bug#18090: 24.4.50; `delete-selection-helper' logic changed for non-mouse region?

[Drew Adams]

> That change was made due to problems described in this thread:
> 
>   https://urldefense.proofpoint.com/v2/url?u=http-
> 3A__lists.gnu.org_archive_html_emacs-2Ddevel_2007-
> 2D06_msg01642.html&d=DwIBAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMU
> B65eapI_JnE&r=kI3P6ljGv6CTHIKju0jqInF6AOwMCYRDQUmqX22rJ98&m=1Sma
> MGY0ePhv2v_dZNfjfbgjYaW_usF7c6AeSBPND4A&s=tjJCnI84nM3eLwqFSz2ImzZ
> U1RBUgqh9dbJs3SvCK_w&e=
> 
> FWIW, I cannot reproduce the original problem reported by Juri in that
> thread, in Emacs 22.1, which according to my calculations was released
> before the change.  So I cannot dig deeper into the issue, but my
> first thought was that this code needs to be rethought/augmented due
> to changes in Emacs 24 regarding selections, since currently the
> default is not to copy to the kill-ring the region selected by
> dragging the mouse.
> 
> I also don't think I understand your report, Drew.  What exactly is
> the problem you are complaining about?  Surely, the problem is not the
> code, but its effect; however, all you say about the effect is that
> "yanking point is rotated only when the mouse was used".  I don't
> understand what "rotating yanking point" means, let alone why it is
> problematic.
> 
> I hope Juri, who made that change, will be able to investigate some
> more.

I have my own code for `delete-selection-mode' stuff, including my
own version of ` delete-selection-helper'. I added the two lines that
were added to the vanilla version for reference, but I commented
them out. I see no need for them - no problem without them. And
I think it doesn't make sense to treat the mouse differently here.

 (while (and tail  (string= (buffer-substring-no-properties (point) (mark))
           ;; Vanilla Emacs has this, which seems very wrong.
           ;; See Emacs bug #18090.
           ;;;   (fboundp 'mouse-region-match)
           ;;;   (mouse-region-match)
           )

I can't add more than that, I'm afraid. I don't see the bug that Juri
reports, even though the code I use does not have those two
commented lines.