Merge branch 'master' of https://github.com/rails/rails into performance_test

Conflicts:
	activesupport/lib/active_support/testing/performance.rb

34 files changed, 860 insertions, 867 deletions

diff --git a/actionpack/lib/action_view/base.rb b/actionpack/lib/action_view/base.rb
index 9e8a3c51a3..c98110353f 100644
--- a/actionpack/lib/action_view/base.rb
+++ b/actionpack/lib/action_view/base.rb
@@ -131,12 +131,17 @@ module ActionView #:nodoc:
   #
   # More builder documentation can be found at http://builder.rubyforge.org.
   class Base
-    include Helpers, Rendering, Partials, ::ERB::Util, Context
+    include Helpers, ::ERB::Util, Context
 
     # Specify the proc used to decorate input tags that refer to attributes with errors.
     cattr_accessor :field_error_proc
     @@field_error_proc = Proc.new{ |html_tag, instance| "<div class=\"field_with_errors\">#{html_tag}</div>".html_safe }
 
+    # How to complete the streaming when an exception occurs.
+    # This is our best guess: first try to close the attribute, then the tag.
+    cattr_accessor :streaming_completion_on_exception
+    @@streaming_completion_on_exception = %("><script type="text/javascript">window.location = "/500.html"</script></html>)
+
     class_attribute :helpers
     class_attribute :_routes
 
@@ -151,56 +156,61 @@ module ActionView #:nodoc:
       def cache_template_loading=(value)
         ActionView::Resolver.caching = value
       end
-    end
-
-    attr_accessor :_template, :_view_flow
-    attr_internal :request, :controller, :config, :assigns, :lookup_context
-
-    delegate :formats, :formats=, :locale, :locale=, :view_paths, :view_paths=, :to => :lookup_context
 
-    delegate :request_forgery_protection_token, :params, :session, :cookies, :response, :headers,
-             :flash, :action_name, :controller_name, :to => :controller
+      def process_view_paths(value)
+        value.is_a?(PathSet) ?
+          value.dup : ActionView::PathSet.new(Array.wrap(value))
+      end
 
-    delegate :logger, :to => :controller, :allow_nil => true
+      def xss_safe? #:nodoc:
+        true
+      end
 
-    def self.xss_safe? #:nodoc:
-      true
+      # This method receives routes and helpers from the controller
+      # and return a subclass ready to be used as view context.
+      def prepare(routes, helpers) #:nodoc:
+        Class.new(self) do
+          if routes
+            include routes.url_helpers
+            include routes.mounted_helpers
+          end
+
+          if helpers
+            include helpers
+            self.helpers = helpers
+          end
+        end
+      end
     end
 
-    def self.process_view_paths(value)
-      value.is_a?(PathSet) ?
-        value.dup : ActionView::PathSet.new(Array.wrap(value))
-    end
+    attr_accessor :view_renderer
+    attr_internal :config, :assigns
+
+    delegate :lookup_context, :to => :view_renderer
+    delegate :formats, :formats=, :locale, :locale=, :view_paths, :view_paths=, :to => :lookup_context
 
     def assign(new_assigns) # :nodoc:
       @_assigns = new_assigns.each { |key, value| instance_variable_set("@#{key}", value) }
     end
 
-    def initialize(lookup_context = nil, assigns_for_first_render = {}, controller = nil, formats = nil) #:nodoc:
-      assign(assigns_for_first_render)
-      self.helpers = Module.new unless self.class.helpers
-
+    def initialize(context = nil, assigns = {}, controller = nil, formats = nil) #:nodoc:
       @_config = {}
-      @_virtual_path = nil
-      @_view_flow = OutputFlow.new
-      @output_buffer = nil
 
-      if @_controller = controller
-        @_request = controller.request if controller.respond_to?(:request)
-        @_config  = controller.config.inheritable_copy if controller.respond_to?(:config)
+      # Handle all these for backwards compatibility.
+      # TODO Provide a new API for AV::Base and deprecate this one.
+      if context.is_a?(ActionView::Renderer)
+        @view_renderer = context
+      elsif
+        lookup_context = context.is_a?(ActionView::LookupContext) ?
+          context : ActionView::LookupContext.new(context)
+        lookup_context.formats  = formats if formats
+        lookup_context.prefixes = controller._prefixes if controller
+        @view_renderer = ActionView::Renderer.new(lookup_context)
       end
 
-      @_lookup_context = lookup_context.is_a?(ActionView::LookupContext) ?
-        lookup_context : ActionView::LookupContext.new(lookup_context)
-      @_lookup_context.formats = formats if formats
-    end
-
-    def controller_path
-      @controller_path ||= controller && controller.controller_path
-    end
-
-    def controller_prefixes
-      @controller_prefixes ||= controller && controller._prefixes
+      assign(assigns)
+      assign_controller(controller)
+      _prepare_context
     end
 
     ActiveSupport.run_load_hooks(:action_view, self)
diff --git a/actionpack/lib/action_view/context.rb b/actionpack/lib/action_view/context.rb
index 39d88333e8..083856b2ca 100644
--- a/actionpack/lib/action_view/context.rb
+++ b/actionpack/lib/action_view/context.rb
@@ -2,38 +2,35 @@ module ActionView
   module CompiledTemplates #:nodoc:
     # holds compiled template code
   end
+
   # = Action View Context
   #
   # Action View contexts are supplied to Action Controller to render template.
   # The default Action View context is ActionView::Base.
   #
-  # In order to work with ActionController, a Context must implement:
-  #
-  # Context#render_partial[options]
-  #   - responsible for setting options[:_template]
-  #   - Returns String with the rendered partial
-  #   options<Hash>:: see _render_partial in ActionView::Base
-  # Context#render_template[template, layout, options, partial]
-  #   - Returns String with the rendered template
-  #   template<ActionView::Template>:: The template to render
-  #   layout<ActionView::Template>:: The layout to render around the template
-  #   options<Hash>:: See _render_template_with_layout in ActionView::Base
-  #   partial<Boolean>:: Whether or not the template to render is a partial
-  #
-  # An Action View context can also mix in Action View's helpers. In order to
-  # mix in helpers, a context must implement:
-  #
-  # Context#controller
-  # - Returns an instance of AbstractController
-  #
-  # In any case, a context must mix in ActionView::Context, which stores compiled
-  # template and provides the output buffer.
+  # In order to work with ActionController, a Context must just include this module.
+  # The initialization of the variables used by the context (@output_buffer, @view_flow,
+  # and @virtual_path) is responsibility of the object that includes this module
+  # (although you can call _prepare_context defined below).
   module Context
     include CompiledTemplates
-    attr_accessor :output_buffer
+    attr_accessor :output_buffer, :view_flow
+
+    # Prepares the context by setting the appropriate instance variables.
+    # :api: plugin
+    def _prepare_context
+      @view_flow     = OutputFlow.new
+      @output_buffer = nil
+      @virtual_path  = nil
+    end
 
-    def convert_to_model(object)
-      object.respond_to?(:to_model) ? object.to_model : object
+    # Encapsulates the interaction with the view flow so it
+    # returns the correct buffer on yield. This is usually
+    # overwriten by helpers to add more behavior.
+    # :api: plugin
+    def _layout_for(name=nil)
+      name ||= :layout
+      view_flow.get(name).html_safe
     end
   end
 end
\ No newline at end of file
diff --git a/actionpack/lib/action_view/flows.rb b/actionpack/lib/action_view/flows.rb
index 386a06511f..a8f740713f 100644
--- a/actionpack/lib/action_view/flows.rb
+++ b/actionpack/lib/action_view/flows.rb
@@ -34,7 +34,7 @@ module ActionView
       @view    = view
       @parent  = nil
       @child   = view.output_buffer
-      @content = view._view_flow.content
+      @content = view.view_flow.content
       @fiber   = fiber
       @root    = Fiber.current.object_id
     end
diff --git a/actionpack/lib/action_view/helpers.rb b/actionpack/lib/action_view/helpers.rb
index 205116f610..78a68db282 100644
--- a/actionpack/lib/action_view/helpers.rb
+++ b/actionpack/lib/action_view/helpers.rb
@@ -9,6 +9,7 @@ module ActionView #:nodoc:
     autoload :AtomFeedHelper
     autoload :CacheHelper
     autoload :CaptureHelper
+    autoload :ControllerHelper
     autoload :CsrfHelper
     autoload :DateHelper
     autoload :DebugHelper
@@ -19,6 +20,7 @@ module ActionView #:nodoc:
     autoload :NumberHelper
     autoload :OutputSafetyHelper
     autoload :RecordTagHelper
+    autoload :RenderingHelper
     autoload :SanitizeHelper
     autoload :SprocketsHelper
     autoload :TagHelper
@@ -38,6 +40,7 @@ module ActionView #:nodoc:
     include AtomFeedHelper
     include CacheHelper
     include CaptureHelper
+    include ControllerHelper
     include CsrfHelper
     include DateHelper
     include DebugHelper
@@ -48,6 +51,7 @@ module ActionView #:nodoc:
     include NumberHelper
     include OutputSafetyHelper
     include RecordTagHelper
+    include RenderingHelper
     include SanitizeHelper
     include SprocketsHelper
     include TagHelper
diff --git a/actionpack/lib/action_view/helpers/asset_paths.rb b/actionpack/lib/action_view/helpers/asset_paths.rb
new file mode 100644
index 0000000000..958f0e0a10
--- /dev/null
+++ b/actionpack/lib/action_view/helpers/asset_paths.rb
@@ -0,0 +1,79 @@
+require 'active_support/core_ext/file'
+require 'action_view/helpers/asset_paths'
+
+module ActionView
+  module Helpers
+
+    class AssetPaths #:nodoc:
+      attr_reader :config, :controller
+
+      def initialize(config, controller)
+        @config = config
+        @controller = controller
+      end
+
+      # Add the extension +ext+ if not present. Return full or scheme-relative URLs otherwise untouched.
+      # Prefix with <tt>/dir/</tt> if lacking a leading +/+. Account for relative URL
+      # roots. Rewrite the asset path for cache-busting asset ids. Include
+      # asset host, if configured, with the correct request protocol.
+      def compute_public_path(source, dir, ext = nil, include_host = true)
+        source = source.to_s
+        return source if is_uri?(source)
+
+        source = rewrite_extension(source, dir, ext) if ext
+        source = rewrite_asset_path(source, dir)
+
+        if controller && include_host
+          has_request = controller.respond_to?(:request)
+          source = rewrite_host_and_protocol(source, has_request)
+        end
+
+        source
+      end
+
+      def is_uri?(path)
+        path =~ %r{^[-a-z]+://|^cid:|^//}
+      end
+
+    private
+
+      def rewrite_extension(source, dir, ext)
+        raise NotImplementedError
+      end
+
+      def rewrite_asset_path(source, path = nil)
+        raise NotImplementedError
+      end
+
+      def rewrite_host_and_protocol(source, has_request)
+        host = compute_asset_host(source)
+        if has_request && host && !is_uri?(host)
+          host = "#{controller.request.protocol}#{host}"
+        end
+        "#{host}#{source}"
+      end
+
+      # Pick an asset host for this source. Returns +nil+ if no host is set,
+      # the host if no wildcard is set, the host interpolated with the
+      # numbers 0-3 if it contains <tt>%d</tt> (the number is the source hash mod 4),
+      # or the value returned from invoking the proc if it's a proc or the value from
+      # invoking call if it's an object responding to call.
+      def compute_asset_host(source)
+        if host = config.asset_host
+          if host.is_a?(Proc) || host.respond_to?(:call)
+            case host.is_a?(Proc) ? host.arity : host.method(:call).arity
+            when 2
+              request = controller.respond_to?(:request) && controller.request
+              host.call(source, request)
+            else
+              host.call(source)
+            end
+          else
+            (host =~ /%d/) ? host % (source.hash % 4) : host
+          end
+        end
+      end
+    end
+
+  end
+end
\ No newline at end of file
diff --git a/actionpack/lib/action_view/helpers/asset_tag_helper.rb b/actionpack/lib/action_view/helpers/asset_tag_helper.rb
index f6b2d4f3f4..9bc847a1ab 100644
--- a/actionpack/lib/action_view/helpers/asset_tag_helper.rb
+++ b/actionpack/lib/action_view/helpers/asset_tag_helper.rb
@@ -57,7 +57,7 @@ module ActionView
     # +asset_host+ to a proc like this:
     #
     #   ActionController::Base.asset_host = Proc.new { |source|
-    #     "http://assets#{source.hash % 2 + 1}.example.com"
+    #     "http://assets#{Digest::MD5.hexdigest(source).to_i(16) % 2 + 1}.example.com"
     #   }
     #   image_tag("rails.png")
     #   # => <img alt="Rails" src="http://assets1.example.com/images/rails.png?1230601161" />
@@ -268,13 +268,17 @@ module ActionView
       #   image_path("edit.png")                                     # => "/images/edit.png"
       #   image_path("icons/edit.png")                               # => "/images/icons/edit.png"
       #   image_path("/icons/edit.png")                              # => "/icons/edit.png"
-      #   image_path("http://www.railsapplication.com/img/edit.png") # => "http://www.railsapplication.com/img/edit.png"
+      #   image_path("http://www.example.com/img/edit.png")          # => "http://www.example.com/img/edit.png"
       #
       # If you have images as application resources this method may conflict with their named routes.
       # The alias +path_to_image+ is provided to avoid that. Rails uses the alias internally, and
       # plugin authors are encouraged to do so.
       def image_path(source)
-        asset_paths.compute_public_path(source, 'images')
+        if config.use_sprockets
+          asset_path(source)
+        else
+          asset_paths.compute_public_path(source, 'images')
+        end
       end
       alias_method :path_to_image, :image_path # aliased to avoid conflicts with an image_path named route
 
