bug#48936: 27.2; pulse-reset-face and extend attribute of pulse-highligh-face

[Gustavo Barros]

Hi Lars,

On Sun, 13 Jun 2021 at 09:49, Lars Ingebrigtsen <larsi@gnus.org> wrote:

> Gustavo Barros <gusbrs.2016@gmail.com> writes:
>
> > Considering the role `pulse-highlight-face' plays in the way `pulse' 
> > works, it would be expected that this resetting should also be done 
> > for 
> > the `:extend' attribute when the function is called without an 
> > argument, 
>
> I think that sounds correct, so I've now made this change in Emacs 28.

Thank you for looking into this.

But my suggestion was more the one to use the `:extend' attribute of 
`pulse-highlight-start-face' to reset `pulse-highlight-face'. Like:

#+begin_src emacs-lisp
(set-face-extend 'pulse-highlight-face
                (if face 
                    (face-extend-p face nil t)
                  (face-extend-p 'pulse-highlight-start-face)))
#+end_src

Because `pulse-highlight-start-face' is the default face `pulse' uses 
when the `pulse-momentary-highlight-...' functions are called without 
argument.  This makes `pulse-highlight-start-face' the only possible 
handle for setting the `:extend' attribute for calls of `pulse' 
functions without argument. If you just set it to nil when a call with 
no argument is made, we can still only get a pulse to work with 
`:extend' by explicitly passing the argument.

Btw, this is the same treatment `:background' receives. Why should we 
treat both face attributes differently?

Best regards,
Gustavo.