[bug#49981] wip: Introduce unit-tests.

[Mathieu Othacehe <othacehe@gnu.org>]

Hello Chris,

> Converting the tests themselves in to things that have to be put in the
> store to be run could make local development harder, and is a step
> towards making guix harder to package and distribute. As an example, it
> would probably be possible for the Debian package to continue running
> the tests, but I'd expect that having to run a guix-daemon just to be
> able to setup for the tests will make running them more difficult.

That's a valid objection. Regarding the "current-guix" package, it
builds the unit tests as a whole and it would be hard to extract
precisely the result of each individual test.

As almost everything else in Guix is somehow a derivation, it would be
easier for Cuirass to deal with the unit tests under that format. Maybe
we would need to find a way to be able to run them under the actual
form, as well as under a derivation format. This needs more thoughts
though, so I'll put that on hold.

Thanks for the feedback,

Mathieu