Re: Injection points: some tools to wait and wake

On Wed, 6 Mar 2024 at 07:17, Michael Paquier <michael(at)paquier(dot)xyz> wrote:
> I'm open to that if there's enough demand for it, but I
> don't know how much we should accomodate with the existing
> requirements of contrib/ for something that's only developer-oriented.

There's quite a few developer-oriented GUCs as well, even requiring
their own DEVELOPER_OPTIONS section. So I don't think it's too weird
to have some developer-oriented extensions too.

> I'm not sure about that yet, TBH. Anything that gets added to this
> module should be used in some way by the in-core tests, or just not be
> there. That's a line I don't want to cross, which is why it's a test
> module.

That seems fine, if people need more functionality they can indeed
create their own test helpers. It mainly seems annoying for people to
have to copy-paste the ones from core to their own extension.

What I mainly meant is that anything in src/test/modules is not even
close to somewhat useful for other people to use. They are really just
very specific tests that need to be written in C. Afaict all those
modules are not even used by tests outside of their own module. But
these functions are helper functions, to be used by other tests. And
limiting the users of those helper functions to just be in-core
Postgres code seems a bit annoying. I feel like these functions are
more akin to the pgregress/isolationtester binaries in their usage,
than akin to other modules in src/test/modules.

> FWIW, it would be really annoying to have documentation
> requirements, actually, because that increases maintenance and I'm not
> sure it's a good idea to add a module maintenance on top of what could
> require more facility in the module to implement a test for a bug fix.

Quite a few contrib modules have very limited documentation. I think
it would be fine for this as well.

> This should just need -Dinjection_points=true.

Ugh... Sorry... I didn't realize that it needed a dedicated configure
flag. When providing that flag it indeed installs the expected files.
I guess that rules out testing against PGDG packages, because those
packages almost certainly wouldn't specify this flag.