@@ -287,9 +291,13 @@ module ActionView
       #   video_path("hd.avi")                                        # => /videos/hd.avi
       #   video_path("trailers/hd.avi")                               # => /videos/trailers/hd.avi
       #   video_path("/trailers/hd.avi")                              # => /trailers/hd.avi
-      #   video_path("http://www.railsapplication.com/vid/hd.avi") # => http://www.railsapplication.com/vid/hd.avi
+      #   video_path("http://www.example.com/vid/hd.avi")             # => http://www.example.com/vid/hd.avi
       def video_path(source)
-        asset_paths.compute_public_path(source, 'videos')
+        if config.use_sprockets
+          asset_path(source)
+        else
+          asset_paths.compute_public_path(source, 'videos')
+        end
       end
       alias_method :path_to_video, :video_path # aliased to avoid conflicts with a video_path named route
 
@@ -302,9 +310,13 @@ module ActionView
       #   audio_path("horse.wav")                                        # => /audios/horse.wav
       #   audio_path("sounds/horse.wav")                                 # => /audios/sounds/horse.wav
       #   audio_path("/sounds/horse.wav")                                # => /sounds/horse.wav
-      #   audio_path("http://www.railsapplication.com/sounds/horse.wav") # => http://www.railsapplication.com/sounds/horse.wav
+      #   audio_path("http://www.example.com/sounds/horse.wav")          # => http://www.example.com/sounds/horse.wav
       def audio_path(source)
-        asset_paths.compute_public_path(source, 'audios')
+        if config.use_sprockets
+          asset_path(source)
+        else
+          asset_paths.compute_public_path(source, 'audios')
+        end
       end
       alias_method :path_to_audio, :audio_path # aliased to avoid conflicts with an audio_path named route
 
@@ -434,7 +446,7 @@ module ActionView
       private
 
         def asset_paths
-          @asset_paths ||= AssetPaths.new(config, controller)
+          @asset_paths ||= AssetTagHelper::AssetPaths.new(config, controller)
         end
     end
   end
diff --git a/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_include_tag.rb b/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_include_tag.rb
index 52eb43a1cd..e4662a2919 100644
--- a/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_include_tag.rb
+++ b/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_include_tag.rb
@@ -8,9 +8,11 @@ module ActionView
     module AssetTagHelper
 
       class AssetIncludeTag
-        attr_reader :config, :asset_paths
+        include TagHelper
 
+        attr_reader :config, :asset_paths
         class_attribute :expansions
+
         def self.inherited(base)
           base.expansions = { }
         end
@@ -56,7 +58,6 @@ module ActionView
           end
         end
 
-
         private
 
           def path_to_asset(source, include_host = true)
diff --git a/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_paths.rb b/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_paths.rb
index 1e00fd996b..cd0f8c8878 100644
--- a/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_paths.rb
+++ b/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_paths.rb
@@ -1,10 +1,11 @@
 require 'active_support/core_ext/file'
+require 'action_view/helpers/asset_paths'
 
 module ActionView
   module Helpers
     module AssetTagHelper
 
-      class AssetPaths
+      class AssetPaths < ActionView::Helpers::AssetPaths #:nodoc:
         # You can enable or disable the asset tag ids cache.
         # With the cache enabled, the asset tag helper methods will make fewer
         # expensive file system calls (the default implementation checks the file
@@ -14,31 +15,6 @@ module ActionView
         #   ActionView::Helpers::AssetTagHelper::AssetPaths.cache_asset_ids = false
         mattr_accessor :cache_asset_ids
 
-        attr_reader :config, :controller
-
-        def initialize(config, controller)
-          @config = config
-          @controller = controller
-        end
-
-        # Add the extension +ext+ if not present. Return full URLs otherwise untouched.
-        # Prefix with <tt>/dir/</tt> if lacking a leading +/+. Account for relative URL
-        # roots. Rewrite the asset path for cache-busting asset ids. Include
-        # asset host, if configured, with the correct request protocol.
-        def compute_public_path(source, dir, ext = nil, include_host = true)
-          return source if is_uri?(source)
-
-          source = rewrite_extension(source, dir, ext) if ext
-          source = "/#{dir}/#{source}" unless source[0] == ?/
-          source = rewrite_asset_path(source, config.asset_path)
-
-          has_request = controller.respond_to?(:request)
-          source = rewrite_relative_url_root(source, controller.config.relative_url_root) if has_request && include_host
-          source = rewrite_host_and_protocol(source, has_request) if include_host
-
-          source
-        end
-
         # Add or change an asset id in the asset id cache. This can be used
         # for SASS on Heroku.
         # :api: public
@@ -48,101 +24,76 @@ module ActionView
           end
         end
 
-        def is_uri?(path)
-          path =~ %r{^[-a-z]+://|^cid:}
-        end
+      private
 
-        private
+        def rewrite_extension(source, dir, ext)
+          source_ext = File.extname(source)
 
-          def rewrite_extension(source, dir, ext)
-            source_ext = File.extname(source)
+          source_with_ext = if source_ext.empty?
+            "#{source}.#{ext}"
+          elsif ext != source_ext[1..-1]
+            with_ext = "#{source}.#{ext}"
+            with_ext if File.exist?(File.join(config.assets_dir, dir, with_ext))
+          end
 
-            source_with_ext = if source_ext.empty?
-              "#{source}.#{ext}"
-            elsif ext != source_ext[1..-1]
-              with_ext = "#{source}.#{ext}"
-              with_ext if File.exist?(File.join(config.assets_dir, dir, with_ext))
-            end
+          source_with_ext || source
+        end
 
-            source_with_ext || source
-          end
+        # Break out the asset path rewrite in case plugins wish to put the asset id
+        # someplace other than the query string.
+        def rewrite_asset_path(source, dir)
+          source = "/#{dir}/#{source}" unless source[0] == ?/
+          path = config.asset_path
 
-          # Break out the asset path rewrite in case plugins wish to put the asset id
-          # someplace other than the query string.
-          def rewrite_asset_path(source, path = nil)
-            if path && path.respond_to?(:call)
-              return path.call(source)
-            elsif path && path.is_a?(String)
-              return path % [source]
-            end
+          if path && path.respond_to?(:call)
+            return path.call(source)
+          elsif path && path.is_a?(String)
+            return path % [source]
+          end
 
-            asset_id = rails_asset_id(source)
-            if asset_id.empty?
-              source
-            else
-              "#{source}?#{asset_id}"
-            end
+          asset_id = rails_asset_id(source)
+          if asset_id.empty?
+            source
+          else
+            "#{source}?#{asset_id}"
           end
+        end
 
-          mattr_accessor :asset_ids_cache
-          self.asset_ids_cache = {}
+        mattr_accessor :asset_ids_cache
+        self.asset_ids_cache = {}
 
-          mattr_accessor :asset_ids_cache_guard
-          self.asset_ids_cache_guard = Mutex.new
+        mattr_accessor :asset_ids_cache_guard
+        self.asset_ids_cache_guard = Mutex.new
 
-          # Use the RAILS_ASSET_ID environment variable or the source's
-          # modification time as its cache-busting asset id.
-          def rails_asset_id(source)
-            if asset_id = ENV["RAILS_ASSET_ID"]
+        # Use the RAILS_ASSET_ID environment variable or the source's
+        # modification time as its cache-busting asset id.
+        def rails_asset_id(source)
+          if asset_id = ENV["RAILS_ASSET_ID"]
+            asset_id
+          else
+            if self.cache_asset_ids && (asset_id = self.asset_ids_cache[source])
               asset_id
             else
-              if self.cache_asset_ids && (asset_id = self.asset_ids_cache[source])
-                asset_id
-              else
-                path = File.join(config.assets_dir, source)
-                asset_id = File.exist?(path) ? File.mtime(path).to_i.to_s : ''
-
-                if self.cache_asset_ids
-                  add_to_asset_ids_cache(source, asset_id)
-                end
+              path = File.join(config.assets_dir, source)
+              asset_id = File.exist?(path) ? File.mtime(path).to_i.to_s : ''
 
-                asset_id
+              if self.cache_asset_ids
+                add_to_asset_ids_cache(source, asset_id)
               end
-            end
-          end
-
-          def rewrite_relative_url_root(source, relative_url_root)
-            relative_url_root && !source.starts_with?("#{relative_url_root}/") ? "#{relative_url_root}#{source}" : source
-          end
 
-          def rewrite_host_and_protocol(source, has_request)
-            host = compute_asset_host(source)
-            if has_request && host && !is_uri?(host)
-              host = "#{controller.request.protocol}#{host}"
+              asset_id
             end
-            "#{host}#{source}"
           end
+        end
 
-          # Pick an asset host for this source. Returns +nil+ if no host is set,
-          # the host if no wildcard is set, the host interpolated with the
-          # numbers 0-3 if it contains <tt>%d</tt> (the number is the source hash mod 4),
-          # or the value returned from invoking the proc if it's a proc or the value from
-          # invoking call if it's an object responding to call.
-          def compute_asset_host(source)
-            if host = config.asset_host
-              if host.is_a?(Proc) || host.respond_to?(:call)
-                case host.is_a?(Proc) ? host.arity : host.method(:call).arity
-                when 2
-                  request = controller.respond_to?(:request) && controller.request
-                  host.call(source, request)
-                else
-                  host.call(source)
-                end
-              else
-                (host =~ /%d/) ? host % (source.hash % 4) : host
-              end
-            end
-          end
+        def rewrite_relative_url_root(source, relative_url_root)
+          relative_url_root && !source.starts_with?("#{relative_url_root}/") ? "#{relative_url_root}#{source}" : source
+        end
+
+        def rewrite_host_and_protocol(source, has_request)
+          source = rewrite_relative_url_root(source, controller.config.relative_url_root) if has_request
+          super(source, has_request)
+        end
       end
 
     end
diff --git a/actionpack/lib/action_view/helpers/asset_tag_helpers/javascript_tag_helpers.rb b/actionpack/lib/action_view/helpers/asset_tag_helpers/javascript_tag_helpers.rb
index ce5a7dc2e5..e1ee0d0e1a 100644
--- a/actionpack/lib/action_view/helpers/asset_tag_helpers/javascript_tag_helpers.rb
+++ b/actionpack/lib/action_view/helpers/asset_tag_helpers/javascript_tag_helpers.rb
@@ -1,6 +1,5 @@
 require 'active_support/concern'
 require 'active_support/core_ext/file'
-require 'action_view/helpers/tag_helper'
 require 'action_view/helpers/asset_tag_helpers/asset_include_tag'
 
 module ActionView
@@ -8,8 +7,6 @@ module ActionView
     module AssetTagHelper
 
       class JavascriptIncludeTag < AssetIncludeTag
-        include TagHelper
-
         def asset_name
           'javascript'
         end
@@ -80,14 +77,14 @@ module ActionView
         # Used internally by javascript_include_tag to build the script path.
         #
         # ==== Examples
-        #   javascript_path "xmlhr" # => /javascripts/xmlhr.js
-        #   javascript_path "dir/xmlhr.js" # => /javascripts/dir/xmlhr.js
-        #   javascript_path "/dir/xmlhr" # => /dir/xmlhr.js
-        #   javascript_path "http://www.railsapplication.com/js/xmlhr" # => http://www.railsapplication.com/js/xmlhr
-        #   javascript_path "http://www.railsapplication.com/js/xmlhr.js" # => http://www.railsapplication.com/js/xmlhr.js
+        #   javascript_path "xmlhr"                              # => /javascripts/xmlhr.js
+        #   javascript_path "dir/xmlhr.js"                       # => /javascripts/dir/xmlhr.js
+        #   javascript_path "/dir/xmlhr"                         # => /dir/xmlhr.js
+        #   javascript_path "http://www.example.com/js/xmlhr"    # => http://www.example.com/js/xmlhr
+        #   javascript_path "http://www.example.com/js/xmlhr.js" # => http://www.example.com/js/xmlhr.js
         def javascript_path(source)
           if config.use_sprockets
-            sprockets_javascript_path(source)
+            asset_path(source, 'js')
           else
             asset_paths.compute_public_path(source, 'javascripts', 'js')
           end
@@ -102,10 +99,9 @@ module ActionView
         #
         # When passing paths, the ".js" extension is optional.
         #
-        # To include the default JavaScript expansion pass <tt>:defaults</tt> as source.
-        # By default, <tt>:defaults</tt> loads jQuery. If the application was generated
-        # with "-j prototype" the libraries Prototype and Scriptaculous are loaded instead.
-        # In any case, the defaults can be overridden in <tt>config/application.rb</tt>:
+        # If the application is not using the asset pipeline, to include the default JavaScript
+        # expansion pass <tt>:defaults</tt> as source. By default, <tt>:defaults</tt> loads jQuery,
+        # and that can be overridden in <tt>config/application.rb</tt>:
         #
         #   config.action_view.javascript_expansions[:defaults] = %w(foo.js bar.js)
         #
@@ -126,11 +122,11 @@ module ActionView
         #   # => <script type="text/javascript" src="/javascripts/common.javascript?1284139606"></script>
         #   #    <script type="text/javascript" src="/elsewhere/cools.js?1423139606"></script>
         #
-        #   javascript_include_tag "http://www.railsapplication.com/xmlhr"
-        #   # => <script type="text/javascript" src="http://www.railsapplication.com/xmlhr.js?1284139606"></script>
+        #   javascript_include_tag "http://www.example.com/xmlhr"
+        #   # => <script type="text/javascript" src="http://www.example.com/xmlhr.js?1284139606"></script>
         #
-        #   javascript_include_tag "http://www.railsapplication.com/xmlhr.js"
-        #   # => <script type="text/javascript" src="http://www.railsapplication.com/xmlhr.js?1284139606"></script>
+        #   javascript_include_tag "http://www.example.com/xmlhr.js"
+        #   # => <script type="text/javascript" src="http://www.example.com/xmlhr.js?1284139606"></script>
         #
         #   javascript_include_tag :defaults
         #   # => <script type="text/javascript" src="/javascripts/jquery.js?1284139606"></script>
diff --git a/actionpack/lib/action_view/helpers/asset_tag_helpers/stylesheet_tag_helpers.rb b/actionpack/lib/action_view/helpers/asset_tag_helpers/stylesheet_tag_helpers.rb
index a994afb65e..a95eb221be 100644
--- a/actionpack/lib/action_view/helpers/asset_tag_helpers/stylesheet_tag_helpers.rb
+++ b/actionpack/lib/action_view/helpers/asset_tag_helpers/stylesheet_tag_helpers.rb
@@ -1,6 +1,5 @@
 require 'active_support/concern'
 require 'active_support/core_ext/file'
-require 'action_view/helpers/tag_helper'
 require 'action_view/helpers/asset_tag_helpers/asset_include_tag'
 
