Re: gnus and imap

[Dan Christensen <jdc@uwo.ca>]

In 2008, regarding Vitaly Mayatskikh's patches, David Engster writes:

> I've finally come to test your patches. Sorry for the delay.
>
> I'm still sometimes encountering wrong article counts upon entering a
> group. This happens when I delete articles in a group and enter it
> without a rescan. The group will then show an unread count which is
> usually equal to the number of deleted articles. This gets reset to zero
> when you exit the group, so you can only see that with a three-pane
> view, where the group buffer is always visible.
>
> However, this is only indirectly a consequence of your patches. The
> problem seems to be that when you delete some articles in a group, the
> active information does not get updated in the hash table, so that
> (gnus-range-difference active range) will return a range containing the
> deleted articles.
>
> This is all fixable, of course. However, before continuing with this
> approach, I'd still like to suggest using a new backend function instead
> of storing the number of available articles numbers in the
> active-hashtb. The latter implies that we would have to check the whole
> Gnus trunk for regressions regarding usage of the active-hashtb, which
> will be a lot of work. I think that using something like
> nnimap-request-group-articles and leaving the active-hashtb as it is
> would be easier to do in the long term. If you (or others) don't object,
> I could try to change your patches using that new backend function.
>
> Best,
> David

I'm wondering if Vitaly or David have made any progress on the imap
unread count.  I'm using dovecot, and I regularly get wrong unread
counts in my nnimap groups, even with
gnus-fixup-nnimap-unread-after-getting-new-news in
gnus-after-getting-new-news-hook.

I think David's idea of adding an optional backend function which
returns more detailed information is the way to go.  The core of Gnus
can check for this function and use it if it exists, falling back to the
old way if not.  This allows for a gradual transition without needing
massive changes all at once.

Dan