Check if the logger exists before trying to use it

activerecord/lib/active_record/scoping/named.rb

@@ -174,7 +174,7 @@ def scope(name, body, &block)
       protected
 
         def valid_scope_name?(name)
-          if respond_to?(name, true)
+          if respond_to?(name, true) && logger
             logger.warn "Creating scope :#{name}. " \
                         "Overwriting existing method #{self.name}.#{name}."
           end