Bug#579522: tasksel - Removes packages without consent

[Serafeim Zanikolas <sez@debian.org>]

On Sun, Oct 31, 2010 at 11:52:39AM +0100, Serafeim Zanikolas wrote:
> Hi,
> 
> I see two approaches here. Run aptitude in simulation mode, parse the output,
> and ask for user confirmation if any removals are required.
> 
> Alternatively, tweak aptitude to not install any packages that require
> removals. I don't know or use aptitude but from the little I've looked into
> the manual, it looks that the default setting for
> Aptitude::ProblemResolver::{Safe-Level,Resolver::Remove-Level} is already set
> to the safest value (10000). Perhaps I've missed a way to just say "don't
> install packages that require removals" (but wouldn't that defeat the whole
> point of tasksel?)

So -o Aptitude::ProblemResolver::Remove-Level=maximum seems to do the trick,
at the expense of not installing many of the package(s) that should normally
be installed for the selected task.

On my box:

    aptitude -s -y install desktop gnome-desktop

has to remove swfdec-mozilla because

   epiphany-browser: Conflicts: swfdec-mozilla but 0.8.8-5 is installed.

and results to:

    0 packages upgraded, 468 newly installed, 1 to remove and 21 not upgraded.


With Aptitude::ProblemResolver::Remove-Level=maximum, the picture is very
different:

    0 packages upgraded, 375 newly installed, 0 to remove and 21 not upgraded.

As I wrote already, I see this as defeating the point of tasksel, and would
suggest the first approach (run aptitude in simulation mode, and ask user
confirmation about pending pkgs removal).

-S