1 files changed, 14 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index e6695ffc90..98ed1c2382 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -3,6 +3,9 @@ require 'active_support/core_ext/object/to_query'
 require 'active_support/core_ext/module/anonymous'
 require 'active_support/core_ext/hash/keys'
 
+require 'loofah'
+require 'rails-dom-testing'
+
 module ActionController
   module TemplateAssertions
     extend ActiveSupport::Concern
@@ -432,6 +435,7 @@ module ActionController
       extend ActiveSupport::Concern
       include ActionDispatch::TestProcess
       include ActiveSupport::Testing::ConstantLookup
+      include Rails::Dom::Testing::Assertions
 
       attr_reader :response, :request
 
@@ -678,6 +682,16 @@ module ActionController
       end
 
       private
+
+      def document_root_element
+        @html_document ||= if @response.content_type =~ /xml$/
+          Loofah.xml_document(@response.body)
+        else
+          Loofah.document(@response.body)
+        end.root
+      end
+
+
       def check_required_ivars
         # Sanity check for required instance variables so we can give an
         # understandable error message.