 module ActionView
@@ -8,8 +7,6 @@ module ActionView
     module AssetTagHelper
 
       class StylesheetIncludeTag < AssetIncludeTag
-        include TagHelper
-
         def asset_name
           'stylesheet'
         end
@@ -57,14 +54,14 @@ module ActionView
         # Used internally by +stylesheet_link_tag+ to build the stylesheet path.
         #
         # ==== Examples
-        #   stylesheet_path "style" # => /stylesheets/style.css
-        #   stylesheet_path "dir/style.css" # => /stylesheets/dir/style.css
-        #   stylesheet_path "/dir/style.css" # => /dir/style.css
-        #   stylesheet_path "http://www.railsapplication.com/css/style" # => http://www.railsapplication.com/css/style
-        #   stylesheet_path "http://www.railsapplication.com/css/style.css" # => http://www.railsapplication.com/css/style.css
+        #   stylesheet_path "style"                                  # => /stylesheets/style.css
+        #   stylesheet_path "dir/style.css"                          # => /stylesheets/dir/style.css
+        #   stylesheet_path "/dir/style.css"                         # => /dir/style.css
+        #   stylesheet_path "http://www.example.com/css/style"       # => http://www.example.com/css/style
+        #   stylesheet_path "http://www.example.com/css/style.css"   # => http://www.example.com/css/style.css
         def stylesheet_path(source)
           if config.use_sprockets
-            sprockets_stylesheet_path(source)
+            asset_path(source, 'css')
           else
             asset_paths.compute_public_path(source, 'stylesheets', 'css')
           end
@@ -82,8 +79,8 @@ module ActionView
         #   stylesheet_link_tag "style.css" # =>
         #     <link href="/stylesheets/style.css" media="screen" rel="stylesheet" type="text/css" />
         #
-        #   stylesheet_link_tag "http://www.railsapplication.com/style.css" # =>
-        #     <link href="http://www.railsapplication.com/style.css" media="screen" rel="stylesheet" type="text/css" />
+        #   stylesheet_link_tag "http://www.example.com/style.css" # =>
+        #     <link href="http://www.example.com/style.css" media="screen" rel="stylesheet" type="text/css" />
         #
         #   stylesheet_link_tag "style", :media => "all" # =>
         #     <link href="/stylesheets/style.css" media="all" rel="stylesheet" type="text/css" />
diff --git a/actionpack/lib/action_view/helpers/capture_helper.rb b/actionpack/lib/action_view/helpers/capture_helper.rb
index 0139714240..ead7feb091 100644
--- a/actionpack/lib/action_view/helpers/capture_helper.rb
+++ b/actionpack/lib/action_view/helpers/capture_helper.rb
@@ -135,7 +135,7 @@ module ActionView
       # for elements that will be fragment cached.
       def content_for(name, content = nil, &block)
         content = capture(&block) if block_given?
-        result = @_view_flow.append(name, content) if content
+        result = @view_flow.append(name, content) if content
         result unless content
       end
 
@@ -146,7 +146,7 @@ module ActionView
       # the layout to stop looking for more contents.
       def provide(name, content = nil, &block)
         content = capture(&block) if block_given?
-        result = @_view_flow.append!(name, content) if content
+        result = @view_flow.append!(name, content) if content
         result unless content
       end
 
@@ -169,7 +169,7 @@ module ActionView
       #   </body>
       #   </html>
       def content_for?(name)
-        @_view_flow.get(name).present?
+        @view_flow.get(name).present?
       end
 
       # Use an alternate output buffer for the duration of the block.
diff --git a/actionpack/lib/action_view/helpers/controller_helper.rb b/actionpack/lib/action_view/helpers/controller_helper.rb
new file mode 100644
index 0000000000..e22331cb3c
--- /dev/null
+++ b/actionpack/lib/action_view/helpers/controller_helper.rb
@@ -0,0 +1,21 @@
+module ActionView
+  module Helpers
+    # This module keeps all methods and behavior in ActionView
+    # that simply delegates to the controller.
+    module ControllerHelper #:nodoc:
+      attr_internal :controller, :request
+
+      delegate :request_forgery_protection_token, :params, :session, :cookies, :response, :headers,
+               :flash, :action_name, :controller_name, :controller_path, :to => :controller
+
+      delegate :logger, :to => :controller, :allow_nil => true
+
+      def assign_controller(controller)
+        if @_controller = controller
+          @_request = controller.request if controller.respond_to?(:request)
+          @_config  = controller.config.inheritable_copy if controller.respond_to?(:config)
+        end
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/actionpack/lib/action_view/helpers/date_helper.rb b/actionpack/lib/action_view/helpers/date_helper.rb
index 313a2591bf..d2ddaafcb3 100644
--- a/actionpack/lib/action_view/helpers/date_helper.rb
+++ b/actionpack/lib/action_view/helpers/date_helper.rb
@@ -51,7 +51,7 @@ module ActionView
       #   distance_of_time_in_words(from_time, from_time + 15.seconds)        # => less than a minute
       #   distance_of_time_in_words(from_time, from_time + 15.seconds, true)  # => less than 20 seconds
       #   distance_of_time_in_words(from_time, 3.years.from_now)              # => about 3 years
-      #   distance_of_time_in_words(from_time, from_time + 60.hours)          # => about 3 days
+      #   distance_of_time_in_words(from_time, from_time + 60.hours)          # => 3 days
       #   distance_of_time_in_words(from_time, from_time + 45.seconds, true)  # => less than a minute
       #   distance_of_time_in_words(from_time, from_time - 45.seconds, true)  # => less than a minute
       #   distance_of_time_in_words(from_time, 76.seconds.from_now)           # => 1 minute
@@ -94,9 +94,20 @@ module ActionView
             when 43200..86399    then locale.t :about_x_months, :count => 1
             when 86400..525599   then locale.t :x_months,       :count => (distance_in_minutes.to_f / 43200.0).round
             else
-              distance_in_years           = distance_in_minutes / 525600
-              minute_offset_for_leap_year = (distance_in_years / 4) * 1440
-              remainder                   = ((distance_in_minutes - minute_offset_for_leap_year) % 525600)
+              fyear = from_time.year
+              fyear += 1 if from_time.month >= 3
+              tyear = to_time.year
+              tyear -= 1 if to_time.month < 3
+              leap_years = (fyear > tyear) ? 0 : (fyear..tyear).count{|x| Date.leap?(x)}
+              minute_offset_for_leap_year = leap_years * 1440
+              # Discount the leap year days when calculating year distance.
+              # e.g. if there are 20 leap year days between 2 dates having the same day
+              # and month then the based on 365 days calculation
+              # the distance in years will come out to over 80 years when in written
+              # english it would read better as about 80 years.
+              minutes_with_offset         = distance_in_minutes - minute_offset_for_leap_year
+              remainder                   = (minutes_with_offset % 525600)
+              distance_in_years           = (minutes_with_offset / 525600)
               if remainder < 131400
                 locale.t(:about_x_years,  :count => distance_in_years)
               elsif remainder < 394200
@@ -112,10 +123,12 @@ module ActionView
       #
       # ==== Examples
       #   time_ago_in_words(3.minutes.from_now)       # => 3 minutes
-      #   time_ago_in_words(Time.now - 15.hours)      # => 15 hours
+      #   time_ago_in_words(Time.now - 15.hours)      # => about 15 hours
       #   time_ago_in_words(Time.now)                 # => less than a minute
       #
-      #   from_time = Time.now - 3.days - 14.minutes - 25.seconds     # => 3 days
+      #   from_time = Time.now - 3.days - 14.minutes - 25.seconds
+      #   time_ago_in_words(from_time)      # => 3 days
+      #
       def time_ago_in_words(from_time, include_seconds = false)
         distance_of_time_in_words(from_time, Time.now, include_seconds)
       end
@@ -205,7 +218,8 @@ module ActionView
 
       # Returns a set of select tags (one for hour, minute and optionally second) pre-selected for accessing a
       # specified time-based attribute (identified by +method+) on an object assigned to the template (identified by
-      # +object+). You can include the seconds with <tt>:include_seconds</tt>.
+      # +object+). You can include the seconds with <tt>:include_seconds</tt>. You can get hours in the AM/PM format
+      # with <tt>:ampm</tt> option.
       #
       # This method will also generate 3 input hidden tags, for the actual year, month and day unless the option
       # <tt>:ignore_date</tt> is set to +true+.
@@ -228,6 +242,9 @@ module ActionView
       #   time_select("post", "written_on", :prompt => {:hour => true}) # generic prompt for hours
       #   time_select("post", "written_on", :prompt => true) # generic prompts for all
       #
+      #   # You can set :ampm option to true which will show the hours as: 12 PM, 01 AM .. 11 PM.
+      #   time_select 'game', 'game_time', {:ampm => true}
+      #
       # The selects are prepared for multi-parameter assignment to an Active Record object.
       #
       # Note: If the day is not included as an option but the month is, the day will be set to the 1st to ensure that
@@ -255,6 +272,9 @@ module ActionView
       #   # be stored in the trip variable in the departing attribute.
       #   datetime_select("trip", "departing", :default => 3.days.from_now)
       #
+      #   # Generate a datetime select with hours in the AM/PM format
+      #   datetime_select("post", "written_on", :ampm => true)
+      #
       #   # Generates a datetime select that discards the type that, when POSTed, will be stored in the post variable
       #   # as the written_on attribute.
       #   datetime_select("post", "written_on", :discard_type => true)
@@ -304,6 +324,9 @@ module ActionView
       #   # my_date_time (four days after today)
       #   select_datetime(my_date_time, :discard_type => true)
       #
+      #   # Generate a datetime field with hours in the AM/PM format
+      #   select_datetime(my_date_time, :ampm => true)
+      #
       #   # Generates a datetime select that defaults to the datetime in my_date_time (four days after today)
       #   # prefixed with 'payday' rather than 'date'
       #   select_datetime(my_date_time, :prefix => 'payday')
@@ -385,6 +408,9 @@ module ActionView
       #   # separated by ':' and includes an input for seconds
       #   select_time(my_time, :time_separator => ':', :include_seconds => true)
       #
+      #   # Generate a time select field with hours in the AM/PM format
+      #   select_time(my_time, :ampm => true)
+      #
       #   # Generates a time select with a custom prompt. Use :prompt=>true for generic prompts.
       #   select_time(my_time, :prompt => {:day => 'Choose day', :month => 'Choose month', :year => 'Choose year'})
       #   select_time(my_time, :prompt => {:hour => true}) # generic prompt for hours
@@ -464,7 +490,10 @@ module ActionView
       #
       #   # Generates a select field for hours with a custom prompt.  Use :prompt => true for a
       #   # generic prompt.
-      #   select_hour(13, :prompt =>'Choose hour')
+      #   select_hour(13, :prompt => 'Choose hour')
+      #
+      #   # Generate a select field for hours in the AM/PM format
+      #   select_hour(my_time, :ampm => true)
       #
       def select_hour(datetime, options = {}, html_options = {})
         DateTimeSelector.new(datetime, options, html_options).select_hour
@@ -599,6 +628,15 @@ module ActionView
         :year => 1, :month => 2, :day => 3, :hour => 4, :minute => 5, :second => 6
       }.freeze
 
+      AMPM_TRANSLATION = Hash[
+        [[0, "12 AM"], [1, "01 AM"], [2, "02 AM"], [3, "03 AM"],
+         [4, "04 AM"], [5, "05 AM"], [6, "06 AM"], [7, "07 AM"],
+         [8, "08 AM"], [9, "09 AM"], [10, "10 AM"], [11, "11 AM"],
+         [12, "12 PM"], [13, "01 PM"], [14, "02 PM"], [15, "03 PM"],
+         [16, "04 PM"], [17, "05 PM"], [18, "06 PM"], [19, "07 PM"],
+         [20, "08 PM"], [21, "09 PM"], [22, "10 PM"], [23, "11 PM"]]
+      ].freeze
+
       def initialize(datetime, options = {}, html_options = {})
         @options      = options.dup
         @html_options = html_options.dup
@@ -690,7 +728,7 @@ module ActionView
         if @options[:use_hidden] || @options[:discard_hour]
           build_hidden(:hour, hour)
         else
-          build_options_and_select(:hour, hour, :end => 23)
+          build_options_and_select(:hour, hour, :end => 23, :ampm => @options[:ampm])
         end
       end
 
