I discovered this in the rails migrations code here: https://github.com/rails/rails/blob/v3.2.13/activerecord/lib/active_record/migration.rb#L625
I think most people wouldn't see this, but I was also using the marginalia gem, which makes insanely deep stacks (apparently), so I was actually seeing this as a stack level too deep error.
My temporary work around was to remove marginalia from my Gemfile.
Fixes #1153. Dir should accept zero arguments