Re: [Article display mess up] SOLVED! (-> FAQ ???)

[Jan Vroonhof <vroonhof@math.ethz.ch>]

 writes:

[From a discussion about a problem where the group name gets insert by
the picons all over the headers on the very firt message you read]

> Lars> Guessing wildly, I think this sounds like a glyph glitch.  Is the text
> Lars> really there, or does it just look like it's there?  
> 
> I'm guessing something similiar...  A lot of people (ok, 5 or 6) have
> reported similar problems too me but I've never been able to reproduce
> it or see it happen so I'm a bit confused really...  I guessed it was
> probably a bug with XEmacs not picons or gnus, but I can't be sure...

I solved it.. It is a RTFM type operator error. It is produced by
something like the following in .gnus

(setq gnus-picons-display-where 'article)
(add-hook 'gnus-article-display-hook 'gnus-article-display-picons t)
(add-hook 'gnus-summary-prepare-hook 'gnus-group-display-picons t)

You get this if you copy the example out of the Info file and then
change the first line to say 'article without reading the
documentations for the other functions. I did exactly that and I think
there are some others with the above lines in their .gnus's

It SHOULD read of course

(setq gnus-picons-display-where 'article)
(add-hook 'gnus-article-display-hook 'gnus-article-display-picons t)
(add-hook 'gnus-article-prepare-hook 'gnus-group-display-picons t)

which works fine.

The junk is generated when upon entering a group
gnus-summary-prepare-hook gets run. With the above setiings it trys to
insert an annotation in the article buffer. If this is the first
message you read, there is none. Therefore the following code in
gnus-group-display-picons

    (save-excursion
      (set-buffer (get-buffer-create
		   (gnus-get-buffer-name gnus-picons-display-where)))
      (gnus-add-current-to-buffer-list)


creates the article buffer and inserts an annoation with the group
name. This annotation has a "begin-glyph" property set to the group
icon/name. This wouldn't be a problem, BUT the gnus
article-fancification code does not expect this and creates
annotations/extents itself each one inheriting the begin-glyph
property. This gives a group "icon" for every extent which creates the
mess.

So I suggest that

1.  the example in the Info files is extended by comments explaining
    that this choice of hooks corresponds to only this choice for
    g-p-d-where
2. The picon hook functions refrain from creating one of the Gnus
   special buffers (i.e. *Article*) itself but instead give an error.
and/or
3. The picon functions are made more intelligent with a special
   gnus-picon-summary-hook-function and similar
   g-p-article-hook-function which will do the right thing
   automagically based on the value of g-p-d-where. 

Jan

P.S. This extent stuff is an horror to debug.