo>") do |cfg|
              cfg.strict
            end
          end

          assert_raises(Nokogiri::XML::SyntaxError) do
            Nokogiri::XML(StringIO.new("<foo><bar></foo>")) do |cfg|
              cfg.strict
            end
          end
        end

        def test_XML_function
          xml = Nokogiri::XML(File.read(XML_FILE), XML_FILE)
          assert(xml.xml?)
        end

        def test_url
          assert(xml.url)
          assert_equal(XML_FILE, xml.url)
        end

        def test_document_parent
          xml = Nokogiri::XML(File.read(XML_FILE), XML_FILE)
          assert_raises(NoMethodError) do
            xml.parent
          end
        end

        def test_document_name
          xml = Nokogiri::XML(File.read(XML_FILE), XML_FILE)
          assert_equal("document", xml.name)
        end

        def test_parse_can_take_io
          xml = nil
          File.open(XML_FILE, "rb") do |f|
            xml = Nokogiri::XML(f)
          end
          assert(xml.xml?)
          assert_equal(XML_FILE, xml.url)
          set = xml.search("//employee")
          assert(set.length > 0)
        end

        def test_parsing_empty_io
          doc = Nokogiri::XML.parse(StringIO.new(""))
          refute_nil(doc)
        end

        def test_parse_works_with_an_object_that_responds_to_read
          klass = Class.new do
            def initialize
              @contents = StringIO.new("<div>foo</div>")
            end

            def read(*args)
              @contents.read(*args)
            end
          end

          doc = Nokogiri::XML.parse(klass.new)
          assert_equal("foo", doc.at_css("div").content)
        end

        def test_parse_works_with_an_object_that_responds_to_path
          xml = String.new("<root><sub>hello</sub></root>")
          def xml.path
            "/i/should/be/the/document/url"
          end

          doc = Nokogiri::XML.parse(xml)

          assert_equal("/i/should/be/the/document/url", doc.url)
        end

        # issue #1821, #2110
        def test_parse_can_take_pathnames
          assert(File.size(XML_ATOM_FILE) > 4096) # file must be big enough to trip the read callback more than once

          doc = Nokogiri::XML.parse(Pathname.new(XML_ATOM_FILE))

          # an arbitrary assertion on the structure of the document
          assert_equal(20, doc.xpath("/xmlns:feed/xmlns:entry/xmlns:author",
            "xmlns" => "http://www.w3.org/2005/Atom").length)
          assert_equal(XML_ATOM_FILE, doc.url)
        end

        def test_search_on_empty_documents
          doc = Nokogiri::XML::Document.new
          ns = doc.search("//foo")
          assert_equal(0, ns.length)

          ns = doc.css("foo")
          assert_equal(0, ns.length)

          ns = doc.xpath("//foo")
          assert_equal(0, ns.length)
        end

        def test_document_search_with_multiple_queries
          xml = '<document>
                 <thing>
                   <div class="title">important thing</div>
                 </thing>
                 <thing>
                   <div class="content">stuff</div>
                 </thing>
                 <thing>
                   <p class="blah">more stuff</div>
                 </thing>
               </document>'
          document = Nokogiri::XML(xml)
          assert_kind_of(Nokogiri::XML::Document, document)

          assert_equal(3, document.xpath(".//div", ".//p").length)
          assert_equal(3, document.css(".title", ".content", "p").length)
          assert_equal(3, document.search(".//div", "p.blah").length)
        end

        def test_bad_xpath_raises_syntax_error
          assert_raises(XML::XPath::SyntaxError) do
            xml.xpath("\\")
          end
        end

        def test_find_with_namespace
          doc = Nokogiri::XML.parse(<<~eoxml)
            <x xmlns:tenderlove='http://tenderlovemaking.com/'>
              <tenderlove:foo awesome='true'>snuggles!</tenderlove:foo>
            </x>
          eoxml

          ctx = Nokogiri::XML::XPathContext.new(doc)
          ctx.register_ns("tenderlove", "http://tenderlovemaking.com/")
          set = ctx.evaluate("//tenderlove:foo")
          assert_equal(1, set.length)
          assert_equal("foo", set.first.name)

