diff --git a/actionpack/lib/action_controller/testing/integration.rb b/actionpack/lib/action_controller/testing/integration.rb
index 8bba6dfd59..15d0603ac1 100644
--- a/actionpack/lib/action_controller/testing/integration.rb
+++ b/actionpack/lib/action_controller/testing/integration.rb
@@ -278,9 +278,7 @@ module ActionController
             "HTTP_ACCEPT"    => accept,
             "HTTP_COOKIE"    => cookies.inject("") { |string, (name, value)|
               string << "#{name}=#{value}; "
-            },
-
-            "rack.test"      => true
+            }
           }
           env = ActionDispatch::Test::MockRequest.env_for(@path, opts)
 
diff --git a/actionpack/lib/action_dispatch/http/request.rb b/actionpack/lib/action_dispatch/http/request.rb
index 523ab32b35..b8c547b696 100755
--- a/actionpack/lib/action_dispatch/http/request.rb
+++ b/actionpack/lib/action_dispatch/http/request.rb
@@ -397,7 +397,7 @@ EOM
     alias_method :params, :parameters
 
     def path_parameters=(parameters) #:nodoc:
-      @env["rack.routing_args"] = parameters
+      @env["action_dispatch.request.path_parameters"] = parameters
       @symbolized_path_parameters = @parameters = nil
     end
 
@@ -413,7 +413,7 @@ EOM
     #
     # See <tt>symbolized_path_parameters</tt> for symbolized keys.
     def path_parameters
-      @env["rack.routing_args"] ||= {}
+      @env["action_dispatch.request.path_parameters"] ||= {}
     end
 
     # The request body is an IO input stream. If the RAW_POST_DATA environment
diff --git a/actionpack/lib/action_dispatch/middleware/failsafe.rb b/actionpack/lib/action_dispatch/middleware/failsafe.rb
index 7379a696aa..b5a3abcc92 100644
--- a/actionpack/lib/action_dispatch/middleware/failsafe.rb
+++ b/actionpack/lib/action_dispatch/middleware/failsafe.rb
@@ -11,7 +11,7 @@ module ActionDispatch
       @app.call(env)
     rescue Exception => exception
       # Reraise exception in test environment
-      if env["rack.test"]
+      if defined?(Rails) && Rails.test?
         raise exception
       else
         failsafe_response(exception)