Bug#1001173: Moo: Should use Depends for libclass-xsaccessor-perl (instead of Recoomends)

[Graham Knop]

On Sun, 05 Dec 2021 19:09:38 +0100 intrigeri <intrigeri at debian.org> wrote:
> Hi,
>
> Felix Lechner (2021-12-05):
> > Moo performs faster when Class::XSAccessor is available [1] but
> > libmoo-perl only Recommends it. More important, Moo's behavior changes
> > when Class::XSAccessor is installed. [1]  For consistency as well as
> > performance, Moo should probably Depend on libclass-xsaccessor-perl.
> >
> > While a new, hard prerequisite may cause some programs using Moo to
> > fail unexpectedly, they would at least do so consistently. It would
> > eliminate a transient class of bugs that depends on whether
> > Class::XSAccessor is present on a reporter's system—something that can
> > be hard to pin down when the installable is only recommended.
>
> I agree with your reasoning.
>
> I'm 90% convinced we should do this but I'd first like to understand
> why upstream chose to only recommend Class::XSAccessor: their
> reasoning might make sense for us too :)
>
> Would you mind asking upstream about this?

I'm the maintainer of Moo.

The reason Class::XSAccessor isn't listed as a hard prerequisite is
that Moo is intended to be compatible with systems without a compiler
available. Since XS modules require a compiler, Moo does not have any
non-core hard dependencies that use XS. When packaging for Debian (or
any other dist) it would be entirely reasonable to list it as a hard
prereq.