          # It looks like only the URI is important:
          ctx = Nokogiri::XML::XPathContext.new(doc)
          ctx.register_ns("america", "http://tenderlovemaking.com/")
          set = ctx.evaluate("//america:foo")
          assert_equal(1, set.length)
          assert_equal("foo", set.first.name)

          # Its so important that a missing slash will cause it to return nothing
          ctx = Nokogiri::XML::XPathContext.new(doc)
          ctx.register_ns("america", "http://tenderlovemaking.com")
          set = ctx.evaluate("//america:foo")
          assert_equal(0, set.length)
        end

        def test_xml?
          assert(xml.xml?)
        end

        def test_document
          assert(xml.document)
        end

        def test_singleton_methods
          assert(node_set = xml.search("//name"))
          assert(node_set.length > 0)
          node = node_set.first
          def node.test
            "test"
          end
          assert(node_set = xml.search("//name"))
          assert_equal("test", node_set.first.test)
        end

        def test_multiple_search
          assert(node_set = xml.search("//employee", "//name"))
          employees = xml.search("//employee")
          names = xml.search("//name")
          assert_equal(employees.length + names.length, node_set.length)
        end

        def test_node_set_index
          assert(node_set = xml.search("//employee"))

          assert_equal(5, node_set.length)
          assert(node_set[4])
          assert_nil(node_set[5])
        end

        def test_search
          assert(node_set = xml.search("//employee"))

          assert_equal(5, node_set.length)

          node_set.each do |node|
            assert_equal("employee", node.name)
          end
        end

        def test_dump
          assert(xml.serialize)
          assert(xml.to_xml)
        end

        def test_dup
          dup = xml.dup
          assert_instance_of(Nokogiri::XML::Document, dup)
          assert(dup.xml?, "duplicate should be xml")
        end

        def test_new
          doc = nil
          doc = Nokogiri::XML::Document.new
          assert(doc)
          assert(doc.xml?)
          assert_nil(doc.root)
        end

        def test_remove_namespaces
          doc = Nokogiri::XML(<<~EOX)
            <root xmlns:a="http://a.flavorjon.es/" xmlns:b="http://b.flavorjon.es/">
              <a:foo>hello from a</a:foo>
              <b:foo>hello from b</b:foo>
              <container xmlns:c="http://c.flavorjon.es/">
                <c:foo c:attr='attr-value'>hello from c</c:foo>
              </container>
            </root>
          EOX

          namespaces = doc.root.namespaces

          # assert on setup
          assert_equal(2, doc.root.namespaces.length)
          assert_equal(3, doc.at_xpath("//container").namespaces.length)
          assert_equal(0, doc.xpath("//foo").length)
          assert_equal(1, doc.xpath("//a:foo").length)
          assert_equal(1, doc.xpath("//a:foo").length)
          assert_equal(1, doc.xpath("//x:foo", "x" => "http://c.flavorjon.es/").length)
          assert_match(/foo c:attr/, doc.to_xml)
          doc.at_xpath("//x:foo", "x" => "http://c.flavorjon.es/").tap do |node|
            assert_nil(node["attr"])
            assert_equal("attr-value", node["c:attr"])
            assert_nil(node.attribute_with_ns("attr", nil))
            assert_equal("attr-value", node.attribute_with_ns("attr", "http://c.flavorjon.es/").value)
            assert_equal("attr-value", node.attributes["attr"].value)
          end

          doc.remove_namespaces!

          assert_equal(0, doc.root.namespaces.length)
          assert_equal(0, doc.at_xpath("//container").namespaces.length)
          assert_equal(3, doc.xpath("//foo").length)
          assert_equal(0, doc.xpath("//a:foo", namespaces).length)
          assert_equal(0, doc.xpath("//a:foo", namespaces).length)
          assert_equal(0, doc.xpath("//x:foo", "x" => "http://c.flavorjon.es/").length)
          assert_match(/foo attr/, doc.to_xml)
          doc.at_xpath("//container/foo").tap do |node|
            assert_equal("attr-value", node["attr"])
            assert_nil(node["c:attr"])
            assert_equal("attr-value", node.attribute_with_ns("attr", nil).value)
            assert_nil(node.attribute_with_ns("attr", "http://c.flavorjon.es/"))
            assert_equal("attr-value", node.attributes["attr"].value) # doesn't change!
          end
        end

