Re: Proposal: Remembering message IDs sent with git send-email

From: Emily Shaffer <emilyshaffer@google.com>
Date: May 9, 2019, 00:19 UTC
Message-ID: <20190509001959.GB14000@google.com>
In-Reply-To: <20190508231013.GA25216@homura.localdomain>

On Wed, May 08, 2019 at 07:10:13PM -0400, Drew DeVault wrote:

Show 5 quoted lines

> I want to gather some thoughts about this. Say you've written a patch
> series and are getting ready to send a -v2. If you set
> --in-reply-to=ask, it'll show you a list of emails you've recently sent,
> and their subject lines, and ask you to pick one to use the message ID
> from. It'll set the In-Reply-To header to your selection.

It sounds to me like you mean to call this during `git format-patch` - that is, `git format-patch -v2 --cover-letter --in-reply-to=ask master..branch -o branch/`. That should set the In-Reply-To: header on your cover letter.

There's also the possibility that you mean `git send-email --in-reply-to=ask branch/v2*` - in which case I imagine the In-Reply-To: is added as the message is sent, but not added to the cover letter text file.

> 
> I'd also like to add a custom header, X-Patch-Supersedes: <message ID>,
> with a similar behavior & purpose.

Is the hope to store the message ID you choose from --in-reply-to=ask into the X-Patch-Supersedes: header? I'm not sure I understand what you're trying to solve; if you use `git format-patch --in-reply-to` it sounds like the X-Patch-Supersedes: and In-Reply-To: would be redundant.

Is it possible you mean you want (sorry for pseudocode scribblings) [PATCH v2 1/1]->X-Patch-Supersedes = [PATCH 1/1]->Message-Id ? I think that wouldn't look good in a threaded mail client?

> 
> Thoughts?

Or maybe I totally misunderstood :)

What I think might be useful (and what I was hoping you were going to talk about when I saw the subject line) would be if the Message-Id is conveniently stored during `git send-email` on v1 and somehow saved in a useful place in order to apply to the In-Reply-To field on v2 automatically upon `git format-patch -v2`. I'll admit I didn't know about --in-reply-to=ask and that helps with the pain point I've experienced sending out v2 before.

 - Emily