rails/rails — pull request #6524 by sskirby (2012-05-28 21:46:07+00:00)
Title: Identity map master

This is for #5261.

This pull request fixes the issue outlined in https://github.com/rails/rails/commit/302c912.

It takes the approach that bi-directional associations need to be kept in sync by the developer, not the framework. I believe that this is an acceptable approach and it is one that is commonly implemented by other ORMs such as Hibernate.