From 1494262977737a19c9840f5c501aaa62bc24161d Mon Sep 17 00:00:00 2001
From: Anil Wadghule <anildigital@gmail.com>
Date: Sun, 16 May 2010 21:23:37 +0530
Subject: [PATCH] Backport middleware stack from Rails 3 to Rails 2-3 [#4367 state:resolved]

---
 .../lib/action_controller/middleware_stack.rb      |   45 +++++++++++++-------
 1 files changed, 29 insertions(+), 16 deletions(-)

diff --git a/actionpack/lib/action_controller/middleware_stack.rb b/actionpack/lib/action_controller/middleware_stack.rb
index b739a6d..e24c431 100644
--- a/actionpack/lib/action_controller/middleware_stack.rb
+++ b/actionpack/lib/action_controller/middleware_stack.rb
@@ -27,15 +27,13 @@ module ActionController
       end
 
       def klass
-        if @klass.respond_to?(:call)
-          @klass.call
-        elsif @klass.is_a?(Class)
+        if @klass.respond_to?(:new)
           @klass
+        elsif @klass.respond_to?(:call)
+          @klass.call
         else
-          @klass.to_s.constantize
+          ActiveSupport::Inflector.constantize(@klass.to_s)
         end
-      rescue NameError
-        @klass
       end
 
       def active?
@@ -55,14 +53,16 @@ module ActionController
         when Class
           klass == middleware
         else
-          klass == middleware.to_s.constantize
+          if lazy_compare?(@klass) && lazy_compare?(middleware)
+            normalize(@klass) == normalize(middleware)
+          else
+            klass.name == middleware.to_s
+          end
         end
       end
 
       def inspect
-        str = klass.to_s
-        args.each { |arg| str += ", #{arg.inspect}" }
-        str
+        klass.to_s
       end
 
       def build(app)
@@ -75,9 +75,17 @@ module ActionController
 
       private
 
-        def build_args
-          Array(args).map { |arg| arg.respond_to?(:call) ? arg.call : arg }
-        end
+      def lazy_compare?(object)
+        object.is_a?(String) || object.is_a?(Symbol)
+      end
+
+      def normalize(object)
+        object.to_s.strip.sub(/^::/, '')
+      end
+
+      def build_args
+        Array(args).map { |arg| arg.respond_to?(:call) ? arg.call : arg }
+      end
     end
 
     def initialize(*args, &block)
@@ -94,8 +102,9 @@ module ActionController
     alias_method :insert_before, :insert
 
     def insert_after(index, *args, &block)
-      index = self.index(index) unless index.is_a?(Integer)
-      insert(index + 1, *args, &block)
+      i = index.is_a?(Integer) ? index : self.index(index)
+      raise "No such middleware to insert after: #{index.inspect}" unless i
+      insert(i + 1, *args, &block)
     end
 
     def swap(target, *args, &block)
@@ -112,7 +121,11 @@ module ActionController
       find_all { |middleware| middleware.active? }
     end
 
-    def build(app)
+    def build(app = nil, &blk)
+      app ||= blk
+
+      raise "MiddlewareStack#build requires an app" unless app
+
       active.reverse.inject(app) { |a, e| e.build(a) }
     end
   end
-- 
1.7.0.4