bug#43033: 27.1; Two zero-width overlays with before- and after-string property

[Ikumi Keita]

>>>>> Eli Zaretskii <eliz@gnu.org> writes:
>> 3. Expected result: *scrach* buffer displays "beforeAFTER" in it
>> Actual result: *scrach* buffer displays "AFTERbefore" in it

> This is the expected (albeit somewhat counter-intuitive) behavior:
> Emacs always sorts after-strings so that they come in front of
> before-strings, except if they are from the same overlay.  This
> behavior remained unchanged since Emacs 21.1.

>> [How this behavior affects my usage of overlay]
>> When the minibuffer has a zero-width overlay at the EOB with
>> before-string property, `set-minibuffer-message' displays that string
>> after, not before, the echo area message shown by that function.

> This is by design: we want the minibuffer message to be as visible as
> possible, so other overlays are pushed to the right (where they could
> be hidden if the screen space is insufficient).

OK, thanks. Then I'll customize `set-message-function' for my personal
usage.

Regards,
Ikumi Keita