1 files changed, 19 insertions, 6 deletions
diff --git a/actionpack/lib/action_view/renderer/partial_renderer.rb b/actionpack/lib/action_view/renderer/partial_renderer.rb
index 245a19deec..8b53867aea 100644
--- a/actionpack/lib/action_view/renderer/partial_renderer.rb
+++ b/actionpack/lib/action_view/renderer/partial_renderer.rb
@@ -32,7 +32,7 @@ module ActionView
   #
   #   <%= render :partial => "account", :object => @buyer %>
   #
-  # would provide the +@buyer+ object to the partial, available under the local variable +account+ and is
+  # would provide the <tt>@buyer</tt> object to the partial, available under the local variable +account+ and is
   # equivalent to:
   #
   #   <%= render :partial => "account", :locals => { :account => @buyer } %>
@@ -245,18 +245,25 @@ module ActionView
   #     <%- end -%>
   #   <% end %>
   class PartialRenderer < AbstractRenderer
-    PARTIAL_NAMES = Hash.new { |h,k| h[k] = {} }
+    PREFIXED_PARTIAL_NAMES = Hash.new { |h,k| h[k] = {} }
 
     def initialize(*)
       super
       @context_prefix = @lookup_context.prefixes.first
-      @partial_names = PARTIAL_NAMES[@context_prefix]
     end
 
     def render(context, options, block)
       setup(context, options, block)
       identifier = (@template = find_partial) ? @template.identifier : @path
 
+      @lookup_context.rendered_format ||= begin
+        if @template && @template.formats.present?
+          @template.formats.first
+        else
+          formats.first
+        end
+      end
+
       if @collection
         instrument(:collection, :identifier => identifier || "collection", :count => @collection.size) do
           render_collection
@@ -316,8 +323,6 @@ module ActionView
       @block   = block
       @details = extract_details(options)
 
-      @lookup_context.rendered_format ||= formats.first
-
       if String === partial
         @object     = options[:object]
         @path       = partial
@@ -417,7 +422,15 @@ module ActionView
         raise ArgumentError.new("'#{object.inspect}' is not an ActiveModel-compatible object. It must implement :to_partial_path.")
       end
 
-      @partial_names[path] ||= merge_prefix_into_object_path(@context_prefix, path.dup)
+      if @view.prefix_partial_path_with_controller_namespace
+        prefixed_partial_names[path] ||= merge_prefix_into_object_path(@context_prefix, path.dup)
+      else
+        path
+      end
+    end
+
+    def prefixed_partial_names
+      @prefixed_partial_names ||= PREFIXED_PARTIAL_NAMES[@context_prefix]
     end
 
     def merge_prefix_into_object_path(prefix, object_path)