Subject: Re: [PATCH v3 7/7] documentation: format-patch: clarify requirements for patch-ids to match

From: Junio C Hamano <[email-masked]>
Date: Mon, 17 Oct 2022 08:18:56 -0700

"Jerry Zhang via GitGitGadget" <[email-masked]> writes:

>  The 'base commit' is shown as "base-commit: " followed by the 40-hex of
>  the commit object name.  A 'prerequisite patch' is shown as
>  "prerequisite-patch-id: " followed by the 40-hex 'patch id', which can
> -be obtained by passing the patch through the `git patch-id --stable`
> -command.
> +be obtained by passing the patch (generated with -U3 --full-index) through
> +the `git patch-id --stable` command.

This is not incorrect per-se, but I wonder how much it would help or
mislead people in practice.

I understand that the update means well to help those who complain
"'patch-id' produces wrong result when I feed the output of 'git
diff -U1'" by making them suspect that their -U1 may be the culprit.
But the new description does not cover everything that can affect
the resulting patch ID (the choice of --diff-algorithm affects how
common lines are matched up between the preimage and the postimage,
for example).

So, I dunno.