Re: [PATCH 2/2] send-email: don't needlessly abs_path() the core.hooksPath

From: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
To: Junio C Hamano <gitster@pobox.com>
Cc: git@vger.kernel.org, Johannes Sixt <j6t@kdbg.org>,
	Johannes Schindelin <johannes.schindelin@gmx.de>,
	Jonathan Nieder <jrnieder@gmail.com>,
	Robert Foss <robert.foss@linaro.org>
Subject: Re: [PATCH 2/2] send-email: don't needlessly abs_path() the core.hooksPath
Date: Tue, 25 May 2021 07:57:37 +0200	[thread overview]
Message-ID: <874kerny0e.fsf@evledraar.gmail.com> (raw)
In-Reply-To: <xmqqh7iripzg.fsf@gitster.g>

On Tue, May 25 2021, Junio C Hamano wrote:

> Ævar Arnfjörð Bjarmason  <avarab@gmail.com> writes:
>
>> In c8243933c74 (git-send-email: Respect core.hooksPath setting,
>> 2021-03-23) we started supporting core.hooksPath in "send-email". It's
>> been reported that on Windows[1] doing this by calling abs_path()
>> results in different canonicalizations of the absolute path.
>
> I see the author of that patch CC'ed; the change in question
> explains why we switched from "the hooks directory immediately under
> $repo->repo_path()" to "ask 'rev-parse --git-path hooks'", but it
> does not say why we call abs_path() on the result.  I guess that is
> because $repo->repo_path() has always been a result of applying the
> abs_path() function to something, so it was to safeguard the callers
> that expect an absolute path coming back from hooks_path?
>
> And that makes this change dubious, especially as a band-aid for a
> breakage immediately before the final release, doesn't it?  Are we
> convinced that the callers are OK with seeing sometimes relative
> paths?  Certainly the cases the tests J6t fixed are not negatively
> affected, but is that sufficient?  To what directory is the
> configuration variable supposed to be relative to, and are we sure
> that the user will always invoke "git send-email" from that
> directory?

The one caller is git-send-email.perl is fine with it, at least on *nix,
this fix still needs testing on Windows.

The repo_path() function was introduced in c8243933c74, so it's never
been in a release, thus I think it's fine to alter its behavior.

The code here doesn't need to concern itself with what needs to be
relative to what, you run send-email in some working tree directory (or
top-level), and depending on core.hooksPath we'll either return a
relative path to the .git/hooks or an absolute one, the system()
invocation will accept either.