Merge remote-tracking branch 'upstream/master'

1 files changed, 10 insertions, 1 deletions

diff --git a/actionpack/lib/action_view/template/handlers/builder.rb b/actionpack/lib/action_view/template/handlers/builder.rb
index 2c52cfd90e..34397c3bcf 100644
--- a/actionpack/lib/action_view/template/handlers/builder.rb
+++ b/actionpack/lib/action_view/template/handlers/builder.rb
@@ -6,12 +6,21 @@ module ActionView
       self.default_format = Mime::XML
 
       def call(template)
-        require 'builder'
+        require_engine
         "xml = ::Builder::XmlMarkup.new(:indent => 2);" +
           "self.output_buffer = xml.target!;" +
           template.source +
           ";xml.target!;"
       end
+
+      protected
+
+      def require_engine
+        @required ||= begin
+          require "builder"
+          true
+        end
+      end
     end
   end
 end