Re: [PATCH v3 5/5] add -p: ignore dirty submodules

From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Aug 31, 2022, 20:38 UTC
Message-ID: <q77sq7pn-n473-p12s-po5o-6970rr884528@tzk.qr>
In-Reply-To: <xmqqr10wdv4b.fsf@gitster.g>

Hi Junio,

On Wed, 31 Aug 2022, Junio C Hamano wrote:

Show 12 quoted lines

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
>
> > And it is that doubling of work that I tried to avoid when implementing
> > the built-in version. The bug came about because the full diff call wasn't
> > using the `--ignore-submodules=dirty` option, and that's what I missed.
> >
> > This is maybe more interesting a story for the cover letter, to be able to
> > understand how this bug was introduced, and maybe to offer an opportunity
> > for others (in addition to myself) to learn from my mistake.
>
> Yup, the moral of the story is premature optimization bites because
> we are not always careful ;-)

Yes. Maybe even more generally: trying to do too many things at once is prone to introduce bugs.

> Anyhow, I am getting an impression that the behaviour of the next
> iteration would be much closer to the original, which is excellent.

Yep!

> We have seen too many "ah, this is broken and here is a fix that is
> appropriate in the context of how the new C version does it", not
> "ok, let's make the whole thing behave more like what we used to
> have".

Unfortunately so.

It is a fine line, and not always possible to tread safely, between trying to stay close to the original and trying to learn the lesson from Elijah that converting scripts to C without playing to C's strengths causes a lot of hiccups later on. There are probably better alternatives for prototyping Git functionality than using either an untyped language that cannot hold complex data structures in memory or a language to which everything looks like a map ;-)

Ciao, Dscho