Comment 42 for bug 342671

I updated the description of the bug sometime ago. It should provide a brief summary.

You have to make a difference for stable and development versions: It is very unlikely that a security update of a stable release will remove an already installed package. But this will happen quite often in the development version. Nevertheless it is a bug.

I already allowed updates to install further packages in Karmic, which required an advanced dependency resolver. (This is one of the issues that I improved for Karmic if you don't see any progress)

Another problem is the missing preview in the 0.4.x series of PackageKit: We cannot currently preview the removal of packages which would happen during an installation. So removing packages without notifying the user seems to be an even worse issue.

The missing PolicyKit-1 support in KDE blocks the 0.5.x series. In the 0.5.x series it is possible to preview "complex" transactions.

In contrast to Synaptic and aptitude PackageKit is transaction based. So you can queue actions instead of having to apply them once at the sametime. Secondly PackageKit has got a privilege separation: It is possible to have different privileges for installing/removing/updating packages or refreshing the cache.

So in the end this not a pure coding, but a convention and design issue of PackageKit. It would have to even remove some code to allow removal of packages during updates/installations.

I raised the issue once again on the mailing list.