@@ -808,7 +846,7 @@ module ActionView
           start         = options.delete(:start) || 0
           stop          = options.delete(:end) || 59
           step          = options.delete(:step) || 1
-          options.reverse_merge!({:leading_zeros => true})
+          options.reverse_merge!({:leading_zeros => true, :ampm => false})
           leading_zeros = options.delete(:leading_zeros)
 
           select_options = []
@@ -816,7 +854,8 @@ module ActionView
             value = leading_zeros ? sprintf("%02d", i) : i
             tag_options = { :value => value }
             tag_options[:selected] = "selected" if selected == i
-            select_options << content_tag(:option, value, tag_options)
+            text = options[:ampm] ? AMPM_TRANSLATION[i] : value
+            select_options << content_tag(:option, text, tag_options)
           end
           (select_options.join("\n") + "\n").html_safe
         end
diff --git a/actionpack/lib/action_view/helpers/form_helper.rb b/actionpack/lib/action_view/helpers/form_helper.rb
index 440acafa88..b6bb90a3ce 100644
--- a/actionpack/lib/action_view/helpers/form_helper.rb
+++ b/actionpack/lib/action_view/helpers/form_helper.rb
@@ -102,6 +102,11 @@ module ActionView
       include FormTagHelper
       include UrlHelper
 
+      # Converts the given object to an ActiveModel compliant one.
+      def convert_to_model(object)
+        object.respond_to?(:to_model) ? object.to_model : object
+      end
+
       # Creates a form and a scope around a specific model object that is used
       # as a base for questioning about values for the fields.
       #
@@ -947,7 +952,8 @@ module ActionView
           label_tag(name_and_id["id"], options, &block)
         else
           content = if text.blank?
-            I18n.t("helpers.label.#{object_name}.#{method_name}", :default => "").presence
+            method_and_value = tag_value.present? ? "#{method_name}.#{tag_value}" : method_name
+            I18n.t("helpers.label.#{object_name}.#{method_and_value}", :default => "").presence
           else
             text.to_s
           end
@@ -1166,7 +1172,7 @@ module ActionView
     class FormBuilder
       # The methods which wrap a form helper call.
       class_attribute :field_helpers
-      self.field_helpers = (FormHelper.instance_method_names - ['form_for'])
+      self.field_helpers = FormHelper.instance_method_names - %w(form_for convert_to_model)
 
       attr_accessor :object_name, :object, :options
 
diff --git a/actionpack/lib/action_view/helpers/form_tag_helper.rb b/actionpack/lib/action_view/helpers/form_tag_helper.rb
index 49aa434020..9e0f8f32b7 100644
--- a/actionpack/lib/action_view/helpers/form_tag_helper.rb
+++ b/actionpack/lib/action_view/helpers/form_tag_helper.rb
@@ -74,6 +74,8 @@ module ActionView
       # ==== Options
       # * <tt>:multiple</tt> - If set to true the selection will allow multiple choices.
       # * <tt>:disabled</tt> - If set to true, the user will not be able to use this input.
+      # * <tt>:include_blank</tt> - If set to true, an empty option will be create
+      # * <tt>:prompt</tt> - Create a prompt option with blank value and the text asking user to select something
       # * Any other key creates standard HTML attributes for the tag.
       #
       # ==== Examples
@@ -99,18 +101,26 @@ module ActionView
       #   # => <select class="form_input" id="access" multiple="multiple" name="access[]"><option>Read</option>
       #   #    <option>Write</option></select>
       #
+      #   select_tag "people", options_from_collection_for_select(@people, "id", "name"), :include_blank => true
+      #   # => <select id="people" name="people"><option value=""></option><option value="1">David</option></select>
+      #
+      #   select_tag "people", options_from_collection_for_select(@people, "id", "name"), :prompt => "Select something"
+      #   # => <select id="people" name="people"><option value="">Select something</option><option value="1">David</option></select>
+      #
       #   select_tag "destination", "<option>NYC</option><option>Paris</option><option>Rome</option>", :disabled => true
       #   # => <select disabled="disabled" id="destination" name="destination"><option>NYC</option>
       #   #    <option>Paris</option><option>Rome</option></select>
       def select_tag(name, option_tags = nil, options = {})
         html_name = (options[:multiple] == true && !name.to_s.ends_with?("[]")) ? "#{name}[]" : name
-        if blank = options.delete(:include_blank)
-          if blank.kind_of?(String)
-            option_tags = "<option value=\"\">#{blank}</option>".html_safe + option_tags
-          else
-            option_tags = "<option value=\"\"></option>".html_safe + option_tags
-          end
+
+        if options.delete(:include_blank)
+          option_tags = "<option value=\"\"></option>".html_safe + option_tags
+        end
+
+        if prompt = options.delete(:prompt)
+          option_tags = "<option value=\"\">#{prompt}</option>".html_safe + option_tags
         end
+
         content_tag :select, option_tags, { "name" => html_name, "id" => sanitize_to_id(name) }.update(options.stringify_keys)
       end
 
diff --git a/actionpack/lib/action_view/helpers/number_helper.rb b/actionpack/lib/action_view/helpers/number_helper.rb
index 05a9c5b4f1..63d13a0f0b 100644
--- a/actionpack/lib/action_view/helpers/number_helper.rb
+++ b/actionpack/lib/action_view/helpers/number_helper.rb
@@ -100,7 +100,7 @@ module ActionView
       #  number_to_currency(1234567890.506, :precision => 3)  # => $1,234,567,890.506
       #  number_to_currency(1234567890.506, :locale => :fr)   # => 1 234 567 890,506 €
       #
-      #  number_to_currency(1234567890.50, :negative_format => "(%u%n)")
+      #  number_to_currency(-1234567890.50, :negative_format => "(%u%n)")
       #  # => ($1,234,567,890.51)
       #  number_to_currency(1234567890.50, :unit => "&pound;", :separator => ",", :delimiter => "")
       #  # => &pound;1234567890,50
@@ -238,7 +238,7 @@ module ActionView
       #  number_with_precision(111.2345, :precision => 1, :significant => true)     # => 100
       #  number_with_precision(13, :precision => 5, :significant => true)           # => 13.000
       #  number_with_precision(111.234, :locale => :fr)                             # => 111,234
-      #  number_with_precision(13, :precision => 5, :significant => true, strip_insignificant_zeros => true)
+      #  number_with_precision(13, :precision => 5, :significant => true, :strip_insignificant_zeros => true)
       #  # => 13
       #  number_with_precision(389.32314, :precision => 4, :significant => true)    # => 389.3
       #  number_with_precision(1111.2345, :precision => 2, :separator => ',', :delimiter => '.')
@@ -304,6 +304,7 @@ module ActionView
       # * <tt>:separator</tt>  - Sets the separator between the fractional and integer digits (defaults to ".").
       # * <tt>:delimiter</tt>  - Sets the thousands delimiter (defaults to "").
       # * <tt>:strip_insignificant_zeros</tt>  - If +true+ removes insignificant zeros after the decimal separator (defaults to +true+)
+      # * <tt>:prefix</tt>  - If +:si+ formats the number using the SI prefix (defaults to :binary)
       # ==== Examples
       #  number_to_human_size(123)                                          # => 123 Bytes
       #  number_to_human_size(1234)                                         # => 1.21 KB
@@ -318,7 +319,7 @@ module ActionView
       # Non-significant zeros after the fractional separator are stripped out by default (set
       # <tt>:strip_insignificant_zeros</tt> to +false+ to change that):
       #  number_to_human_size(1234567890123, :precision => 5)        # => "1.1229 TB"
-      #  number_to_human_size(524288000, :precision=>5)              # => "500 MB"
+      #  number_to_human_size(524288000, :precision => 5)            # => "500 MB"
       def number_to_human_size(number, options = {})
         options.symbolize_keys!
 
@@ -341,15 +342,17 @@ module ActionView
         options[:strip_insignificant_zeros] = true if not options.key?(:strip_insignificant_zeros)
 
         storage_units_format = I18n.translate(:'number.human.storage_units.format', :locale => options[:locale], :raise => true)
+        
+        base = options[:prefix] == :si ? 1000 : 1024
 
-        if number.to_i < 1024
+        if number.to_i < base
           unit = I18n.translate(:'number.human.storage_units.units.byte', :locale => options[:locale], :count => number.to_i, :raise => true)
           storage_units_format.gsub(/%n/, number.to_i.to_s).gsub(/%u/, unit).html_safe
         else
           max_exp  = STORAGE_UNITS.size - 1
-          exponent = (Math.log(number) / Math.log(1024)).to_i # Convert to base 1024
+          exponent = (Math.log(number) / Math.log(base)).to_i # Convert to base
           exponent = max_exp if exponent > max_exp # we need this to avoid overflow for the highest unit
-          number  /= 1024 ** exponent
+          number  /= base ** exponent
 
           unit_key = STORAGE_UNITS[exponent]
           unit = I18n.translate(:"number.human.storage_units.units.#{unit_key}", :locale => options[:locale], :count => number, :raise => true)
@@ -407,7 +410,7 @@ module ActionView
       # Unsignificant zeros after the decimal separator are stripped out by default (set
       # <tt>:strip_insignificant_zeros</tt> to +false+ to change that):
       #  number_to_human(12345012345, :significant_digits => 6)       # => "12.345 Billion"
-      #  number_to_human(500000000, :precision=>5)                    # => "500 Million"
+      #  number_to_human(500000000, :precision => 5)                  # => "500 Million"
       #
       # ==== Custom Unit Quantifiers
       #
diff --git a/actionpack/lib/action_view/helpers/record_tag_helper.rb b/actionpack/lib/action_view/helpers/record_tag_helper.rb
index 4d300a1469..142a25f118 100644
--- a/actionpack/lib/action_view/helpers/record_tag_helper.rb
+++ b/actionpack/lib/action_view/helpers/record_tag_helper.rb
@@ -10,7 +10,7 @@ module ActionView
       # relate to the specified Active Record object. Usage example:
       #
       #    <%= div_for(@person, :class => "foo") do %>
-      #       <%=h @person.name %>
+      #       <%= @person.name %>
       #    <% end %>
       #
       # produces:
@@ -25,8 +25,8 @@ module ActionView
       # that relate to the specified Active Record object. For example:
       #
       #    <%= content_tag_for(:tr, @person) do %>
-      #      <td><%=h @person.first_name %></td>
-      #      <td><%=h @person.last_name %></td>
+      #      <td><%= @person.first_name %></td>
+      #      <td><%= @person.last_name %></td>
       #    <% end %>
       #
       # would produce the following HTML (assuming @person is an instance of
diff --git a/actionpack/lib/action_view/helpers/rendering_helper.rb b/actionpack/lib/action_view/helpers/rendering_helper.rb
new file mode 100644
index 0000000000..47efdded42
--- /dev/null
+++ b/actionpack/lib/action_view/helpers/rendering_helper.rb
@@ -0,0 +1,90 @@
+module ActionView
+  module Helpers
+    # = Action View Rendering
+    #
+    # Implements methods that allow rendering from a view context.
+    # In order to use this module, all you need is to implement
+    # view_renderer that returns an ActionView::Renderer object.
+    module RenderingHelper
+      # Returns the result of a render that's dictated by the options hash. The primary options are:
+      #
+      # * <tt>:partial</tt> - See ActionView::Partials.
+      # * <tt>:file</tt> - Renders an explicit template file (this used to be the old default), add :locals to pass in those.
+      # * <tt>:inline</tt> - Renders an inline template similar to how it's done in the controller.
+      # * <tt>:text</tt> - Renders the text passed in out.
+      #
+      # If no options hash is passed or :update specified, the default is to render a partial and use the second parameter
+      # as the locals hash.
+      def render(options = {}, locals = {}, &block)
+        case options
+        when Hash
+          if block_given?
+            view_renderer.render_partial(self, options.merge(:partial => options[:layout]), &block)
+          else
+            view_renderer.render(self, options)
+          end
+        else
+          view_renderer.render_partial(self, :partial => options, :locals => locals)
+        end
+      end
+
+      # Overwrites _layout_for in the context object so it supports the case a block is
+      # passed to a partial. Returns the contents that are yielded to a layout, given a
+      # name or a block.
+      #
+      # You can think of a layout as a method that is called with a block. If the user calls
+      # <tt>yield :some_name</tt>, the block, by default, returns <tt>content_for(:some_name)</tt>.
+      # If the user calls simply +yield+, the default block returns <tt>content_for(:layout)</tt>.
+      #
+      # The user can override this default by passing a block to the layout:
+      #
+      #   # The template
+      #   <%= render :layout => "my_layout" do %>
+      #     Content
+      #   <% end %>
+      #
+      #   # The layout
+      #   <html>
+      #     <%= yield %>
+      #   </html>
+      #
+      # In this case, instead of the default block, which would return <tt>content_for(:layout)</tt>,
+      # this method returns the block that was passed in to <tt>render :layout</tt>, and the response
+      # would be
+      #
+      #   <html>
+      #     Content
+      #   </html>
+      #
+      # Finally, the block can take block arguments, which can be passed in by +yield+:
+      #
+      #   # The template
+      #   <%= render :layout => "my_layout" do |customer| %>
+      #     Hello <%= customer.name %>
+      #   <% end %>
+      #
+      #   # The layout
+      #   <html>
+      #     <%= yield Struct.new(:name).new("David") %>
+      #   </html>
+      #
+      # In this case, the layout would receive the block passed into <tt>render :layout</tt>,
+      # and the struct specified would be passed into the block as an argument. The result
+      # would be
+      #
+      #   <html>
+      #     Hello David
+      #   </html>
+      #
+      def _layout_for(*args, &block)
+        name = args.first
+
+        if block && !name.is_a?(Symbol)
+          capture(*args, &block)
+        else
+          super
+        end
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/actionpack/lib/action_view/helpers/sanitize_helper.rb b/actionpack/lib/action_view/helpers/sanitize_helper.rb
index 0fee34f8a4..841be0a567 100644
--- a/actionpack/lib/action_view/helpers/sanitize_helper.rb
+++ b/actionpack/lib/action_view/helpers/sanitize_helper.rb
@@ -94,7 +94,7 @@ module ActionView
       #   # => Please e-mail me at me@email.com.
       #
       #   strip_links('Blog: <a href="http://www.myblog.com/" class="nav" target=\"_blank\">Visit</a>.')
-      #   # => Blog: Visit
+      #   # => Blog: Visit.
       def strip_links(html)
         self.class.link_sanitizer.sanitize(html)
       end
diff --git a/actionpack/lib/action_view/helpers/sprockets_helper.rb b/actionpack/lib/action_view/helpers/sprockets_helper.rb
index 408a2030ab..ab98da9624 100644
--- a/actionpack/lib/action_view/helpers/sprockets_helper.rb
+++ b/actionpack/lib/action_view/helpers/sprockets_helper.rb
@@ -1,85 +1,69 @@
 require 'uri'
+require 'action_view/helpers/asset_paths'
 