        # issue #785
        def test_attribute_decoration
          decorator = Module.new do
            def test_method
            end
          end

          util_decorate(xml, decorator)

          assert(xml.search("//@street").first.respond_to?(:test_method))
        end

        def test_subset_is_decorated
          x = Module.new do
            def awesome!
            end
          end
          util_decorate(xml, x)

          assert(xml.respond_to?(:awesome!))
          assert(node_set = xml.search("//staff"))
          assert(node_set.respond_to?(:awesome!))
          assert(subset = node_set.search(".//employee"))
          assert(subset.respond_to?(:awesome!))
          assert(sub_subset = node_set.search(".//name"))
          assert(sub_subset.respond_to?(:awesome!))
        end

        def test_decorator_is_applied
          x = Module.new do
            def awesome!
            end
          end
          util_decorate(xml, x)

          assert(xml.respond_to?(:awesome!))
          assert(node_set = xml.search("//employee"))
          assert(node_set.respond_to?(:awesome!))
          node_set.each do |node|
            assert(node.respond_to?(:awesome!), node.class)
          end
          assert(xml.root.respond_to?(:awesome!))
          assert(xml.children.respond_to?(:awesome!))
        end

        def test_can_be_closed
          f = File.open(XML_FILE)
          Nokogiri::XML(f)
          f.close
        end

        describe "JRuby-only methods" do
          describe "Document.wrap" do
            if Nokogiri.jruby?
              let(:java_doc) do
                require "java"
                factory = javax.xml.parsers.DocumentBuilderFactory.newInstance
                builder = factory.newDocumentBuilder
                document = builder.newDocument
                root = document.createElement("foo")
                document.appendChild(root)
                document
              end

              it "wraps a Java document" do
                rb_doc = Nokogiri::XML::Document.wrap(java_doc)
                assert_kind_of(Nokogiri::XML::Document, rb_doc)
                assert_equal("foo", rb_doc.root.name)
              end

              it "shares the same data structure as shown when modified via Java interop" do
                rb_doc = Nokogiri::XML::Document.wrap(java_doc)
                assert_equal(0, rb_doc.root.children.length)

                java_doc.getFirstChild.appendChild(java_doc.createElement("bar"))
                assert_equal(1, rb_doc.root.children.length)
              end

              it "shares the same data structure as shown when modified via Nokogiri" do
                rb_doc = Nokogiri::XML::Document.wrap(java_doc)
                assert_equal(0, java_doc.getFirstChild.getChildNodes.getLength)

                rb_doc.root.add_child("<bar />")
                assert_equal(1, java_doc.getFirstChild.getChildNodes.getLength)
              end
            else
              it "does not have the method" do
                refute_respond_to(Nokogiri::XML::Document, :wrap)
              end
            end
          end

          describe "Document#to_java" do
            if Nokogiri.jruby?
              let(:rb_doc) do
                Nokogiri::XML::Document.parse("<foo xmlns='hello'><bar xmlns:foo='world' /></foo>")
              end

              it "returns the underlying java object" do
                java_doc = rb_doc.to_java
                assert_kind_of(org.w3c.dom.Document, java_doc)
                assert_equal("foo", java_doc.getDocumentElement.getTagName)
              end

              it "shares the same data structure as shown when modified via Nokogiri" do
                java_doc = rb_doc.to_java
                assert_equal(1, java_doc.getFirstChild.getChildNodes.getLength)

                rb_doc.root.add_child("<baz />")
                assert_equal(2, java_doc.getFirstChild.getChildNodes.getLength)
              end

              it "shares the same data structure as shown when modified via Java interop" do
                java_doc = rb_doc.to_java
                assert_equal(1, rb_doc.root.children.length)

                java_doc.getFirstChild.appendChild(java_doc.createElement("baz"))
                assert_equal(2, rb_doc.root.children.length)
              end
            else
              it "does not have the method" do
                refute_respond_to(Nokogiri::XML::Document.new, :to_java)
              end
            end
          end
        end

        describe "XML::Document.parse" do
          # establish baseline behavior for HTML document behavior in
          # https://github.com/sparklemotion/nokogiri/issues/2130
          # (see similar tests in test/html/test_document.rb)
          let(:xml_strict) do
            Nokogiri::XML::ParseOptions.new(Nokogiri::XML::ParseOptions::DEFAULT_XML).norecover
          end

