diff --git a/lib/factory_girl/linter.rb b/lib/factory_girl/linter.rb
index e40b7b8..876e3bc 100644
--- a/lib/factory_girl/linter.rb
+++ b/lib/factory_girl/linter.rb
@@ -84,7 +84,7 @@ module FactoryGirl
 
     def error_message
       lines = invalid_factories.map do |_factory, exceptions|
-        exceptions.map &:message
+        exceptions.map(&:message)
       end.flatten
 
       <<-ERROR_MESSAGE.strip