Re: Bug in incremental undrawing of mouseover highlighting

[Stephen Berman <Stephen.Berman@gmx.net>]

On Sat, 20 Jan 2007 22:40:20 +0100 Stephen Berman
<Stephen.Berman@gmx.net> wrote: 

> Moreover, with the patch I haven't observed the mild form I
> mentioned (I don't have a precise recipe for reproducing that, but
> just experimented with patched and unpatched Emacsen from otherwise
> identical source code).

After seeing the problem Nick Roberts reported in the thread
"Flickering mouse-face" also in my patched Emacs, I did further
experimenting and did observe the milder form of incremental undrawing
with the patch.  I also have a somewhat unstable recipe for
reproducing it.  Currently, I see the problem with the following shows
(using the patch to xdisp.c applied in revision 1.1137):

1. emacs -Q

2. M-: (setq gnus-select-method '(nntp "news.gmane.org")) RET

3. M-x gnus RET

4. S s gmane.emacs.devel

5. Press RET on this group and at the prompt "How many articless from
gmane.emacs.devel (default 64519):" type 1000 RET

NB: The rest of this recipe depends on the top line in the Gnus
Summary buffer being this:
 . [ 273: Lennart Borgman        ] File name completion in *Shell* on w32

6. Put the mouse pointer between `[' and `]' on this line, so that
mouse-face highlighting is displayed.

7. Type `C-s 1 5 l :' and the C-g.  Now you will see mouse-face
highlighting in the first also in the space between `]' and `F', and
when you mouse the mouse pointer, that space still shows mouse-face.

Given this problem and the new problem reported by Nick Roberts, it
seems this patch is insufficient.

Steve Berman