          it "sets the test up correctly" do
            assert(xml_strict.strict?)
          end

          describe "read memory" do
            let(:input) { "<html><body><div" }

            describe "strict parsing" do
              let(:parse_options) { xml_strict }

              it "raises exception on parse error" do
                assert_raises Nokogiri::SyntaxError do
                  Nokogiri::XML.parse(input, nil, nil, parse_options)
                end
              end
            end

            describe "default options" do
              it "does not raise exception on parse error" do
                doc = Nokogiri::XML.parse(input)
                assert_operator(doc.errors.length, :>, 0)
              end
            end
          end

          describe "read io" do
            let(:input) { StringIO.new("<html><body><div") }

            describe "strict parsing" do
              let(:parse_options) { xml_strict }

              it "raises exception on parse error" do
                assert_raises Nokogiri::SyntaxError do
                  Nokogiri::XML.parse(input, nil, nil, parse_options)
                end
              end
            end

            describe "default options" do
              it "does not raise exception on parse error" do
                doc = Nokogiri::XML.parse(input)
                assert_operator(doc.errors.length, :>, 0)
              end
            end
          end
        end

        describe "subclassing" do
          let(:klass) do
            Class.new(Nokogiri::XML::Document) do
              attr_accessor :initialized_with, :initialized_count

              def initialize(*args)
                super
                @initialized_with = args
                @initialized_count ||= 0
                @initialized_count += 1
              end
            end
          end

          describe ".new" do
            it "returns an instance of the expected class" do
              doc = klass.new
              assert_instance_of(klass, doc)
            end

            it "calls #initialize exactly once" do
              doc = klass.new
              assert_equal(1, doc.initialized_count)
            end

            it "passes arguments to #initialize" do
              doc = klass.new("1.0", 1)
              assert_equal ["1.0", 1], doc.initialized_with
            end
          end

          it "#dup returns the expected class" do
            doc = klass.new.dup
            assert_instance_of(klass, doc)
          end

          describe ".parse" do
            it "returns an instance of the expected class" do
              doc = klass.parse(File.read(XML_FILE))
              assert_instance_of(klass, doc)
            end

            it "calls #initialize exactly once" do
              doc = klass.parse(File.read(XML_FILE))
              assert_equal(1, doc.initialized_count)
            end

            it "parses the doc" do
              doc = klass.parse(File.read(XML_FILE))
              assert_equal xml.root.to_s, doc.root.to_s
            end
          end
        end

        describe "#root=" do
          it "assigns a root node" do
            doc = Nokogiri::XML::Document.new
            node = doc.create_element("div")
            assert_nil(doc.root)

            doc.root = node

            assert_equal(node, doc.root)
          end

          it "allows removing the root node by setting to nil" do
            assert_kind_of(Nokogiri::XML::Node, xml.root)
            assert_nil(xml.root = nil)
            assert_nil(xml.root)
          end

          it "supports moving nodes across documents" do
            source = Nokogiri::XML("<root>foo</root>")
            target = Nokogiri::XML::Document.new
            assert_nil(target.root)
            target.root = source.root
            assert_equal("foo", target.root.content)
          end

          it "doesn't leak the replaced node" do
            skip("only run if NOKOGIRI_GC is set") unless ENV["NOKOGIRI_GC"]
            doc = Nokogiri::XML("<root>test</root>")
            doc2 = Nokogiri::XML("<root>#{"x" * 5000000}</root>")
            doc2.root = doc.root
          end

          it "raises an exception if passed something besides a Node" do
            doc = Nokogiri::XML::Document.parse(<<~EOF)
              <root>
                <div>one</div>
                <div>two</div>
                <div>three</div>
              </root>
            EOF
            node_set = doc.css("div")
            assert_kind_of(Nokogiri::XML::NodeSet, node_set)
            e = assert_raises(ArgumentError) do
              doc.root = node_set
            end
            assert_equal("expected Nokogiri::XML::Node but received Nokogiri::XML::NodeSet", e.message)
          end
        end

        describe "#path" do
          it "should return '/'" do
            xml = <<~EOF
              <root></root>
            EOF

            doc = Nokogiri::XML::Document.parse(xml)
            assert_equal("/", doc.path)
            assert_equal(doc, doc.at_xpath(doc.path)) # make sure we can round-trip
          end
        end
      end
    end
  end
end