Re: Bug#758234: transitive dependencies

[Simon McVittie <smcv@debian.org>]

On 13/11/14 12:34, Bill Allombert wrote:
> For me priority are purely metadata provided by the override file.
> Policy does not require software to use them in anyway, I think.

Policy does not require software to use them; but in practice, software
does use them, and so changing a Priority has observable side-effects.
For instance, debootstrap will install Priority >= important by default,
and Priority >= required always, except where packages are specifically
excluded.

One concrete effect of the current priority-inheritance is that
"debootstrap --exclude=aptitude" will unnecessarily install libxapian22,
libboost-iostreams1.55.0 and other aptitude dependencies.

If you believe that they are just informative metadata like the Section
or Description, and that software should not do things like "install all
packages of Priority >= important" any more than it would do things like
"install everything from Section: python", then we need a different way
for debootstrap and d-i to decide what the base system is, perhaps a
metapackage.

Also, the current process for maintaining them, and in particular the
requirement to keep transitive priorities consistent, seems rather more
heavyweight than would be justified by them being purely informative.

    S