diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index 91814bbcb49d92f98f7ba3c4a9c58aad0f43d7e0..9a5fa719a86f64818843792928508d87bb869ae6 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -150,10 +150,6 @@ def initialize(env = {})
       self.session_options = TestSession::DEFAULT_OPTIONS.merge(:id => SecureRandom.hex(16))
     end
 
-    class Result < ::Array #:nodoc:
-      def to_s() join '/' end
-    end
-
     def assign_parameters(routes, controller_path, action, parameters = {})
       parameters = parameters.symbolize_keys.merge(:controller => controller_path, :action => action)
       extra_keys = routes.extra_keys(parameters)
@@ -171,7 +167,7 @@ def assign_parameters(routes, controller_path, action, parameters = {})
           non_path_parameters[key] = value
         else
           if value.is_a?(Array)
-            value = Result.new(value.map(&:to_param))
+            value = value.map(&:to_param)
           else
             value = value.to_param
           end
diff --git a/actionpack/test/controller/test_case_test.rb b/actionpack/test/controller/test_case_test.rb
index 49137946fec69797af6644bac8e6d36f92805a59..6fccfea0d0c69e2abf4e52c6ae94e6f47aab2d37 100644
--- a/actionpack/test/controller/test_case_test.rb
+++ b/actionpack/test/controller/test_case_test.rb
@@ -635,7 +635,7 @@ def test_array_path_parameter_handled_properly
 
       get :test_params, :path => ['hello', 'world']
       assert_equal ['hello', 'world'], @request.path_parameters['path']
-      assert_equal 'hello/world', @request.path_parameters['path'].to_s
+      assert_equal 'hello/world', @request.path_parameters['path'].to_param
     end
   end
 
@@ -913,4 +913,4 @@ def test_controller_name
     get :index
     assert_equal 'anonymous', @response.body
   end
-end
\ No newline at end of file
+end