render every partial with a new `PartialRenderer`.

This resolves issues when rendering nested partials.
Previously the `PartialRenderer` was reused which led to
situations where the state of the renderer was reset.

Closes #8197

3 files changed, 18 insertions, 2 deletions

diff --git a/actionpack/CHANGELOG.md b/actionpack/CHANGELOG.md
index 1ebc75ed2f..0f1e1f303f 100644
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
@@ -1,5 +1,11 @@
 ## Rails 4.0.0 (unreleased) ##
 
+*   Render every partial with a new `ActionView::PartialRenderer`. This resolves
+    issues when rendering nested partials.
+    Fix #8197
+
+    *Yves Senn*
+
 *   Introduce `ActionView::Template::Handlers::ERB.escape_whitelist`. This is a list
     of mime types where template text is not html escaped by default. It prevents `Jack & Joe`
     from rendering as `Jack & Joe` for the whitelisted mime types. The default whitelist
diff --git a/actionpack/lib/action_view/renderer/renderer.rb b/actionpack/lib/action_view/renderer/renderer.rb
index bf1b5a7d22..dfef43bc9d 100644
--- a/actionpack/lib/action_view/renderer/renderer.rb
+++ b/actionpack/lib/action_view/renderer/renderer.rb
@@ -44,11 +44,11 @@ module ActionView
     private
 
     def _template_renderer #:nodoc:
-      @_template_renderer ||= TemplateRenderer.new(@lookup_context)
+      TemplateRenderer.new(@lookup_context)
     end
 
     def _partial_renderer #:nodoc:
-      @_partial_renderer ||= PartialRenderer.new(@lookup_context)
+      PartialRenderer.new(@lookup_context)
     end
   end
 end
diff --git a/actionpack/test/controller/render_test.rb b/actionpack/test/controller/render_test.rb
index aa33f01d02..859ed1466b 100644
--- a/actionpack/test/controller/render_test.rb
+++ b/actionpack/test/controller/render_test.rb
@@ -646,6 +646,10 @@ class TestController < ActionController::Base
     render :partial => "customer", :spacer_template => "partial_only", :collection => [ Customer.new("david"), Customer.new("mary") ]
   end
 
+  def partial_collection_with_spacer_which_uses_render
+    render :partial => "customer", :spacer_template => "partial_with_partial", :collection => [ Customer.new("david"), Customer.new("mary") ]
+  end
+
   def partial_collection_shorthand_with_locals
     render :partial => [ Customer.new("david"), Customer.new("mary") ], :locals => { :greeting => "Bonjour" }
   end
@@ -1445,6 +1449,12 @@ class RenderTest < ActionController::TestCase
     assert_template :partial => '_customer'
   end
 
+  def test_partial_collection_with_spacer_which_uses_render
+    get :partial_collection_with_spacer_which_uses_render
+    assert_equal "Hello: davidpartial html\npartial with partial\nHello: mary", @response.body
+    assert_template :partial => '_customer'
+  end
+
   def test_partial_collection_shorthand_with_locals
     get :partial_collection_shorthand_with_locals
     assert_equal "Bonjour: davidBonjour: mary", @response.body