rails/rails — pull request #13300 by chancancode (2013-12-12 20:04:37+00:00)
Title: Added :nodoc: for `attribute_changed?` and `attribute_was` [ci skip]

These methods were made "public" in 47617ecd so that `method_missing`
can invoke them without going through `send`, but they aren't meant
for consumption from outside of Rails.

cc @tenderlove
fyi @senny