Unclear warning before removing critical packages

Confirming. The current implementation of warning which packages will be removed returns incomplete lists.

gdebi-gtk does warn about removing ubuntu-desktop and libsdl1.2-debian-pulseaudio. However, software center does NOT warn that it's going to do autoremove and start removing their dependencies too.

I have just tried this in Natty alpha.
If you try and uninstall Cups you get the following message.
"If you uninstall Cups, future updates will not include new items in The Desktop system set. Ar you sure you want to continue."
And if you scroll down the bottom item on the list is "The Ubuntu desktop system"
If you continue you get a system that will not even boot into a command line.
I feel this bug should not be about changing the warning, although that needs doing, but should be about not removing the bulk of the Ubuntu system, for no good reason.
I understand, although I have not tried it, apt-get will get this right and remove cups and leave the system working.

I guess "The Ubuntu desktop system" is the ubuntu-desktop package. I'm glad Natty warns before removing that. Obviously the warning should be more strong considering the effect of continuing.

I had thought this sort of thing was caused by APT's dependency calculation going weird, so the same thing would happen whether you used apt-get or a GUI. It may vary by case though. Although it would the the better way, fixing a problem in APT would be more difficult than slapping a stronger warning on Software Center. Either way, something needs fixing. :-)

The error message David quotes is defined in step 4 of <https://wiki.ubuntu.com/SoftwareCenter#removing>. However, "The Ubuntu desktop system" is the title of ubuntu-desktop, and that is supposed to be special-cased with its own error message in step 3. So, that much is a bug in USC.

Removing ubuntu-desktop has no immediate effect, because it's just a metapackage. If there is an identifiable set of packages where removing any one of them prevents Ubuntu from starting up, there should be a separate bug report for USC to warn more strongly in that case.

If I understand you correctly, Matthew, we have a couple of problems.
 1) This message fails to appear when a dependency of ubuntu-desktop is marked for removal: “{title} is a core item in Ubuntu. Removing it may cause future upgrades to be incomplete.”
 2) When a very important package is marked for removal, the user isn't very strongly warned that it's a bad idea.

> If there is an identifiable set of packages where removing any one of them prevents Ubuntu from starting up, there should be a separate bug report for USC to warn more strongly in that case.

Perhaps someone can suggest a way to identify such packages. In my duplicate Bug #653293, I suggested simply hard-coding a list of important packages into USC. It's not pretty, but it's better than what's in place now.

Should these bugs be unmarked as duplicates since we have two issues to be addressed?

I removed evolution-data-server and evolution-data-server-common because I use gmail, so I didn't want any email software on my system. However, that removed gnome-panel with no notice whatsoever.
I would like to suggest that we show what packages are being removed regardless of whether it's considered 'important'. A list of 'important' software could always be incomplete. If it's going to be removed I'd like to know about it under any circumstance.

I agree, USC should definitely let you know what packages are being removed. I had thought that it already did, but perhaps not. But I think it should go a step further for users who don't know what packages are important (my example in Bug #653293 had no idea what gnome-panel was) by giving them a stern warning before such packages are removed.

The next step, to make *this* bug fixable, is for someone to come up with a way where USC can tell that it is dangerous to remove libcamel1.2-14 but not dangerous to remove evolution.

Any omissions in the list of packages that will be removed should be a separate bug report, please.

The issue I described in the other bug
https://bugs.launchpad.net/ubuntu/+source/software-center/+bug/680385
was slightly different:
The problem was caused because software center did apt-get autoremove. The packages removed before the autoremove operation were not critical.

This bug was fixed in the package software-center - 5.5.1.1

---------------
software-center (5.5.1.1) raring; urgency=low

  * Fix FTBFS in the clean target by build-depending on python-dbus,
    python-aptdaemon, python-gi, python-xapian, and python-xdg.
 -- Adam Conrad <email address hidden> Wed, 28 Nov 2012 19:08:21 -0700