Subject: Re: [PATCH v11 0/2] [GSOC] trailer: add new .cmd config option

From: Junio C Hamano <[email-masked]>
Date: Wed, 21 Apr 2021 16:40:22 -0700

ZheNing Hu <[email-masked]> writes:

> I admit that your idea makes sense, but we actually have another requirement:
> Construct a trailer with an empty value.

It can be done with a different script given to .cmd, which would
say "exit 0" when allowing an empty string given as its input to
appear in the output.

I was reacting what the "count" example does, and found that
counting commits by all authors (that is what an empty string would
match when given to --author="") somewhat illogical in the context
of that example.

After all, these examples are to pique readers' interest by
demonstrating what the mechanism can do and how it can be used, and
for this feature, I think showing that

 (1) we can squelch the output from unasked-for execution;

 (2) we can reject --trailer=<key>:<value> when we do not like the
     given <value>;

 (3) we can insert the trailer with the value we compute (and it is
     OK for the computed result happens to be an empty string).

should be plenty sufficient.