 module ActionView
   module Helpers
     module SprocketsHelper
-      def sprockets_javascript_path(source)
-        compute_sprockets_path source, 'assets', 'js'
+      def asset_path(source, default_ext = nil)
+        sprockets_asset_paths.compute_public_path(source, 'assets', default_ext, true)
       end
 
       def sprockets_javascript_include_tag(source, options = {})
         options = {
           'type' => "text/javascript",
-          'src'  => sprockets_javascript_path(source)
+          'src'  => asset_path(source, 'js')
         }.merge(options.stringify_keys)
 
         content_tag 'script', "", options
       end
 
-      def sprockets_stylesheet_path(source)
-        compute_sprockets_path source, 'assets', 'css'
-      end
-
       def sprockets_stylesheet_link_tag(source, options = {})
         options = {
           'rel'   => "stylesheet",
           'type'  => "text/css",
           'media' => "screen",
-          'href'  => sprockets_stylesheet_path(source)
+          'href'  => asset_path(source, 'css')
         }.merge(options.stringify_keys)
 
         tag 'link', options
       end
 
       private
-        def compute_sprockets_path(source, dir, default_ext)
-          source = source.to_s
-
-          return source if URI.parse(source).host
-
-          # Add /javscripts to relative paths
-          if source[0] != ?/
-            source = "/#{dir}/#{source}"
-          end
-
-          # Add default extension if there isn't one
-          if default_ext && File.extname(source).empty?
-            source = "#{source}.#{default_ext}"
-          end
 
-          # Fingerprint url
-          if source =~ /^\/#{dir}\/(.+)/
-            source = assets.path($1, config.perform_caching, dir)
-          end
-
-          host = compute_asset_host(source)
+      def sprockets_asset_paths
+        @sprockets_asset_paths ||= begin
+          config     = self.config if respond_to?(:config)
+          controller = self.controller if respond_to?(:controller)
+          SprocketsHelper::AssetPaths.new(config, controller)
+        end
+      end
 
-          if controller.respond_to?(:request) && host && URI.parse(host).host
-            source = "#{controller.request.protocol}#{host}#{source}"
+      class AssetPaths < ActionView::Helpers::AssetPaths #:nodoc:
+        def rewrite_asset_path(source, dir)
+          if source[0] == ?/
+            source
+          else
+            assets.path(source, performing_caching?, dir)
           end
-
-          source
         end
 
-        def compute_asset_host(source)
-          if host = config.asset_host
-            if host.is_a?(Proc) || host.respond_to?(:call)
-              case host.is_a?(Proc) ? host.arity : host.method(:call).arity
-              when 2
-                request = controller.respond_to?(:request) && controller.request
-                host.call(source, request)
-              else
-                host.call(source)
-              end
-            else
-              (host =~ /%d/) ? host % (source.hash % 4) : host
-            end
+        def rewrite_extension(source, dir, ext)
+          if ext && File.extname(source).empty?
+            "#{source}.#{ext}"
+          else
+            source
           end
         end
 
         def assets
           Rails.application.assets
         end
+
+        # When included in Sprockets::Context, we need to ask the top-level config as the controller is not available
+        def performing_caching?
+          @config ?  @config.perform_caching : Rails.application.config.action_controller.perform_caching
+        end
+      end
     end
   end
-end
+end
\ No newline at end of file
diff --git a/actionpack/lib/action_view/helpers/text_helper.rb b/actionpack/lib/action_view/helpers/text_helper.rb
index bdda1df437..ca09c77b5c 100644
--- a/actionpack/lib/action_view/helpers/text_helper.rb
+++ b/actionpack/lib/action_view/helpers/text_helper.rb
@@ -19,7 +19,7 @@ module ActionView
     #   simple_format('<a href="http://example.com/">Example</a>')
     #   # => "<p><a href=\"http://example.com/\">Example</a></p>"
     #
-    #   simple_format('<a href="javascript:alert('no!')">Example</a>')
+    #   simple_format('<a href="javascript:alert(\'no!\')">Example</a>')
     #   # => "<p><a>Example</a></p>"
     #
     # If you want to escape all content, you should invoke the +h+ method before
@@ -265,60 +265,6 @@ module ActionView
         text.html_safe.safe_concat("</p>")
       end
 
-      # Turns all URLs and e-mail addresses into clickable links. The <tt>:link</tt> option
-      # will limit what should be linked. You can add HTML attributes to the links using
-      # <tt>:html</tt>. Possible values for <tt>:link</tt> are <tt>:all</tt> (default),
-      # <tt>:email_addresses</tt>, and <tt>:urls</tt>. If a block is given, each URL and
-      # e-mail address is yielded and the result is used as the link text.
-      #
-      # ==== Examples
-      #   auto_link("Go to http://www.rubyonrails.org and say hello to david@loudthinking.com")
-      #   # => "Go to <a href=\"http://www.rubyonrails.org\">http://www.rubyonrails.org</a> and
-      #   #     say hello to <a href=\"mailto:david@loudthinking.com\">david@loudthinking.com</a>"
-      #
-      #   auto_link("Visit http://www.loudthinking.com/ or e-mail david@loudthinking.com", :link => :urls)
-      #   # => "Visit <a href=\"http://www.loudthinking.com/\">http://www.loudthinking.com/</a>
-      #   #     or e-mail david@loudthinking.com"
-      #
-      #   auto_link("Visit http://www.loudthinking.com/ or e-mail david@loudthinking.com", :link => :email_addresses)
-      #   # => "Visit http://www.loudthinking.com/ or e-mail <a href=\"mailto:david@loudthinking.com\">david@loudthinking.com</a>"
-      #
-      #   post_body = "Welcome to my new blog at http://www.myblog.com/.  Please e-mail me at me@email.com."
-      #   auto_link(post_body, :html => { :target => '_blank' }) do |text|
-      #     truncate(text, :length => 15)
-      #   end
-      #   # => "Welcome to my new blog at <a href=\"http://www.myblog.com/\" target=\"_blank\">http://www.m...</a>.
-      #         Please e-mail me at <a href=\"mailto:me@email.com\">me@email.com</a>."
-      #
-      #
-      # You can still use <tt>auto_link</tt> with the old API that accepts the
-      # +link+ as its optional second parameter and the +html_options+ hash
-      # as its optional third parameter:
-      #   post_body = "Welcome to my new blog at http://www.myblog.com/. Please e-mail me at me@email.com."
-      #   auto_link(post_body, :urls)     # => Once upon\na time
-      #   # => "Welcome to my new blog at <a href=\"http://www.myblog.com/\">http://www.myblog.com</a>.
-      #         Please e-mail me at me@email.com."
-      #
-      #   auto_link(post_body, :all, :target => "_blank")     # => Once upon\na time
-      #   # => "Welcome to my new blog at <a href=\"http://www.myblog.com/\" target=\"_blank\">http://www.myblog.com</a>.
-      #         Please e-mail me at <a href=\"mailto:me@email.com\">me@email.com</a>."
-      def auto_link(text, *args, &block)#link = :all, html = {}, &block)
-        return '' if text.blank?
-
-        options = args.size == 2 ? {} : args.extract_options! # this is necessary because the old auto_link API has a Hash as its last parameter
-        unless args.empty?
-          options[:link] = args[0] || :all
-          options[:html] = args[1] || {}
-        end
-        options.reverse_merge!(:link => :all, :html => {})
-
-        case options[:link].to_sym
-          when :all                         then auto_link_email_addresses(auto_link_urls(text, options[:html], options, &block), options[:html], &block)
-          when :email_addresses             then auto_link_email_addresses(text, options[:html], &block)
-          when :urls                        then auto_link_urls(text, options[:html], options, &block)
-        end
-      end
-
       # Creates a Cycle object whose _to_s_ method cycles through elements of an
       # array every time it is called. This can be used for example, to alternate
       # classes for table rows.  You can use named cycles to allow nesting in loops.
@@ -464,77 +410,6 @@ module ActionView
           @_cycles = Hash.new unless defined?(@_cycles)
           @_cycles[name] = cycle_object
         end
-
-        AUTO_LINK_RE = %r{
-            (?: ([0-9A-Za-z+.:-]+:)// | www\. )
-            [^\s<]+
-          }x
-
-        # regexps for determining context, used high-volume
-        AUTO_LINK_CRE = [/<[^>]+$/, /^[^>]*>/, /<a\b.*?>/i, /<\/a>/i]
-
-        AUTO_EMAIL_RE = /[\w.!#\$%+-]+@[\w-]+(?:\.[\w-]+)+/
-
-        BRACKETS = { ']' => '[', ')' => '(', '}' => '{' }
-
-        # Turns all urls into clickable links.  If a block is given, each url
-        # is yielded and the result is used as the link text.
-        def auto_link_urls(text, html_options = {}, options = {})
-          link_attributes = html_options.stringify_keys
-          text.gsub(AUTO_LINK_RE) do
-            scheme, href = $1, $&
-            punctuation = []
-
-            if auto_linked?($`, $')
-              # do not change string; URL is already linked
-              href
-            else
-              # don't include trailing punctuation character as part of the URL
-              while href.sub!(/[^\w\/-]$/, '')
-                punctuation.push $&
-                if opening = BRACKETS[punctuation.last] and href.scan(opening).size > href.scan(punctuation.last).size
-                  href << punctuation.pop
-                  break
-                end
-              end
-
-              link_text = block_given?? yield(href) : href
-              href = 'http://' + href unless scheme
-
-              unless options[:sanitize] == false
-                link_text = sanitize(link_text)
-                href      = sanitize(href)
-              end
-              content_tag(:a, link_text, link_attributes.merge('href' => href), !!options[:sanitize]) + punctuation.reverse.join('')
-            end
-          end
-        end
-
-        # Turns all email addresses into clickable links.  If a block is given,
-        # each email is yielded and the result is used as the link text.
-        def auto_link_email_addresses(text, html_options = {}, options = {})
-          text.gsub(AUTO_EMAIL_RE) do
-            text = $&
-
-            if auto_linked?($`, $')
-              text.html_safe
-            else
-              display_text = (block_given?) ? yield(text) : text
-
-              unless options[:sanitize] == false
-                text         = sanitize(text)
-                display_text = sanitize(display_text) unless text == display_text
-              end
-              mail_to text, display_text, html_options
-            end
-          end
-        end
-
-        # Detects already linked context or position in the middle of a tag
-        def auto_linked?(left, right)
-          (left =~ AUTO_LINK_CRE[0] and right =~ AUTO_LINK_CRE[1]) or
-            (left.rindex(AUTO_LINK_CRE[2]) and $' !~ AUTO_LINK_CRE[3])
-        end
     end
   end
 end
diff --git a/actionpack/lib/action_view/helpers/translation_helper.rb b/actionpack/lib/action_view/helpers/translation_helper.rb
index 59e6ce878f..ec9bdd5320 100644
--- a/actionpack/lib/action_view/helpers/translation_helper.rb
+++ b/actionpack/lib/action_view/helpers/translation_helper.rb
@@ -5,7 +5,7 @@ module I18n
   class ExceptionHandler
     include Module.new {
       def call(exception, locale, key, options)
-        exception.is_a?(MissingTranslationData) ? super.html_safe : super
+        exception.is_a?(MissingTranslation) ? super.html_safe : super
       end
     }
   end
@@ -17,8 +17,8 @@ module ActionView
     module TranslationHelper
       # Delegates to I18n#translate but also performs three additional functions.
       #
-      # First, it'll pass the :rescue_format => :html option to I18n so that any caught
-      # MissingTranslationData exceptions will be turned into inline spans that
+      # First, it'll pass the :rescue_format => :html option to I18n so that any
+      # thrown MissingTranslation messages will be turned into inline spans that
       #
       #   * have a "translation-missing" class set,
       #   * contain the missing key as a title attribute and
@@ -63,8 +63,8 @@ module ActionView
       private
         def scope_key_by_partial(key)
           if key.to_s.first == "."
-            if (path = @_template && @_template.virtual_path)
-              path.gsub(%r{/_?}, ".") + key.to_s
+            if @virtual_path
+              @virtual_path.gsub(%r{/_?}, ".") + key.to_s
             else
               raise "Cannot use t(#{key.inspect}) shortcut because path is not available"
             end
diff --git a/actionpack/lib/action_view/helpers/url_helper.rb b/actionpack/lib/action_view/helpers/url_helper.rb
index de75488e72..ffa9a5bb0b 100644
--- a/actionpack/lib/action_view/helpers/url_helper.rb
+++ b/actionpack/lib/action_view/helpers/url_helper.rb
@@ -68,7 +68,7 @@ module ActionView
       #   # => /books/find
       #
       #   <%= url_for(:action => 'login', :controller => 'members', :only_path => false, :protocol => 'https') %>
-      #   # => https://www.railsapplication.com/members/login/
+      #   # => https://www.example.com/members/login/
       #
       #   <%= url_for(:action => 'play', :anchor => 'player') %>
       #   # => /messages/play/#player
@@ -555,10 +555,10 @@ module ActionView
       #   current_page?(:controller => 'shop', :action => 'checkout')
       #   # => true
       #
-      #   current_page?(:controller => 'shop', :action => 'checkout', :order => 'desc', :page=>'1')
+      #   current_page?(:controller => 'shop', :action => 'checkout', :order => 'desc', :page => '1')
       #   # => true
       #
-      #   current_page?(:controller => 'shop', :action => 'checkout', :order => 'desc', :page=>'2')
+      #   current_page?(:controller => 'shop', :action => 'checkout', :order => 'desc', :page => '2')
       #   # => false
       #
       #   current_page?(:controller => 'shop', :action => 'checkout', :order => 'desc')
diff --git a/actionpack/lib/action_view/lookup_context.rb b/actionpack/lib/action_view/lookup_context.rb
index 06c607931d..f0ed3425de 100644
--- a/actionpack/lib/action_view/lookup_context.rb
+++ b/actionpack/lib/action_view/lookup_context.rb
@@ -9,6 +9,8 @@ module ActionView
   # generate a key, given to view paths, used in the resolver cache lookup. Since
   # this key is generated just once during the request, it speeds up all cache accesses.
   class LookupContext #:nodoc:
+    attr_accessor :prefixes
+    
     mattr_accessor :fallbacks
     @@fallbacks = FallbackFileSystemResolver.instances
 
