Filter params that return nil for to_param and allow through false values

actionpack/CHANGELOG

 *Rails 3.1.0 (unreleased)*
 
+* URL parameters which return false for to_param now appear in the query string (previously they were removed) [Andrew White]
+
+* URL parameters which return nil for to_param are now removed from the query string [Andrew White]
+
 * ActionDispatch::MiddlewareStack now uses composition over inheritance. It is
 no longer an array which means there may be methods missing that were not
 tested.

actionpack/lib/action_dispatch/http/url.rb

@@ -41,7 +41,7 @@ def url_for(options = {})
           path = options.delete(:path) || ''
 
           params = options[:params] || {}
-          params.reject! {|k,v| !v }
+          params.reject! {|k,v| v.to_param.nil? }
 
           rewritten_url << (options[:trailing_slash] ? path.sub(/\?|\z/) { "/" + $& } : path)
           rewritten_url << "?#{params.to_query}" unless params.empty?

actionpack/lib/action_view/helpers/prototype_helper.rb

@@ -131,7 +131,6 @@ def remote_function(options)
           "new Ajax.Updater(#{update}, "
 
         url_options = options[:url]
-        url_options = url_options.merge(:escape => false) if url_options.is_a?(Hash)
         function << "'#{ERB::Util.html_escape(escape_javascript(url_for(url_options)))}'"
         function << ", #{javascript_options})"
 

actionpack/test/controller/url_for_test.rb

@@ -311,6 +311,14 @@ def test_with_hash_with_indifferent_access
         assert_equal("/c/a", W.new.url_for(HashWithIndifferentAccess.new('controller' => 'c', 'action' => 'a', 'only_path' => true)))
       end
 
+      def test_url_params_with_nil_to_param_are_not_in_url
+        assert_equal("/c/a", W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :id => Struct.new(:to_param).new(nil)))
+      end
+
+      def test_false_url_params_are_included_in_query
+        assert_equal("/c/a?show=false", W.new.url_for(:only_path => true, :controller => 'c', :action => 'a', :show => false))
+      end
+
       private
         def extract_params(url)
           url.split('?', 2).last.split('&').sort