bug#49115: Mumi inserts spurious underscore in bug title

[Arun Isaac <arunisaac@systemreboot.net>]

Hi Ricardo,

Thanks for the bug report!

It's very strange, but I'm not able to reproduce this. I tried the
following. bug_49114.mbox is downloaded from
https://debbugs.gnu.org/cgi/bugreport.cgi?mbox=yes;bug=49114

--8<---------------cut here---------------start------------->8---
(use-modules (email email))

(pk
 (parse-email-headers "Subject: bug#49114: =?UTF-8?Q?=E2=80=98guix_?= =?UTF-8?Q?lint=E2=80=99?= should catch certificate validation exceptions
"))

(for-each (lambda (bv)
            (pk (assoc-ref (email-headers (parse-email bv))
                           'subject)))
          (call-with-input-file "bug_49114.mbox"
            mbox->emails))
--8<---------------cut here---------------end--------------->8---

Even at https://issues.guix.gnu.org/49114 , only the "bug title" has the
spurious underscore. The subject of the first message does not. Is the
bug title something stored in the xapian index? Could it be that this
was an older bug that has corrupted the xapian index?

If I understand correctly, mumi does not rebuild its xapian index. I
think it should do so from time to time. It would help prevent old bugs
from getting persisted in storage.

Cheers, and wish you a Happy New Year! :-)
Arun