Remove Rescue middleware that was never used by Rails.

actionpack/lib/action_dispatch.rb

@@ -60,7 +60,6 @@ module ActionDispatch
     autoload :PublicExceptions
     autoload :Reloader
     autoload :RemoteIp
-    autoload :Rescue
     autoload :ShowExceptions
     autoload :Static
   end

actionpack/lib/action_dispatch/middleware/rescue.rb

-module ActionDispatch
-  class Rescue
-    def initialize(app, rescuers = {}, &block)
-      @app, @rescuers = app, {}
-      rescuers.each { |exception, rescuer| rescue_from(exception, rescuer) }
-      instance_eval(&block) if block_given?
-    end
-
-    def call(env)
-      @app.call(env)
-    rescue Exception => exception
-      if rescuer = @rescuers[exception.class.name]
-        env['action_dispatch.rescue.exception'] = exception
-        rescuer.call(env)
-      else
-        raise exception
-      end
-    end
-
-    protected
-      def rescue_from(exception, rescuer)
-        exception = exception.class.name if exception.is_a?(Exception)
-        @rescuers[exception.to_s] = rescuer
-      end
-  end
-end

actionpack/test/controller/rescue_test.rb

@@ -338,23 +338,8 @@ def show_errors(exception)
     end
   end
 
-  test 'rescue routing exceptions' do
-    raiser = proc { |env| raise ActionController::RoutingError, "Did not handle the request" }
-    @app = ActionDispatch::Rescue.new(raiser) do
-      rescue_from ActionController::RoutingError, lambda { |env| [200, {"Content-Type" => "text/html"}, ["Gotcha!"]] }
-    end
-
-    get '/b00m'
-    assert_equal "Gotcha!", response.body
-  end
-
-  test 'unrescued exception' do
-    raiser = proc { |env| raise ActionController::RoutingError, "Did not handle the request" }
-    @app = ActionDispatch::Rescue.new(raiser)
-    assert_raise(ActionController::RoutingError) { get '/b00m' }
-  end
-
   private
+
     def with_test_routing
       with_routing do |set|
         set.draw do