Re: [RFC PATCH] send-email: allow a custom hook to prevent sending email

Stefan Beller [off-list ref] writes:

$ git send-email 00* --cc=list --cc=bmwill --cc=duy --to=jch
0000-cover-letter.patch
...
(mbox) Adding cc: Stefan Beller [off-list ref] from line 'From:
Stefan Beller [off-list ref]'

From: Stefan Beller <redacted>
To: gitster@pobox.com
Cc: git@vger.kernel.org,
bmwill@google.com,
pclouds@gmail.com,
Stefan Beller [off-list ref]
Subject: [PATCHv7 0/6] submodule absorbgitdirs
Date: Mon, 12 Dec 2016 11:04:29 -0800
Message-Id: [ref]
X-Mailer: git-send-email 2.11.0.rc2.49.ge1f3b0c.dirty

Send this email? ([y]es|[n]o|[q]uit|[a]ll):

---
This is usually where I just say "a" and carry on with life.
The hook would ideally reformat the last lines to be
---
    X-Mailer: git-send-email 2.11.0.rc2.49.ge1f3b0c.dirty
    send-email hook thinks it is a bad idea to send out this series:
    <output of hook, e.g.
    referencing a typo in patch 5.
    or a mismatch of patch version numbers>

    Send this email? ([y]es|[n]o|[q]uit|[a]ll):
---

Yup, sounds sensible (the "... thinks it is a bad idea ..." line may
probably not be needed; the hook can say why it is unhappy itself).

Thanks.