Datamapper DataMapper

I noticed an interesting behavior while working on a program of mine which needs to load additional STIed models after the database has been setup/auto-upgraded, and then auto-upgrade the repository a second time. It appears that by defining new classes that inherit from STI base-classes, after the initial auto-upgrade has been executed, subsequent auto-upgrades fail to properly upgrade the tables for the STI base-classes.

A recreation of the bug is available here:
http://gist.github.com/121233

ruby dm_sti_auto_upgrade_bug.rb
sqlite3 ./test.db
.dump
.quit

As you can see the Admin model inherits from the User model, and defines an additional :group_id foreign key. After running the above mentioned script and inspecting the sqlite3 database, no :group_id key was added to the users table; although the groups table was created.

I did notice that if I defined all of the STI classes before the initial auto_upgrade, all defined properties would be upgraded in the repository. I believe that subsequent auto-upgrades should have the same effect as the initial one.