What does gnus-group-get-new-news do with arg=nil?

[David <de_bb@arcor.de>]

I tried to figure out what gnus-group-get-new-news actually does without
further arguments and with permanent levels unset, and I simply don't
get it. Please also note that the doc-string carefully avoids this
question. My impression was that gnus-activate-level would be used, but
it doesn't seem to be that easy.

The question boils down to what gnus-get-unread-articles does without
arguments, i.e. level=nil. What I'd like in this case is that every
group with a level greater than gnus-activate-level should be completely
ignored, but this doesn't happen. If level is nil, 'active' is never set
to 'ignore in the following code:

(if (and level
       ;; If `active' is nil that means the group has
       ;; never been read, the group should be marked
       ;; as having never been checked (see below).
       active
       (> (gnus-info-level info) level))
   ;; Don't check groups of which levels are higher
   ;; than the one that a user specified.
   (setq active 'ignore))))

Therefore, later in the code, gnus-get-unread-articles-in-group is
called, even for foreign groups with a level greater than gnus-activate-group:

(cond
   ((eq active 'ignore)
    ;; Don't do anything.
    )
    (active
       (inline (gnus-get-unread-articles-in-group info active t)))

Is this really the wanted behavior? It seems unnecessary to me - if I
just hit 'g' without a prefix, I think everything greater than
gnus-activate-level shouldn't be touched at all.

-David