Sending mail succeeded but signaled failure

[Justus Winter <justus@sequoia-pgp.org>]

Hello,

I just embarrassed myself a little by sending the same mail over and
over again.  The reason for that is that notmuch-emacs signaled failure,
i.e. it displayed an error message in the status buffer and didn't close
the compose buffer, yet it did in fact send the mail.

I suspect that my configuration has to do with that and someone is
trying to be helpful.  So I use msmtp with the authentication password
encrypted using OpenPGP.  Then, I use 'gpg --no-tty -q -d ...' as
msmtp's passwordeval function.  Now, my OpenPGP key has expired, but
that doesn't stop GnuPG from decrypting the secret, and in fact it
returns the status code 0.  It also prints

  gpg: Note: secret key 08CC70F8D8CC765A expired at Mon 25 Jul 2022 05:31:26 PM CEST

to stderr, which is picked up by notmuch-emacs, it says

  sending...failed to gpg: Note: secret key 08CC70F8D8CC765A expired at Mon 25 Jul 2022 05:31:26 PM CEST

in the status buffer while the compose buffer stays open.

I suspect that this is not notmuch's fault, but I don't know where else
to turn to with this bug report.

Best,
Justus