Bug 474704

Sometimes you need to perform a major package layout restructuring. As in, you need to replace a pool of packages with another pool of packages, with totally different provides and package splits.

Since you can not do many to many obsoleting, one way to achieve this is a transition metapackage:

1. You create your new pool of packages with their internal dependencies, etc relations as if no past existed (clean new state)

2. You add a special empty package or subpackage that obsoletes all the packages in the old pool, and requires all the packages in the new pool you want installed by default for upgraded systems

3. You hide this special package from new users, and let them select packages normally

This is sufficient to garbage-collect the old package pool and get everyone (new installs and upgrades) in the new state. Victory!

Unfortunately, you still have your garbage-collecting metapackage installed on upgraded system. It really has no point anymore, but you can not obsolete it with one of your new long-term packages till you're sure every user of the old pool has migrated (or your break your upgrade path). And at the same time, the longer you keep it available the longer you risk one of your fellow packagers decides to add a dep on it because that's easier than trying to understand the awesomeness of your new package pool.

It would be great if it was possible to add a flag to this package that basically told rpm "remove this package just after installation, it has served its purpose, do not keep it".