@@ -58,10 +60,11 @@ module ActionView
       end
     end
 
-    def initialize(view_paths, details = {})
+    def initialize(view_paths, details = {}, prefixes = [])
       @details, @details_key = { :handlers => default_handlers }, nil
       @frozen_formats, @skip_default_locale = false, false
       @cache = true
+      @prefixes = prefixes
 
       self.view_paths = view_paths
       self.registered_detail_setters.each do |key, setter|
@@ -164,12 +167,12 @@ module ActionView
         @frozen_formats = true
       end
 
-      # Overload formats= to reject ["*/*"] values.
+      # Overload formats= to expand ["*/*"] values and automatically
+      # add :html as fallback to :js.
       def formats=(values)
-        if values && values.size == 1
-          value = values.first
-          values = nil    if value == "*/*"
-          values << :html if value == :js
+        if values
+          values.concat(_formats_defaults) if values.delete "*/*"
+          values << :html if values == [:js]
         end
         super(values)
       end
diff --git a/actionpack/lib/action_view/partials.rb b/actionpack/lib/action_view/partials.rb
deleted file mode 100644
index c181689e62..0000000000
--- a/actionpack/lib/action_view/partials.rb
+++ /dev/null
@@ -1,226 +0,0 @@
-require 'active_support/core_ext/object/blank'
-
-module ActionView
-  # = Action View Partials
-  #
-  # There's also a convenience method for rendering sub templates within the current controller that depends on a
-  # single object (we call this kind of sub templates for partials). It relies on the fact that partials should
-  # follow the naming convention of being prefixed with an underscore -- as to separate them from regular
-  # templates that could be rendered on their own.
-  #
-  # In a template for Advertiser#account:
-  #
-  #  <%= render :partial => "account" %>
-  #
-  # This would render "advertiser/_account.html.erb" and pass the instance variable @account in as a local variable
-  # +account+ to the template for display.
-  #
-  # In another template for Advertiser#buy, we could have:
-  #
-  #   <%= render :partial => "account", :locals => { :account => @buyer } %>
-  #
-  #   <% @advertisements.each do |ad| %>
-  #     <%= render :partial => "ad", :locals => { :ad => ad } %>
-  #   <% end %>
-  #
-  # This would first render "advertiser/_account.html.erb" with @buyer passed in as the local variable +account+, then
-  # render "advertiser/_ad.html.erb" and pass the local variable +ad+ to the template for display.
-  #
-  # == The :as and :object options
-  #
-  # By default <tt>ActionView::Partials::PartialRenderer</tt> has its object in a local variable with the same
-  # name as the template. So, given
-  #
-  #   <%= render :partial => "contract" %>
-  #
-  # within contract we'll get <tt>@contract</tt> in the local variable +contract+, as if we had written
-  #
-  #   <%= render :partial => "contract", :locals => { :contract  => @contract } %>
-  #
-  # With the <tt>:as</tt> option we can specify a different name for said local variable. For example, if we
-  # wanted it to be +agreement+ instead of +contract+ we'd do:
-  #
-  #   <%= render :partial => "contract", :as => 'agreement' %>
-  #
-  # The <tt>:object</tt> option can be used to directly specify which object is rendered into the partial;
-  # useful when the template's object is elsewhere, in a different ivar or in a local variable for instance.
-  #
-  # Revisiting a previous example we could have written this code:
-  #
-  #   <%= render :partial => "account", :object => @buyer %>
-  #
-  #   <% @advertisements.each do |ad| %>
-  #     <%= render :partial => "ad", :object => ad %>
-  #   <% end %>
-  #
-  # The <tt>:object</tt> and <tt>:as</tt> options can be used together.
-  #
-  # == Rendering a collection of partials
-  #
-  # The example of partial use describes a familiar pattern where a template needs to iterate over an array and
-  # render a sub template for each of the elements. This pattern has been implemented as a single method that
-  # accepts an array and renders a partial by the same name as the elements contained within. So the three-lined
-  # example in "Using partials" can be rewritten with a single line:
-  #
-  #   <%= render :partial => "ad", :collection => @advertisements %>
-  #
-  # This will render "advertiser/_ad.html.erb" and pass the local variable +ad+ to the template for display. An
-  # iteration counter will automatically be made available to the template with a name of the form
-  # +partial_name_counter+. In the case of the example above, the template would be fed +ad_counter+.
-  #
-  # The <tt>:as</tt> option may be used when rendering partials.
-  #
-  # You can specify a partial to be rendered between elements via the <tt>:spacer_template</tt> option.
-  # The following example will render <tt>advertiser/_ad_divider.html.erb</tt> between each ad partial:
-  #
-  #   <%= render :partial => "ad", :collection => @advertisements, :spacer_template => "ad_divider" %>
-  #
-  # If the given <tt>:collection</tt> is nil or empty, <tt>render</tt> will return nil. This will allow you
-  # to specify a text which will displayed instead by using this form:
-  #
-  #   <%= render(:partial => "ad", :collection => @advertisements) || "There's no ad to be displayed" %>
-  #
-  # NOTE: Due to backwards compatibility concerns, the collection can't be one of hashes. Normally you'd also
-  # just keep domain objects, like Active Records, in there.
-  #
-  # == Rendering shared partials
-  #
-  # Two controllers can share a set of partials and render them like this:
-  #
-  #   <%= render :partial => "advertisement/ad", :locals => { :ad => @advertisement } %>
-  #
-  # This will render the partial "advertisement/_ad.html.erb" regardless of which controller this is being called from.
-  #
-  # == Rendering objects with the RecordIdentifier
-  #
-  # Instead of explicitly naming the location of a partial, you can also let the RecordIdentifier do the work if
-  # you're following its conventions for RecordIdentifier#partial_path. Examples:
-  #
-  #  # @account is an Account instance, so it uses the RecordIdentifier to replace
-  #  # <%= render :partial => "accounts/account", :locals => { :account => @account} %>
-  #  <%= render :partial => @account %>
-  #
-  #  # @posts is an array of Post instances, so it uses the RecordIdentifier to replace
-  #  # <%= render :partial => "posts/post", :collection => @posts %>
-  #  <%= render :partial => @posts %>
-  #
-  # == Rendering the default case
-  #
-  # If you're not going to be using any of the options like collections or layouts, you can also use the short-hand
-  # defaults of render to render partials. Examples:
-  #
-  #  # Instead of <%= render :partial => "account" %>
-  #  <%= render "account" %>
-  #
-  #  # Instead of <%= render :partial => "account", :locals => { :account => @buyer } %>
-  #  <%= render "account", :account => @buyer %>
-  #
-  #  # @account is an Account instance, so it uses the RecordIdentifier to replace
-  #  # <%= render :partial => "accounts/account", :locals => { :account => @account } %>
-  #  <%= render(@account) %>
-  #
-  #  # @posts is an array of Post instances, so it uses the RecordIdentifier to replace
-  #  # <%= render :partial => "posts/post", :collection => @posts %>
-  #  <%= render(@posts) %>
-  #
-  # == Rendering partials with layouts
-  #
-  # Partials can have their own layouts applied to them. These layouts are different than the ones that are
-  # specified globally for the entire action, but they work in a similar fashion. Imagine a list with two types
-  # of users:
-  #
-  #   <%# app/views/users/index.html.erb &>
-  #   Here's the administrator:
-  #   <%= render :partial => "user", :layout => "administrator", :locals => { :user => administrator } %>
-  #
-  #   Here's the editor:
-  #   <%= render :partial => "user", :layout => "editor", :locals => { :user => editor } %>
-  #
-  #   <%# app/views/users/_user.html.erb &>
-  #   Name: <%= user.name %>
-  #
-  #   <%# app/views/users/_administrator.html.erb &>
-  #   <div id="administrator">
-  #     Budget: $<%= user.budget %>
-  #     <%= yield %>
-  #   </div>
-  #
-  #   <%# app/views/users/_editor.html.erb &>
-  #   <div id="editor">
-  #     Deadline: <%= user.deadline %>
-  #     <%= yield %>
-  #   </div>
-  #
-  # ...this will return:
-  #
-  #   Here's the administrator:
-  #   <div id="administrator">
-  #     Budget: $<%= user.budget %>
-  #     Name: <%= user.name %>
-  #   </div>
-  #
-  #   Here's the editor:
-  #   <div id="editor">
-  #     Deadline: <%= user.deadline %>
-  #     Name: <%= user.name %>
-  #   </div>
-  #
-  # You can also apply a layout to a block within any template:
-  #
-  #   <%# app/views/users/_chief.html.erb &>
-  #   <%= render(:layout => "administrator", :locals => { :user => chief }) do %>
-  #     Title: <%= chief.title %>
-  #   <% end %>
-  #
-  # ...this will return:
-  #
-  #   <div id="administrator">
-  #     Budget: $<%= user.budget %>
-  #     Title: <%= chief.name %>
-  #   </div>
-  #
-  # As you can see, the <tt>:locals</tt> hash is shared between both the partial and its layout.
-  #
-  # If you pass arguments to "yield" then this will be passed to the block. One way to use this is to pass
-  # an array to layout and treat it as an enumerable.
-  #
-  #   <%# app/views/users/_user.html.erb &>
-  #   <div class="user">
-  #     Budget: $<%= user.budget %>
-  #     <%= yield user %>
-  #   </div>
-  #
-  #   <%# app/views/users/index.html.erb &>
-  #   <%= render :layout => @users do |user| %>
-  #     Title: <%= user.title %>
-  #   <% end %>
-  #
-  # This will render the layout for each user and yield to the block, passing the user, each time.
-  #
-  # You can also yield multiple times in one layout and use block arguments to differentiate the sections.
-  #
-  #   <%# app/views/users/_user.html.erb &>
-  #   <div class="user">
-  #     <%= yield user, :header %>
-  #     Budget: $<%= user.budget %>
-  #     <%= yield user, :footer %>
-  #   </div>
-  #
-  #   <%# app/views/users/index.html.erb &>
-  #   <%= render :layout => @users do |user, section| %>
-  #     <%- case section when :header -%>
-  #       Title: <%= user.title %>
-  #     <%- when :footer -%>
-  #       Deadline: <%= user.deadline %>
-  #     <%- end -%>
-  #   <% end %>
-  module Partials
-    def _render_partial(options, &block) #:nodoc:
-      _partial_renderer.setup(options, block).render
-    end
-
-    def _partial_renderer #:nodoc:
-      @_partial_renderer ||= PartialRenderer.new(self)
-    end
-  end
-end
diff --git a/actionpack/lib/action_view/railtie.rb b/actionpack/lib/action_view/railtie.rb
index f20ba7e6d3..80391d72cc 100644
--- a/actionpack/lib/action_view/railtie.rb
+++ b/actionpack/lib/action_view/railtie.rb
@@ -6,7 +6,7 @@ module ActionView
   class Railtie < Rails::Railtie
     config.action_view = ActiveSupport::OrderedOptions.new
     config.action_view.stylesheet_expansions = {}
-    config.action_view.javascript_expansions = { :defaults => %w(jquery rails) }
+    config.action_view.javascript_expansions = { :defaults => %w(jquery jquery_ujs) }
 
     initializer "action_view.cache_asset_ids" do |app|
       unless app.config.cache_classes
diff --git a/actionpack/lib/action_view/renderer/abstract_renderer.rb b/actionpack/lib/action_view/renderer/abstract_renderer.rb
index 4a52b3172e..60c527beeb 100644
--- a/actionpack/lib/action_view/renderer/abstract_renderer.rb
+++ b/actionpack/lib/action_view/renderer/abstract_renderer.rb
@@ -3,9 +3,8 @@ module ActionView
     delegate :find_template, :template_exists?, :with_fallbacks, :update_details,
       :with_layout_format, :formats, :freeze_formats, :to => :@lookup_context
 
