Use File.join to construct partial path. Closes #10932 [patrick.t.joyce]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8739 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

actionpack/lib/action_view/partials.rb

@@ -107,17 +107,18 @@ def render_partial(partial_path, object_assigns = nil, local_assigns = nil) #:no
         case partial_path
         when String, Symbol, NilClass
           path, partial_name = partial_pieces(partial_path)
+          full_partial_path = File.join(path, "_#{partial_name}")
           object = extracting_object(partial_name, object_assigns)
           local_assigns = local_assigns ? local_assigns.clone : {}
           add_counter_to_local_assigns!(partial_name, local_assigns)
           add_object_to_local_assigns!(partial_name, local_assigns, object)
 
           if logger && logger.debug?
-            ActionController::Base.benchmark("Rendered #{path}/_#{partial_name}", Logger::DEBUG, false) do
-              render("#{path}/_#{partial_name}", local_assigns)
+            ActionController::Base.benchmark("Rendered #{full_partial_path}", Logger::DEBUG, false) do
+              render(full_partial_path, local_assigns)
             end
           else
-            render("#{path}/_#{partial_name}", local_assigns)
+              render(full_partial_path, local_assigns)
           end
         when ActionView::Helpers::FormBuilder
           builder_partial_path = partial_path.class.to_s.demodulize.underscore.sub(/_builder$/, '')