Move render_to_body logic to return a spaced string to AC::Rendering

This seems to be required only when calling render :partial with an
empty collection from a controller. This call happens to return no
content, letting the response body empty, which means to Rails that it
should go on and try to find a template to render based on the current
action name, thus failing hard.

Although tests keep all green, we need to check a better way to fix
this.

4 files changed, 5 insertions, 7 deletions

diff --git a/actionpack/lib/action_controller/metal/compatibility.rb b/actionpack/lib/action_controller/metal/compatibility.rb
index 96707b6587..813b6501d1 100644
--- a/actionpack/lib/action_controller/metal/compatibility.rb
+++ b/actionpack/lib/action_controller/metal/compatibility.rb
@@ -13,9 +13,5 @@ module ActionController
         :@_view_runtime, :@_stream, :@_url_options, :@_action_has_layout
       ]
     end
-
-    def render_to_body(options)
-      super || " "
-    end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/rendering.rb b/actionpack/lib/action_controller/metal/rendering.rb
index f6e9e4c4ac..a677cdf15d 100644
--- a/actionpack/lib/action_controller/metal/rendering.rb
+++ b/actionpack/lib/action_controller/metal/rendering.rb
@@ -29,6 +29,10 @@ module ActionController
       self.response_body = nil
     end
 
+    def render_to_body(*)
+      super || " "
+    end
+
     private
 
     # Normalize arguments by catching blocks and setting them on :update.
diff --git a/actionpack/lib/action_controller/metal/streaming.rb b/actionpack/lib/action_controller/metal/streaming.rb
index 0e46402962..e9783e6919 100644
--- a/actionpack/lib/action_controller/metal/streaming.rb
+++ b/actionpack/lib/action_controller/metal/streaming.rb
@@ -216,7 +216,7 @@ module ActionController #:nodoc:
       end
     end
 
-    # Call render_to_body if we are streaming instead of usual +render+.
+    # Call render_body if we are streaming instead of usual +render+.
     def _render_template(options) #:nodoc:
       if options.delete(:stream)
         Rack::Chunked::Body.new view_renderer.render_body(view_context, options)
diff --git a/actionpack/lib/action_view/test_case.rb b/actionpack/lib/action_view/test_case.rb
index c734c914db..b00f69e636 100644
--- a/actionpack/lib/action_view/test_case.rb
+++ b/actionpack/lib/action_view/test_case.rb
@@ -233,10 +233,8 @@ module ActionView
           super
         end
       end
-
     end
 
     include Behavior
-
   end
 end