1 files changed, 28 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/assertions/assert_dom.rb b/actionpack/lib/action_controller/assertions/assert_dom.rb
new file mode 100644
index 0000000000..a765dff2cc
--- /dev/null
+++ b/actionpack/lib/action_controller/assertions/assert_dom.rb
@@ -0,0 +1,28 @@
+require 'test/unit'
+require 'test/unit/assertions'
+
+module ActionController
+  module Assertions
+    module DomAssertions
+      # test 2 html strings to be equivalent, i.e. identical up to reordering of attributes
+      def assert_dom_equal(expected, actual, message="")
+        clean_backtrace do
+          expected_dom = HTML::Document.new(expected).root
+          actual_dom = HTML::Document.new(actual).root
+          full_message = build_message(message, "<?> expected to be == to\n<?>.", expected_dom.to_s, actual_dom.to_s)
+          assert_block(full_message) { expected_dom == actual_dom }
+        end
+      end
+      
+      # negated form of +assert_dom_equivalent+
+      def assert_dom_not_equal(expected, actual, message="")
+        clean_backtrace do
+          expected_dom = HTML::Document.new(expected).root
+          actual_dom   = HTML::Document.new(actual).root
+          full_message = build_message(message, "<?> expected to be != to\n<?>.", expected_dom.to_s, actual_dom.to_s)
+          assert_block(full_message) { expected_dom != actual_dom }
+        end
+      end
+    end
+  end
+end
+\ No newline at end of file