From: brian m. carlson <sandals@crustytoothpaste.net>
Date: Fri, 20 Feb 2026 23:29:17 GMT
Subject: Re: [PATCH v2 0/8] Specify hooks via configs
Message-ID: <aZjuTSopOMvwR4hQ@fruit.crustytoothpaste.net>
In-Reply-To: <20260218222352.55393-1-adrian.ratiu@collabora.com>

On 2026-02-18 at 22:23:44, Adrian Ratiu wrote:
> Hello everyone,
> 
> v2 addresses all feedback received in v1.
> 
> This series adds a new feature: the ability to specify commands to run
> for hook events via config entries (including shell commands).
> 
> So instead of dropping a shell script or a custom program in .git/hooks
> you can now tell git via config files to run a program or shell script
> (can be specified directly in the config) when you run hook "foo".
> 
> This also means you can setup global hooks to run in multiple repos via
> global configs and there's an option to disable them if necessary.
> 
> For simplicity, because this series is becoming rather big, hooks are
> still executed sequentially (.jobs == 1). Parallel execution is added
> in another patch series.

I'm interested in how you plan to make parallel execution work
gracefully.

We've already established that it's necessary to preserve stdout and
stderr (including wiring them up to the TTY) so as to not break
existing, widely deployed hooks, such as those in Git LFS.  That means
that to get parallel execution where the hooks don't write over each
other's output and fight for the terminal, you'd need to multiplex each
one, including providing a PTY if the appropriate descriptor already has
a terminal, such that the output is at the very least handled line by
line and ideally batched into per-hook chunks.  Is that the plan, or do
you plan to do it differently?

I ask because situations where the hook output is not handled gracefully
and hooks fight over output or where the existence of TTY on a file
descriptor is not preserved will result in bug reports and broken tests
for tools that use Git, which I think we'd all like to avoid.

Of course, that's not in this series, so it may not even be written yet,
but if it's not, then this is something to keep in mind for when it gets
submitted.
-- 
brian m. carlson (they/them)
Toronto, Ontario, CA