bug#15361: git send-email creates one report per patch

[Glenn Morris]

Package: debbugs.gnu.org

If you send a collection of patches to bug-foo via git send-email,
it creates one report per patch. Here's why:

How it normally works:

You send a new report to the bug-foo mailing list.
You get an ack saying "thanks, reply to address@hidden with more info".
When the mail arrives at the bug-foo mailing list after processing,
it has "Bug#123" in the subject, and seems to be addressed "To: address@hidden".

If someone sends a reply, it either has "Re: Bug#123" in the subject, or
it goes to address@hidden In either case, it is trivial for debbugs to
work out that the message is a reply to an existing bug rather than a
new report.

The lovely emails sent by git have no consistent subject and are all
addressed to bug-foo. Thus, there is no way to tell they are all
related except by tracking the message-id of the original report and
looking for a references: header in later emails.

I did actually implement that, but it replies on the message-id getting
into the bug database index, which is only updated every 5(?) minutes or
so. When a bunch of emails arrive all at the same time, as from git, it
cannot work.

To fix this, need to force message-id into the index immediately after a
new report arrives. I don't know how much work that is, or when I'll
have time to look at it.

Workaround: first create a report ("here's the problem for which I will
send a patch"), then send patches to that bug number rather than bug-foo.