Add the ability to call JavaScriptGenerator methods from helpers called in update blocks

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3470 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 61 insertions, 16 deletions

diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index bf00979083..7476c736ac 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,19 @@
 *SVN*
 
+* Add the ability to call JavaScriptGenerator methods from helpers called in update blocks. [Sam Stephenson]  Example:
+  module ApplicationHelper
+    def update_time
+      page.replace_html 'time', Time.now.to_s(:db)
+      page.visual_effect :highlight, 'time'
+    end
+  end
+
+  class UserController < ApplicationController
+    def poll
+      render :update { |page| page.update_time }
+    end
+  end
+
 * Fixed that SSL would not correctly be detected when running lighttpd/fcgi behind lighttpd w/mod_proxy #3548 [stephen_purcell@yahoo.com]
 
 * Added the possibility to specify atomatic expiration for the memcachd session container #3571 [Stefan Kaes]
diff --git a/actionpack/lib/action_controller/base.rb b/actionpack/lib/action_controller/base.rb
index 0a9368f684..7f8ff5ed09 100755
--- a/actionpack/lib/action_controller/base.rb
+++ b/actionpack/lib/action_controller/base.rb
@@ -687,7 +687,7 @@ module ActionController #:nodoc:
       end
 
       def render_javascript(javascript, status = nil)
-        @response.headers['Content-type'] = 'text/javascript'
+        @response.headers['Content-Type'] = 'text/javascript'
         render_text(javascript, status)
       end
 
@@ -719,7 +719,8 @@ module ActionController #:nodoc:
         @response.body = nil
         @performed_render = false
       end
-
+      
+      
       # Clears the redirected results from the headers, resets the status to 200 and returns 
       # the URL that was used to redirect or nil if there was no redirected URL
       # Note that +redirect_to+ will change the body of the response to indicate a redirection.
diff --git a/actionpack/lib/action_view/helpers/prototype_helper.rb b/actionpack/lib/action_view/helpers/prototype_helper.rb
index d35334a98c..edf6f50a06 100644
--- a/actionpack/lib/action_view/helpers/prototype_helper.rb
+++ b/actionpack/lib/action_view/helpers/prototype_helper.rb
@@ -370,34 +370,52 @@ module ActionView
       # this in your Ajax response bodies, either in a <script> tag or as plain
       # JavaScript sent with a Content-type of "text/javascript".
       #
-      # Create new instances with PrototypeHelper#update_page, then call 
-      # #insert_html, #replace_html, #remove, #show, or #hide on the yielded
-      # generator in any order you like to modify the content and appearance of
-      # the current page.  (You can also call other helper methods which
-      # return JavaScript, such as 
-      # ActionView::Helpers::ScriptaculousHelper#visual_effect.)
+      # Create new instances with PrototypeHelper#update_page or with 
+      # ActionController::Base#render, then call #insert_html, #replace_html, 
+      # #remove, #show, #hide, #visual_effect, or any other of the built-in 
+      # methods on the yielded generator in any order you like to modify the 
+      # content and appearance of the current page. 
       #
       # Example:
       #
       #   update_page do |page|
-      #     page.insert_html :bottom, 'list', '<li>Last item</li>'
+      #     page.insert_html :bottom, 'list', "<li>#{@item.name}</li>"
       #     page.visual_effect :highlight, 'list'
       #     page.hide 'status-indicator', 'cancel-link'
       #   end
       # 
       # generates the following JavaScript:
       #
-      #   new Insertion.Bottom("list", "<li>Last item</li>");
+      #   new Insertion.Bottom("list", "<li>Some item</li>");
       #   new Effect.Highlight("list");
       #   ["status-indicator", "cancel-link"].each(Element.hide);
       #
+      # Helper methods can be used in conjunction with JavaScriptGenerator.
+      # When a helper method is called inside an update block on the +page+ 
+      # object, that method will also have access to a +page+ object.
+      # 
+      # Example:
+      #
+      #   module ApplicationHelper
+      #     def update_time
+      #       page.replace_html 'time', Time.now.to_s(:db)
+      #       page.visual_effect :highlight, 'time'
+      #     end
+      #   end
+      #
+      #   # Controller action
+      #   def poll
+      #     render :update { |page| page.update_time }
+      #   end
+      #
       # You can also use PrototypeHelper#update_page_tag instead of 
       # PrototypeHelper#update_page to wrap the generated JavaScript in a
       # <script> tag.
       class JavaScriptGenerator
-        def initialize(context) #:nodoc:
+        def initialize(context, &block) #:nodoc:
           @context, @lines = context, []
-          yield self
+          include_helpers_from_context
+          @context.instance_exec(self, &block)
         end
   
         def to_s #:nodoc:
@@ -501,12 +519,24 @@ module ActionView
           yield
           record "}, #{(seconds * 1000).to_i})"
         end
-
+        
+        # Starts a Scriptaculous visual effect. See 
+        # ActionView::Helpers::ScriptaculousHelper for more information.
+        def visual_effect(name, id, options = {})
+          record ScriptaculousHelper::visual_effect(name, id, options)
+        end
+        
       private
-        def method_missing(method, *arguments, &block)
-          record(@context.send(method, *arguments, &block))
+        def include_helpers_from_context
+          @context.extended_by.each do |mod|
+            extend mod unless mod.name =~ /^ActionView::Helpers/
+          end
         end
-
+        
+        def page
+          self
+        end
+        
         def record(line)
           returning line = "#{line.to_s.chomp.gsub /\;$/, ''};" do
             self << line