-    def initialize(view)
-      @view = view
-      @lookup_context = view.lookup_context
+    def initialize(lookup_context)
+      @lookup_context = lookup_context
     end
 
     def render
diff --git a/actionpack/lib/action_view/renderer/partial_renderer.rb b/actionpack/lib/action_view/renderer/partial_renderer.rb
index 10cd37d56f..a351fbc04f 100644
--- a/actionpack/lib/action_view/renderer/partial_renderer.rb
+++ b/actionpack/lib/action_view/renderer/partial_renderer.rb
@@ -1,44 +1,230 @@
+require 'active_support/core_ext/object/blank'
+
 module ActionView
+  # = Action View Partials
+  #
+  # There's also a convenience method for rendering sub templates within the current controller that depends on a
+  # single object (we call this kind of sub templates for partials). It relies on the fact that partials should
+  # follow the naming convention of being prefixed with an underscore -- as to separate them from regular
+  # templates that could be rendered on their own.
+  #
+  # In a template for Advertiser#account:
+  #
+  #  <%= render :partial => "account" %>
+  #
+  # This would render "advertiser/_account.html.erb" and pass the instance variable @account in as a local variable
+  # +account+ to the template for display.
+  #
+  # In another template for Advertiser#buy, we could have:
+  #
+  #   <%= render :partial => "account", :locals => { :account => @buyer } %>
+  #
+  #   <% @advertisements.each do |ad| %>
+  #     <%= render :partial => "ad", :locals => { :ad => ad } %>
+  #   <% end %>
+  #
+  # This would first render "advertiser/_account.html.erb" with @buyer passed in as the local variable +account+, then
+  # render "advertiser/_ad.html.erb" and pass the local variable +ad+ to the template for display.
+  #
+  # == The :as and :object options
+  #
+  # By default <tt>ActionView::Partials::PartialRenderer</tt> has its object in a local variable with the same
+  # name as the template. So, given
+  #
+  #   <%= render :partial => "contract" %>
+  #
+  # within contract we'll get <tt>@contract</tt> in the local variable +contract+, as if we had written
+  #
+  #   <%= render :partial => "contract", :locals => { :contract  => @contract } %>
+  #
+  # With the <tt>:as</tt> option we can specify a different name for said local variable. For example, if we
+  # wanted it to be +agreement+ instead of +contract+ we'd do:
+  #
+  #   <%= render :partial => "contract", :as => 'agreement' %>
+  #
+  # The <tt>:object</tt> option can be used to directly specify which object is rendered into the partial;
+  # useful when the template's object is elsewhere, in a different ivar or in a local variable for instance.
+  #
+  # Revisiting a previous example we could have written this code:
+  #
+  #   <%= render :partial => "account", :object => @buyer %>
+  #
+  #   <% @advertisements.each do |ad| %>
+  #     <%= render :partial => "ad", :object => ad %>
+  #   <% end %>
+  #
+  # The <tt>:object</tt> and <tt>:as</tt> options can be used together.
+  #
+  # == Rendering a collection of partials
+  #
+  # The example of partial use describes a familiar pattern where a template needs to iterate over an array and
+  # render a sub template for each of the elements. This pattern has been implemented as a single method that
+  # accepts an array and renders a partial by the same name as the elements contained within. So the three-lined
+  # example in "Using partials" can be rewritten with a single line:
+  #
+  #   <%= render :partial => "ad", :collection => @advertisements %>
+  #
+  # This will render "advertiser/_ad.html.erb" and pass the local variable +ad+ to the template for display. An
+  # iteration counter will automatically be made available to the template with a name of the form
+  # +partial_name_counter+. In the case of the example above, the template would be fed +ad_counter+.
+  #
+  # The <tt>:as</tt> option may be used when rendering partials.
+  #
+  # You can specify a partial to be rendered between elements via the <tt>:spacer_template</tt> option.
+  # The following example will render <tt>advertiser/_ad_divider.html.erb</tt> between each ad partial:
+  #
+  #   <%= render :partial => "ad", :collection => @advertisements, :spacer_template => "ad_divider" %>
+  #
+  # If the given <tt>:collection</tt> is nil or empty, <tt>render</tt> will return nil. This will allow you
+  # to specify a text which will displayed instead by using this form:
+  #
+  #   <%= render(:partial => "ad", :collection => @advertisements) || "There's no ad to be displayed" %>
+  #
+  # NOTE: Due to backwards compatibility concerns, the collection can't be one of hashes. Normally you'd also
+  # just keep domain objects, like Active Records, in there.
+  #
+  # == Rendering shared partials
+  #
+  # Two controllers can share a set of partials and render them like this:
+  #
+  #   <%= render :partial => "advertisement/ad", :locals => { :ad => @advertisement } %>
+  #
+  # This will render the partial "advertisement/_ad.html.erb" regardless of which controller this is being called from.
+  #
+  # == Rendering objects with the RecordIdentifier
+  #
+  # Instead of explicitly naming the location of a partial, you can also let the RecordIdentifier do the work if
+  # you're following its conventions for RecordIdentifier#partial_path. Examples:
+  #
+  #  # @account is an Account instance, so it uses the RecordIdentifier to replace
+  #  # <%= render :partial => "accounts/account", :locals => { :account => @account} %>
+  #  <%= render :partial => @account %>
+  #
+  #  # @posts is an array of Post instances, so it uses the RecordIdentifier to replace
+  #  # <%= render :partial => "posts/post", :collection => @posts %>
+  #  <%= render :partial => @posts %>
+  #
+  # == Rendering the default case
+  #
+  # If you're not going to be using any of the options like collections or layouts, you can also use the short-hand
+  # defaults of render to render partials. Examples:
+  #
+  #  # Instead of <%= render :partial => "account" %>
+  #  <%= render "account" %>
+  #
+  #  # Instead of <%= render :partial => "account", :locals => { :account => @buyer } %>
+  #  <%= render "account", :account => @buyer %>
+  #
+  #  # @account is an Account instance, so it uses the RecordIdentifier to replace
+  #  # <%= render :partial => "accounts/account", :locals => { :account => @account } %>
+  #  <%= render(@account) %>
+  #
+  #  # @posts is an array of Post instances, so it uses the RecordIdentifier to replace
+  #  # <%= render :partial => "posts/post", :collection => @posts %>
+  #  <%= render(@posts) %>
+  #
+  # == Rendering partials with layouts
+  #
+  # Partials can have their own layouts applied to them. These layouts are different than the ones that are
+  # specified globally for the entire action, but they work in a similar fashion. Imagine a list with two types
+  # of users:
+  #
+  #   <%# app/views/users/index.html.erb &>
+  #   Here's the administrator:
+  #   <%= render :partial => "user", :layout => "administrator", :locals => { :user => administrator } %>
+  #
+  #   Here's the editor:
+  #   <%= render :partial => "user", :layout => "editor", :locals => { :user => editor } %>
+  #
+  #   <%# app/views/users/_user.html.erb &>
+  #   Name: <%= user.name %>
+  #
+  #   <%# app/views/users/_administrator.html.erb &>
+  #   <div id="administrator">
+  #     Budget: $<%= user.budget %>
+  #     <%= yield %>
+  #   </div>
+  #
+  #   <%# app/views/users/_editor.html.erb &>
+  #   <div id="editor">
+  #     Deadline: <%= user.deadline %>
+  #     <%= yield %>
+  #   </div>
+  #
+  # ...this will return:
+  #
+  #   Here's the administrator:
+  #   <div id="administrator">
+  #     Budget: $<%= user.budget %>
+  #     Name: <%= user.name %>
+  #   </div>
+  #
+  #   Here's the editor:
+  #   <div id="editor">
+  #     Deadline: <%= user.deadline %>
+  #     Name: <%= user.name %>
+  #   </div>
+  #
+  # You can also apply a layout to a block within any template:
+  #
+  #   <%# app/views/users/_chief.html.erb &>
+  #   <%= render(:layout => "administrator", :locals => { :user => chief }) do %>
+  #     Title: <%= chief.title %>
+  #   <% end %>
+  #
+  # ...this will return:
+  #
+  #   <div id="administrator">
+  #     Budget: $<%= user.budget %>
+  #     Title: <%= chief.name %>
+  #   </div>
+  #
+  # As you can see, the <tt>:locals</tt> hash is shared between both the partial and its layout.
+  #
+  # If you pass arguments to "yield" then this will be passed to the block. One way to use this is to pass
+  # an array to layout and treat it as an enumerable.
+  #
+  #   <%# app/views/users/_user.html.erb &>
+  #   <div class="user">
+  #     Budget: $<%= user.budget %>
+  #     <%= yield user %>
+  #   </div>
+  #
+  #   <%# app/views/users/index.html.erb &>
+  #   <%= render :layout => @users do |user| %>
+  #     Title: <%= user.title %>
+  #   <% end %>
+  #
+  # This will render the layout for each user and yield to the block, passing the user, each time.
+  #
+  # You can also yield multiple times in one layout and use block arguments to differentiate the sections.
+  #
+  #   <%# app/views/users/_user.html.erb &>
+  #   <div class="user">
+  #     <%= yield user, :header %>
+  #     Budget: $<%= user.budget %>
+  #     <%= yield user, :footer %>
+  #   </div>
+  #
+  #   <%# app/views/users/index.html.erb &>
+  #   <%= render :layout => @users do |user, section| %>
+  #     <%- case section when :header -%>
+  #       Title: <%= user.title %>
+  #     <%- when :footer -%>
+  #       Deadline: <%= user.deadline %>
+  #     <%- end -%>
+  #   <% end %>
   class PartialRenderer < AbstractRenderer #:nodoc:
     PARTIAL_NAMES = Hash.new {|h,k| h[k] = {} }
 
-    def initialize(view)
+    def initialize(*)
       super
-      @partial_names = PARTIAL_NAMES[@view.controller.class.name]
+      @partial_names = PARTIAL_NAMES[@lookup_context.prefixes.first]
     end
 
-    def setup(options, block)
-      partial = options[:partial]
-
-      @options = options
-      @locals  = options[:locals] || {}
-      @block   = block
-
-      if String === partial
-        @object     = options[:object]
-        @path       = partial
-        @collection = collection
-      else
-        @object = partial
-
-        if @collection = collection_from_object || collection
-          paths = @collection_data = @collection.map { |o| partial_path(o) }
-          @path = paths.uniq.size == 1 ? paths.first : nil
-        else
-          @path = partial_path
-        end
-      end
-
-      if @path
-        @variable, @variable_counter = retrieve_variable(@path)
-      else
-        paths.map! { |path| retrieve_variable(path).unshift(path) }
-      end
-
-      self
-    end
+    def render(context, options, block)
+      setup(context, options, block)
 
-    def render
       wrap_formats(@path) do
         identifier = ((@template = find_partial) ? @template.identifier : @path)
 
@@ -77,7 +263,7 @@ module ActionView
       locals[as] = object
 
       content = @template.render(view, locals) do |*name|
-        view._block_layout_for(*name, &block)
+        view._layout_for(*name, &block)
       end
 
       content = layout.render(view, locals){ content } if layout
@@ -86,6 +272,38 @@ module ActionView
 
     private
 
+    def setup(context, options, block)
+      @view   = context
+      partial = options[:partial]
+
+      @options = options
+      @locals  = options[:locals] || {}
+      @block   = block
+
+      if String === partial
+        @object     = options[:object]
+        @path       = partial
+        @collection = collection
+      else
+        @object = partial
+
+        if @collection = collection_from_object || collection
+          paths = @collection_data = @collection.map { |o| partial_path(o) }
+          @path = paths.uniq.size == 1 ? paths.first : nil
+        else
+          @path = partial_path
+        end
+      end
+
+      if @path
+        @variable, @variable_counter = retrieve_variable(@path)
+      else
+        paths.map! { |path| retrieve_variable(path).unshift(path) }
+      end
+
+      self
+    end
+
     def collection
       if @options.key?(:collection)
         collection = @options[:collection]
@@ -109,7 +327,7 @@ module ActionView
     end
 
     def find_template(path=@path, locals=@locals.keys)
-      prefixes = path.include?(?/) ? [] : @view.controller_prefixes
+      prefixes = path.include?(?/) ? [] : @lookup_context.prefixes
       @lookup_context.find_template(path, prefixes, true, locals)
     end
 
