Re: RFC: adding pytest as a supported test framework

On Wed, Jun 12, 2024 at 7:08 PM Jelte Fennema-Nio <postgres(at)jeltef(dot)nl> wrote:
> On Wed, 12 Jun 2024 at 17:50, Andres Freund <andres(at)anarazel(dot)de> wrote:
> > > The OAuth pytest suite makes extensive use of
> > > - psycopg, to easily drive libpq;
> >
> > That's probably not going to fly. It introduces painful circular dependencies
> > between building postgres (for libpq), building psycopg (requiring libpq) and
> > testing postgres (requiring psycopg).
> >
> > You *can* solve such issues, but we've debated that in the past, and I doubt
> > we'll find agreement on the awkwardness it introduces.
>
> psycopg has a few implementations binary, c, & pure python. The pure
> python one can be linked to a specific libpq.so file at runtime[1]. As
> long as we don't break the libpq API (which we shouldn't), we can just
> point it to the libpq compiled by meson/make. We wouldn't be able to
> use the newest libpq features that way (because psycopg wouldn't know
> about them), but that seems totally fine for most usages (i.e. sending
> a query over a connection). If we really want to use those from the
> python tests we could write our own tiny CFFI layer specifically for
> those.

I guess you mean pg8000. Note that pg8000 and psycopg2 have some
differences in interpretation of datatypes (AFAIR arrays, jsonb...).
So, it would be easier to chose one particular driver. However, with
a bit efforts it's possible to make all the code driver agnostic.

------
Regards,
Alexander Korotkov
Supabase