BUG: "notmuch insert" fails with "Delivery of non-mail file"

[Alvaro Herrera <alvherre@alvh.no-ip.org>]

Hello

I've been using notmuch successfully for a couple of years now (mostly
via neomutt).  Thanks for developing it.

Not long ago I switched my mail setup to use notmuch insert via
mailfilter instead of good old procmail.  However, since then a number
of emails are reported by notmuch as "non-mail", and appear to not be
indexed.  (I use --keep, so they're still in my maildir).

In my read of the code ultimately comes from
g_mime_parser_construct_message rejecting the message.
I reported this to GMime, and they said that the problem is that notmuch
insert is using the mbox mode:
https://github.com/jstedfast/gmime/issues/58
(Sample email is attached there).

As far as I can tell, this is all coming from
_notmuch_message_file_parse() which sets the is_mbox flag when it sees
the "^From " line at the start of the file ... which kinda makes sense
in general terms, but for notmuch-insert I think that's the wrong thing
to do.  Maybe a solution is to pass a flag down from notmuch-insert.c's
add_file all the way down to _notmuch_message_file_parse telling it not
to treat the file as an mbox.

I *think* that not all of the messages that fail parsing contain an
email attachment, so maybe I'll come back with further issues later on.
This is the first one I debugged.

Thanks

-- 
Álvaro Herrera