Change link_to_function and button_to_function to (optionally) take an update_page block instead of a JavaScript string. Closes #4804.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4235 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 42 insertions, 5 deletions

diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index 79e1bd1040..33f6b2a80d 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Change link_to_function and button_to_function to (optionally) take an update_page block instead of a JavaScript string. Closes #4804. [zraii@comcast.net, Sam Stephenson]
+
 * Fixed that remote_form_for can leave out the object parameter and default to the instance variable of the object_name, just like form_for [DHH]
 
 * Modify routing so that you can say :require => { :method => :post } for a route, and the route will never be selected unless the request method is POST. Only works for route recognition, not for route generation. [Jamis Buck]
diff --git a/actionpack/lib/action_view/helpers/javascript_helper.rb b/actionpack/lib/action_view/helpers/javascript_helper.rb
index 93a6e700b3..86829c2738 100644
--- a/actionpack/lib/action_view/helpers/javascript_helper.rb
+++ b/actionpack/lib/action_view/helpers/javascript_helper.rb
@@ -1,4 +1,5 @@
 require File.dirname(__FILE__) + '/tag_helper'
+require File.dirname(__FILE__) + '/prototype_helper'
 
 module ActionView
   module Helpers
@@ -40,15 +41,26 @@ module ActionView
       unless const_defined? :JAVASCRIPT_PATH
         JAVASCRIPT_PATH = File.join(File.dirname(__FILE__), 'javascripts')
       end
+
+      include PrototypeHelper
       
       # Returns a link that'll trigger a JavaScript +function+ using the 
       # onclick handler and return false after the fact.
       #
+      # The +function+ argument can be omitted in favor of an +update_page+
+      # block, which evaluates to a string when the template is rendered
+      # (instead of making an Ajax request first).      
+      #
       # Examples:
       #   link_to_function "Greeting", "alert('Hello world!')"
-      #   link_to_function(image_tag("delete"), "if confirm('Really?'){ do_delete(); }")
-      def link_to_function(name, function, html_options = {})
+      #   link_to_function(image_tag("delete"), "if (confirm('Really?')) do_delete()")
+      #   link_to_function("Show me more", nil, :id => "more_link") do |page|
+      #     page[:details].visual_effect  :toggle_blind
+      #     page[:more_link].replace_html "Show me less"
+      #   end
+      def link_to_function(name, function = '', html_options = {}, &block)
         html_options.symbolize_keys!
+        function = update_page(&block) if block_given?
         content_tag(
           "a", name, 
           html_options.merge({ 
@@ -58,14 +70,22 @@ module ActionView
         )
       end
       
-      # Returns a link that'll trigger a JavaScript +function+ using the 
+      # Returns a button that'll trigger a JavaScript +function+ using the 
       # onclick handler.
       #
+      # The +function+ argument can be omitted in favor of an +update_page+
+      # block, which evaluates to a string when the template is rendered
+      # (instead of making an Ajax request first).      
+      #
       # Examples:
       #   button_to_function "Greeting", "alert('Hello world!')"
-      #   button_to_function "Delete", "if confirm('Really?'){ do_delete(); }")
-      def button_to_function(name, function, html_options = {})
+      #   button_to_function "Delete", "if (confirm('Really?')) do_delete()"
+      #   button_to_function "Details" do |page|
+      #     page[:details].visual_effect :toggle_slide
+      #   end
+      def button_to_function(name, function = '', html_options = {}, &block)
         html_options.symbolize_keys!
+        function = update_page(&block) if block_given?
         tag(:input, html_options.merge({ 
           :type => "button", :value => name, 
           :onclick => (html_options[:onclick] ? "#{html_options[:onclick]}; " : "") + "#{function};" 
diff --git a/actionpack/test/template/javascript_helper_test.rb b/actionpack/test/template/javascript_helper_test.rb
index f0a405fae3..d186d11dd5 100644
--- a/actionpack/test/template/javascript_helper_test.rb
+++ b/actionpack/test/template/javascript_helper_test.rb
@@ -31,8 +31,23 @@ class JavaScriptHelperTest < Test::Unit::TestCase
       link_to_function("Greeting", "alert('Hello world!')", :onclick => "confirm('Sanity!')")
   end
 
+  def test_link_to_function_with_rjs_block
+    html = link_to_function( "Greet me!" ) do |page|
+      page.replace_html 'header', "<h1>Greetings</h1>"
+    end
+    assert_dom_equal %(<a href="#" onclick="Element.update(&quot;header&quot;, &quot;&lt;h1&gt;Greetings&lt;/h1&gt;&quot;);; return false;">Greet me!</a>), html
+  end
+
+
   def test_button_to_function
     assert_dom_equal %(<input type="button" onclick="alert('Hello world!');" value="Greeting" />), 
       button_to_function("Greeting", "alert('Hello world!')")
   end
+
+  def test_button_to_function_with_rjs_block
+    html = button_to_function( "Greet me!" ) do |page|
+      page.replace_html 'header', "<h1>Greetings</h1>"
+    end
+    assert_dom_equal %(<input type="button" onclick="Element.update(&quot;header&quot;, &quot;&lt;h1&gt;Greetings&lt;/h1&gt;&quot;);;" value="Greet me!" />), html
+  end
 end