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diff --git a/actionview/lib/action_view/testing/assertions/dom.rb b/actionview/lib/action_view/testing/assertions/dom.rb
new file mode 100644
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+++ b/actionview/lib/action_view/testing/assertions/dom.rb
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+module ActionView
+  module Assertions
+    module DomAssertions
+      # \Test two HTML strings for equivalency (e.g., equal even when attributes are in another order)
+      #
+      #   # assert that the referenced method generates the appropriate HTML string
+      #   assert_dom_equal '<a href="http://www.example.com">Apples</a>', link_to("Apples", "http://www.example.com")
+      def assert_dom_equal(expected, actual, message = nil)
+        expected_dom, actual_dom = doms_from_strings(expected, actual)
+        message ||= "Expected: #{expected_dom}\nActual: #{actual_dom}"
+        assert compare_doms(expected_dom, actual_dom), message
+      end
+
+      # The negated form of +assert_dom_equal+.
+      #
+      #   # assert that the referenced method does not generate the specified HTML string
+      #   assert_dom_not_equal '<a href="http://www.example.com">Apples</a>', link_to("Oranges", "http://www.example.com")
+      def assert_dom_not_equal(expected, actual, message = nil)
+        expected_dom, actual_dom = doms_from_strings(expected, actual)
+        message ||= "Expected: #{expected_dom}\nActual: #{actual_dom}"
+        assert_not compare_doms(expected_dom, actual_dom), message
+      end
+
+      protected
+        # +doms_from_strings+ creates a Loofah::HTML::DocumentFragment for every string in strings
+        def doms_from_strings(*strings)
+          strings.map { |str| Loofah.fragment(str) }
+        end
+
+        # +compare_doms+ takes two doms loops over all their children and compares each child via +equal_children?+
+        def compare_doms(expected, actual)
+          expected.children.each_with_index do |child, i|
+            return false unless equal_children?(child, actual.children[i])
+          end
+          true
+        end
+
+        # +equal_children?+ compares children according to their type
+        # Determines further comparison via said type
+        # i.e. element node children with equal names has their attributes compared using +attributes_are_equal?+
+        def equal_children?(child, other_child)
+          return false unless child.type == other_child.type
+
+          case child.type
+          when Nokogiri::XML::Node::ELEMENT_NODE
+            child.name == other_child.name && attributes_are_equal?(child, other_child)
+          else
+            child.to_s == other_child.to_s
+          end
+        end
+
+        # +attributes_are_equal?+ sorts elements attributes by name and compares
+        # each attribute by calling +equal_attribute?+
+        # If those are +true+ the attributes are considered equal
+        def attributes_are_equal?(element, other_element)
+          first_nodes = element.attribute_nodes.sort_by { |a| a.name }
+          other_nodes = other_element.attribute_nodes.sort_by { |a| a.name }
+
+          return false unless first_nodes.size == other_nodes.size
+          first_nodes.each_with_index do |attr, i|
+            return false unless equal_attribute?(attr, other_nodes[i])
+          end
+          true
+        end
+
+        # +equal_attribute?+ compares attributes by their name and value
+        def equal_attribute?(attr, other_attr)
+          attr.name == other_attr.name && attr.value == other_attr.value
+        end
+    end
+  end
+end