@@ -150,7 +368,7 @@ module ActionView
         object = object.to_model if object.respond_to?(:to_model)
 
         object.class.model_name.partial_path.dup.tap do |partial|
-          path = @view.controller_prefixes.first
+          path = @lookup_context.prefixes.first
           partial.insert(0, "#{File.dirname(path)}/") if partial.include?(?/) && path.include?(?/)
         end
       end
diff --git a/actionpack/lib/action_view/renderer/renderer.rb b/actionpack/lib/action_view/renderer/renderer.rb
new file mode 100644
index 0000000000..bf1b5a7d22
--- /dev/null
+++ b/actionpack/lib/action_view/renderer/renderer.rb
@@ -0,0 +1,54 @@
+module ActionView
+  # This is the main entry point for rendering. It basically delegates
+  # to other objects like TemplateRenderer and PartialRenderer which
+  # actually renders the template.
+  class Renderer
+    attr_accessor :lookup_context
+
+    def initialize(lookup_context)
+      @lookup_context = lookup_context
+    end
+
+    # Main render entry point shared by AV and AC.
+    def render(context, options)
+      if options.key?(:partial)
+        render_partial(context, options)
+      else
+        render_template(context, options)
+      end
+    end
+
+    # Render but returns a valid Rack body. If fibers are defined, we return
+    # a streaming body that renders the template piece by piece.
+    #
+    # Note that partials are not supported to be rendered with streaming,
+    # so in such cases, we just wrap them in an array.
+    def render_body(context, options)
+      if options.key?(:partial)
+        [render_partial(context, options)]
+      else
+        StreamingTemplateRenderer.new(@lookup_context).render(context, options)
+      end
+    end
+
+    # Direct accessor to template rendering.
+    def render_template(context, options) #:nodoc:
+      _template_renderer.render(context, options)
+    end
+
+    # Direct access to partial rendering.
+    def render_partial(context, options, &block) #:nodoc:
+      _partial_renderer.render(context, options, block)
+    end
+
+    private
+
+    def _template_renderer #:nodoc:
+      @_template_renderer ||= TemplateRenderer.new(@lookup_context)
+    end
+
+    def _partial_renderer #:nodoc:
+      @_partial_renderer ||= PartialRenderer.new(@lookup_context)
+    end
+  end
+end
diff --git a/actionpack/lib/action_view/renderer/streaming_template_renderer.rb b/actionpack/lib/action_view/renderer/streaming_template_renderer.rb
index 52f0e9f5bd..1ccf5a8ddb 100644
--- a/actionpack/lib/action_view/renderer/streaming_template_renderer.rb
+++ b/actionpack/lib/action_view/renderer/streaming_template_renderer.rb
@@ -4,53 +4,11 @@
 require 'fiber' if defined?(Fiber)
 
 module ActionView
-  # Consider the following layout:
-  # 
-  #   <%= yield :header %>
-  #   2
-  #   <%= yield %>
-  #   5
-  #   <%= yield :footer %>
-  #
-  # And template:
-  #
-  #     <%= provide :header, "1" %>
-  #     3
-  #     4
-  #     <%= provide :footer, "6" %>
-  # 
-  # It will stream:
-  # 
-  #     "1\n", "2\n", "3\n4\n", "5\n", "6\n"
-  #
-  # Notice that once you <%= yield %>, it will render the whole template
-  # before streaming again. In the future, we can also support streaming
-  # from the template and not only the layout.
-  #
-  # Also, notice we use +provide+ instead of +content_for+, as +provide+
-  # gives the control back to the layout as soon as it is called.
-  # With +content_for+, it would render all the template to find all
-  # +content_for+ calls. For instance, consider this layout:
-  #
-  #   <%= yield :header %>
-  #
-  # With this template:
-  #
-  #   <%= content_for :header, "1" %>
-  #   <%= provide :header, "2" %>
-  #   <%= provide :header, "3" %>
-  #
-  # It will return "12\n" because +content_for+ continues rendering the
-  # template but it is returns back to the layout as soon as it sees the
-  # first +provide+.
-  #
   # == TODO
   #
-  # * Add streaming support in the controllers with no-cache settings
-  # * What should happen when an error happens?
   # * Support streaming from child templates, partials and so on.
-  # * Support on sprockets async JS load?
-  #
+  # * Integrate exceptions with exceptron
+  # * Rack::Cache needs to support streaming bodies
   class StreamingTemplateRenderer < TemplateRenderer #:nodoc:
     # A valid Rack::Body (i.e. it responds to each).
     # It is initialized with a block that, when called, starts
@@ -61,9 +19,28 @@ module ActionView
       end
 
       def each(&block)
-        @start.call(block)
+        begin
+          @start.call(block)
+        rescue Exception => exception
+          log_error(exception)
+          block.call ActionView::Base.streaming_completion_on_exception
+        end
         self
       end
+
+      private
+
+      # This is the same logging logic as in ShowExceptions middleware.
+      # TODO Once "exceptron" is in, refactor this piece to simply re-use exceptron.
+      def log_error(exception) #:nodoc:
+        logger = ActionController::Base.logger
+        return unless logger
+
+        message = "\n#{exception.class} (#{exception.message}):\n"
+        message << exception.annoted_source_code.to_s if exception.respond_to?(:annoted_source_code)
+        message << "  " << exception.backtrace.join("\n  ")
+        logger.fatal("#{message}\n\n")
+      end
     end
 
     # For streaming, instead of rendering a given a template, we return a Body
@@ -105,7 +82,7 @@ module ActionView
         # Set the view flow to support streaming. It will be aware
         # when to stop rendering the layout because it needs to search
         # something in the template and vice-versa.
-        view._view_flow = StreamingFlow.new(view, fiber)
+        view.view_flow = StreamingFlow.new(view, fiber)
 
         # Yo! Start the fiber!
         fiber.resume
@@ -117,7 +94,7 @@ module ActionView
           content = template.render(view, locals, &yielder)
 
           # Once rendering the template is done, sets its content in the :layout key.
-          view._view_flow.set(:layout, content)
+          view.view_flow.set(:layout, content)
 
           # In case the layout continues yielding, we need to resume
           # the fiber until all yields are handled.
diff --git a/actionpack/lib/action_view/renderer/template_renderer.rb b/actionpack/lib/action_view/renderer/template_renderer.rb
index 6b5ead463f..a09cef8fef 100644
--- a/actionpack/lib/action_view/renderer/template_renderer.rb
+++ b/actionpack/lib/action_view/renderer/template_renderer.rb
@@ -3,7 +3,9 @@ require 'active_support/core_ext/array/wrap'
 
 module ActionView
   class TemplateRenderer < AbstractRenderer #:nodoc:
-    def render(options)
+    def render(context, options)
+      @view = context
+
       wrap_formats(options[:template] || options[:file]) do
         template = determine_template(options)
         freeze_formats(template.formats, true)
@@ -18,7 +20,7 @@ module ActionView
       if options.key?(:text)
         Template::Text.new(options[:text], formats.try(:first))
       elsif options.key?(:file)
-        with_fallbacks { find_template(options[:file], options[:prefixes], false, keys) }
+        with_fallbacks { find_template(options[:file], nil, false, keys) }
       elsif options.key?(:inline)
         handler = Template.handler_for_extension(options[:type] || "erb")
         Template.new(options[:inline], "inline template", handler, :locals => keys)
@@ -46,7 +48,7 @@ module ActionView
 
       if layout
         view = @view
-        view._view_flow.set(:layout, content)
+        view.view_flow.set(:layout, content)
         layout.render(view, locals){ |*name| view._layout_for(*name) }
       else
         content
diff --git a/actionpack/lib/action_view/rendering.rb b/actionpack/lib/action_view/rendering.rb
deleted file mode 100644
index 2bce2fb045..0000000000
--- a/actionpack/lib/action_view/rendering.rb
+++ /dev/null
@@ -1,114 +0,0 @@
-require 'active_support/core_ext/object/try'
-
-module ActionView
-  # = Action View Rendering
-  module Rendering
-    # Returns the result of a render that's dictated by the options hash. The primary options are:
-    #
-    # * <tt>:partial</tt> - See ActionView::Partials.
-    # * <tt>:file</tt> - Renders an explicit template file (this used to be the old default), add :locals to pass in those.
-    # * <tt>:inline</tt> - Renders an inline template similar to how it's done in the controller.
-    # * <tt>:text</tt> - Renders the text passed in out.
-    #
-    # If no options hash is passed or :update specified, the default is to render a partial and use the second parameter
-    # as the locals hash.
-    def render(options = {}, locals = {}, &block)
-      case options
-      when Hash
-        if block_given?
-          _render_partial(options.merge(:partial => options[:layout]), &block)
-        elsif options.key?(:partial)
-          _render_partial(options)
-        else
-          _render_template(options)
-        end
-      else
-        _render_partial(:partial => options, :locals => locals)
-      end
-    end
-
-    # Render but returns a valid Rack body. If fibers are defined, we return
-    # a streaming body that renders the template piece by piece.
-    #
-    # Note that partials are not supported to be rendered with streaming,
-    # so in such cases, we just wrap them in an array.
-    def render_body(options)
-      if options.key?(:partial)
-        [_render_partial(options)]
-      else
-        StreamingTemplateRenderer.new(self).render(options)
-      end
-    end
-
-    # Returns the contents that are yielded to a layout, given a name or a block.
-    #
-    # You can think of a layout as a method that is called with a block. If the user calls
-    # <tt>yield :some_name</tt>, the block, by default, returns <tt>content_for(:some_name)</tt>.
-    # If the user calls simply +yield+, the default block returns <tt>content_for(:layout)</tt>.
-    #
-    # The user can override this default by passing a block to the layout:
-    #
-    #   # The template
-    #   <%= render :layout => "my_layout" do %>
-    #     Content
-    #   <% end %>
-    #
-    #   # The layout
-    #   <html>
-    #     <%= yield %>
-    #   </html>
-    #
-    # In this case, instead of the default block, which would return <tt>content_for(:layout)</tt>,
-    # this method returns the block that was passed in to <tt>render :layout</tt>, and the response
-    # would be
-    #
-    #   <html>
-    #     Content
-    #   </html>
-    #
-    # Finally, the block can take block arguments, which can be passed in by +yield+:
-    #
-    #   # The template
-    #   <%= render :layout => "my_layout" do |customer| %>
-    #     Hello <%= customer.name %>
-    #   <% end %>
-    #
-    #   # The layout
-    #   <html>
-    #     <%= yield Struct.new(:name).new("David") %>
-    #   </html>
-    #
-    # In this case, the layout would receive the block passed into <tt>render :layout</tt>,
-    # and the struct specified would be passed into the block as an argument. The result
-    # would be
-    #
-    #   <html>
-    #     Hello David
-    #   </html>
-    #
-    def _layout_for(*args)
-      name = args.first
-      name = :layout unless name.is_a?(Symbol)
-      @_view_flow.get(name).html_safe
-    end
-
-    # Handle layout for calls from partials that supports blocks.
-    def _block_layout_for(*args, &block)
-      name = args.first
-
-      if !name.is_a?(Symbol) && block
-        capture(*args, &block)
-      else
-        _layout_for(*args)
-      end
-    end
-
-    def _render_template(options) #:nodoc:
-      _template_renderer.render(options)
-    end
-
-    def _template_renderer #:nodoc:
-      @_template_renderer ||= TemplateRenderer.new(self)
-    end
-  end
-end
diff --git a/actionpack/lib/action_view/template.rb b/actionpack/lib/action_view/template.rb
index 6dfc4f68ae..98ecd15aa0 100644
--- a/actionpack/lib/action_view/template.rb
+++ b/actionpack/lib/action_view/template.rb
@@ -139,15 +139,12 @@ module ActionView
     # we use a bang in this instrumentation because you don't want to
     # consume this in production. This is only slow if it's being listened to.
     def render(view, locals, buffer=nil, &block)
-      old_template, view._template = view._template, self
       ActiveSupport::Notifications.instrument("!render_template.action_view", :virtual_path => @virtual_path) do
         compile!(view)
         view.send(method_name, locals, buffer, &block)
       end
     rescue Exception => e
       handle_render_error(view, e)
-    ensure
-      view._template = old_template
     end
 
     def mime_type
@@ -174,12 +171,7 @@ module ActionView
     end
 
     def inspect
-      @inspect ||=
-        if defined?(Rails.root)
-          identifier.sub("#{Rails.root}/", '')
-        else
-          identifier
-        end
+      @inspect ||= defined?(Rails.root) ? identifier.sub("#{Rails.root}/", '') : identifier
     end
 
     protected
@@ -264,9 +256,9 @@ module ActionView
         # encoding of the code
         source = <<-end_src
           def #{method_name}(local_assigns, output_buffer)
-            _old_output_buffer = @output_buffer;#{locals_code};#{code}
+            _old_virtual_path, @virtual_path = @virtual_path, #{@virtual_path.inspect};_old_output_buffer = @output_buffer;#{locals_code};#{code}
           ensure
-            @output_buffer = _old_output_buffer
+            @virtual_path, @output_buffer = _old_virtual_path, _old_output_buffer
           end
         end_src
 
diff --git a/actionpack/lib/action_view/test_case.rb b/actionpack/lib/action_view/test_case.rb
index 5c74bf843a..d0317a148b 100644
--- a/actionpack/lib/action_view/test_case.rb
+++ b/actionpack/lib/action_view/test_case.rb
@@ -1,4 +1,6 @@
 require 'active_support/core_ext/object/blank'
+require 'active_support/core_ext/module/delegation'
+require 'active_support/core_ext/module/remove_method'
 require 'action_controller'
 require 'action_controller/test_case'
 require 'action_view'
@@ -43,6 +45,7 @@ module ActionView
       include AbstractController::Helpers
       include ActionView::Helpers
 
+      delegate :lookup_context, :to => :controller
       attr_accessor :controller, :output_buffer, :rendered
 
       module ClassMethods
@@ -127,7 +130,7 @@ module ActionView
 
       def say_no_to_protect_against_forgery!
         _helpers.module_eval do
-          remove_method :protect_against_forgery? if method_defined?(:protect_against_forgery?)
+          remove_possible_method :protect_against_forgery?
           def protect_against_forgery?
             false
           end
@@ -147,9 +150,19 @@ module ActionView
       module Locals
         attr_accessor :locals
 
-        def _render_partial(options)
-          locals[options[:partial]] = options[:locals]
-          super(options)
+        def render(options = {}, local_assigns = {})
+          case options
+          when Hash
+            if block_given?
+              locals[options[:layout]] = options[:locals]
+            elsif options.key?(:partial)
+              locals[options[:partial]] = options[:locals]
+            end
+          else
+            locals[options] = local_assigns
+          end
+
+          super
         end
       end