Hey Mark,
On Mon, Aug 12 2019, Mark H Weaver wrote:
What leads you to believe this?
I think you're mistaken, based both on past experience and also
from examining the current code.
After taking another look at the code, I agree with you.
The relevant procedure is 'transaction-upgrade-entry' in (guix
scripts package), here:
https://git.savannah.gnu.org/cgit/guix.git/tree/guix/scripts/package.scm?id=c383c36edeb7eb358f142c52276d6e5d32bda044#n225
This is the code I was looking at, but I think I was just too
hasty when I looked at it. In the past I've seen conflicts similar
to what Andy saw, and was always able to resolve them easily by
using "guix package -i" rather than "guix package -u", from which
I formed my hypothesis about how --upgrade deals with versions.
This is certainly the behavior I remember from using --upgrade
myself during the early years of Guix, although in recent years
I've been using the declarative approach to maintain my profile,
using "guix package --manifest".
I have also switched to using --manifest, so my memories of
--upgrade aren't very strong.
Carlo