1 files changed, 3 insertions, 3 deletions
diff --git a/actionpack/lib/action_dispatch/http/response.rb b/actionpack/lib/action_dispatch/http/response.rb
index fc840668d5..5797c63924 100644
--- a/actionpack/lib/action_dispatch/http/response.rb
+++ b/actionpack/lib/action_dispatch/http/response.rb
@@ -111,9 +111,9 @@ module ActionDispatch # :nodoc:
     end
 
     def body
-      str = ''
-      each { |part| str << part.to_s }
-      str
+      strings = []
+      each { |part| strings << part.to_s }
+      strings.join
     end
 
     EMPTY = " "