bug#47130: 28.0.50; Gnus: mairix doesn't work anymore

[Eric Abrahamsen <eric@ericabrahamsen.net>]

On 03/17/21 02:02 AM, Michael Heerdegen wrote:
> Eric Abrahamsen <eric@ericabrahamsen.net> writes:
>
>> So maybe you're running into the exact same bug as before, via a
>> different path? :)
>
> Tried my luck on debugging, but it's really hard for me.
>
> What I can say is that `nnselect-retrieve-headers' does not retrieve any
> headers but gives up instead.  I'm not sure if there is a problem with
> paths or whatever.  While debugging, in one of 10 trials then the thing
> suddenly worked (!), I could see the expected matches but I did not find
> a pattern what was different at that moment.  And quitting the group
> then gave the error
>
> | gnus-list-of-unread-articles: Group
> nnml+archive:home.micha.Mail.archive..emacs couldn't be activated
>
> Hope somebody knowing the code can reproduce the issue.

I was finally able to get mairix to index a test server, and searching
worked just fine. One thing I realized afterwards is that I had set the
remove-prefix to the directory where the actual mails are kept
("/home/eric/Mail"), whereas it looks like you've set it to the
directory where mairix is supposed to put its search-result symlinks
("/home/micha/mairix").

This is the main difference between nnmairix and gnus-search with
mairix: nnmairix actually creates new groups and reads them directly,
gnus-search returns a list of results that refer to messages on the
original server. The "-r" option is passed to mairix, which tells it not
to create its own folders but return the original file names of matched
results -- that's why remove-prefix has to refer to the underlying
server.

Hope that makes sense. I suppose I should add a note to the
documentation?

Eric