rails/rails — pull request #8441 by itzki (2012-12-06 19:54:07+00:00)
Title: Fix decorate_columns for finding only non-serialized columns

steps to reproduce:

Topic.serialize(:content)
Topic.select(:id).last

> NoMethodError: undefined method `type' for nil:NilClass
> activerecord/lib/active_record/attribute_methods/serialization.rb:63:in `type'