bug#58479: 29.0.50; [feature/noverlay] Displaced overlays in notmuch search buffers after refreshing

[Matt Armstrong <matt@rfc20.org>]

Ihor Radchenko <yantar92@posteo.net> writes:

> Matt Armstrong <matt@rfc20.org> writes:
>
>>> See the recorded video link. Basically, I just executed M-x
>>> describe-text-properties after (3) in my second recipe.
>>
>> Ihor, I can't reproduce this second issue.  I can't see your video.
>> Firefox on Debian Testing can't decode it for some reason.
>
> You can download it and open locally.
> Also, do note that the second issue was present _before_ Stefan's patch.
> Then, Stefan expressed a concern that even though the patch fixed
> immediate problem, it might be creating other issues are he did not
> anticipate the patch to make any difference in the output of
> describe-text-properties (AFAIU).

Okay, I'm able to watch your video and think I see what you're talking
about there, but I am not able to reproduce a problem with the Stefan's
fix applied.  Maybe there is some miscommunication.  Everything I try
now seems to work the same on master and the most recent
feature/noverlay.  Could you start from the beginning and provide steps?
I am a little lost with "press this after third step of that after
watching video."  :-)

The "Hello, World" string was a little confusing.  Here is a simpler
version:

(defun my-b58479-3 ()
  (interactive)
  (with-current-buffer (get-buffer-create "*b58479*")
    (add-to-invisibility-spec (cons 'ellipsis t))
    (erase-buffer)
    (delete-all-overlays)
    (insert "123456789")
    (let ((overlay (make-overlay 2 9)))
      (overlay-put overlay 'invisible 'ellipsis))
    (display-buffer (current-buffer))))

Looks like `describe-text-properties' first tries `overlays-at' and,
finding nothing, will try (overlays-in (point) (1+ (point))) to get the
zero-width overlays.

-- 
matt (sent from an Emacs running the feature/noverlay branch)