Re: [PATCH 2/2] pretty: add '%aA' to show domain-part of email addresses

[Liam Beguin <liambeguin@gmail.com>]

Hi Junio, Peff,

On Fri, Oct 27, 2023 at 10:13:01PM -0400, Jeff King wrote:
> On Sat, Oct 28, 2023 at 09:12:06AM +0900, Junio C Hamano wrote:
> 
> > Grouping @gmail.com addresses do not smell all that useful, though.

While I agree with you, I think that's more an exception that the rule.

> > More importantly, it is not clear what "Many reports" refers to.  If
> > they are *not* verbatim output from "git log" family of commands,
> > iow, they are produced by post-processing output from "git log"
> > family of commands, then I do not quite see why %aa is useful at
> > all.

I might've been a bit generous with "many report", I was mostly thinking
of the ones published by lwn.net, and U-Boot for example.

To some extent, "git shortlog" could be considered a part of that
post-processing chain.

> One way you could directly use this is in shortlog, which these days
> lets you group by specific formats. So:
> 
>   git shortlog -ns --group=format:%aA

That's exactly what I implemented this for :-)

> is potentially useful.
> 
> I say "potentially" because it really depends on your project and its
> contributors. In git.git the results are mostly either too broad
> ("gmail.com" covers many unrelated people) or too narrow (I'll assume
> I'm the only contributor from "peff.net"). There are a few possibly
> useful ones ("microsoft.com", "gitlab.com", though even those are
> misleading because email domains don't always correspond to
> affiliations).

I agree with your comment here, while grouping everything under
"gmail.com" for example doesn't provide anything really useful we can
rely on mailmap to fix that when appropriate. I think it would otherwise
count as unaffiliated.

I don't claim this to be foolproof, but I do think that it gives a good
overall view of which companies are involved in the project for the most
part.

> So I don't find it useful myself, but I see how it could be in the right
> circumstances. It also feels like a symmetric match to "%al", which
> already exists. I do find "aa" as the identifier a little hard to
> remember. I guess it's "a" for "address", though I'd have called the
> whole local@domain thing an address thing that. Of course "d" for domain
> would make sense, but that is already taken. If we could spell it as
> %(authoremail:domain) that would remove the question. But given the
> existence of "%al", I'm not too sad to see another letter allocated to
> this purpose in the meantime.

I chose the "a" for "address", but I'm not sold on %aa either.
I just couldn't find anything better that wasn't already taken.

What about "a@"?

It's a bit easier to remember, being the first character of the
domain-part.

> Just my two cents as a shortlog --format afficionado. ;) (Of course,
> shortlog itself is the ultimate "you could really just post-process log
> output" example).

I'm a big fan of shortlog --format (and --group) as well!

Taking it a step further, it's also possible to pass in whatever mailmap
you want to generate a "report".  Let's say there's mapping that only
makes sense for a single release something like this could be used:

git -c mailmap.file=git-mailmap-v2.42 shortlog -sn --group=format:%aA

> -Peff

Thanks for your time.

Cheers,
Liam