PARAMETERS_KEY is only used in the request, so move the constant there

actionpack/lib/action_dispatch/http/parameters.rb

@@ -4,6 +4,8 @@
 module ActionDispatch
   module Http
     module Parameters
+      PARAMETERS_KEY = 'action_dispatch.request.path_parameters'
+
       def initialize(env)
         super
         @symbolized_path_params = nil
@@ -25,7 +27,7 @@ def parameters
 
       def path_parameters=(parameters) #:nodoc:
         @env.delete('action_dispatch.request.parameters')
-        @env[Routing::RouteSet::PARAMETERS_KEY] = parameters
+        @env[PARAMETERS_KEY] = parameters
       end
 
       # The same as <tt>path_parameters</tt> with explicitly symbolized keys.
@@ -40,7 +42,7 @@ def symbolized_path_parameters
       #
       # See <tt>symbolized_path_parameters</tt> for symbolized keys.
       def path_parameters
-        @env[Routing::RouteSet::PARAMETERS_KEY] ||= {}
+        @env[PARAMETERS_KEY] ||= {}
       end
 
     private

actionpack/lib/action_dispatch/routing/route_set.rb

@@ -19,8 +19,6 @@ class RouteSet #:nodoc:
       # alias inspect to to_s.
       alias inspect to_s
 
-      PARAMETERS_KEY = 'action_dispatch.request.path_parameters'
-
       class Dispatcher < Routing::Endpoint #:nodoc:
         def initialize(defaults)
           @defaults = defaults

actionpack/test/controller/routing_test.rb

@@ -87,7 +87,7 @@ def setup
   def test_symbols_with_dashes
     rs.draw do
       get '/:artist/:song-omg', :to => lambda { |env|
-        resp = ActiveSupport::JSON.encode env[ActionDispatch::Routing::RouteSet::PARAMETERS_KEY]
+        resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
@@ -99,7 +99,7 @@ def test_symbols_with_dashes
   def test_id_with_dash
     rs.draw do
       get '/journey/:id', :to => lambda { |env|
-        resp = ActiveSupport::JSON.encode env[ActionDispatch::Routing::RouteSet::PARAMETERS_KEY]
+        resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
@@ -111,7 +111,7 @@ def test_id_with_dash
   def test_dash_with_custom_regexp
     rs.draw do
       get '/:artist/:song-omg', :constraints => { :song => /\d+/ }, :to => lambda { |env|
-        resp = ActiveSupport::JSON.encode env[ActionDispatch::Routing::RouteSet::PARAMETERS_KEY]
+        resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
@@ -124,7 +124,7 @@ def test_dash_with_custom_regexp
   def test_pre_dash
     rs.draw do
       get '/:artist/omg-:song', :to => lambda { |env|
-        resp = ActiveSupport::JSON.encode env[ActionDispatch::Routing::RouteSet::PARAMETERS_KEY]
+        resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end
@@ -136,7 +136,7 @@ def test_pre_dash
   def test_pre_dash_with_custom_regexp
     rs.draw do
       get '/:artist/omg-:song', :constraints => { :song => /\d+/ }, :to => lambda { |env|
-        resp = ActiveSupport::JSON.encode env[ActionDispatch::Routing::RouteSet::PARAMETERS_KEY]
+        resp = ActiveSupport::JSON.encode ActionDispatch::Request.new(env).path_parameters
         [200, {}, [resp]]
       }
     end