bug#27584: 26.0.50; alist-get: Add optional arg TESTFN

[Eli Zaretskii]

> From: Nicolas Petton <nicolas@petton.fr>
> Date: Fri, 07 Jul 2017 21:47:03 +0200
> Cc: 27584@debbugs.gnu.org, Tino Calancha <tino.calancha@gmail.com>
> 
> +      if (NILP (testfn))
> +     {
> +       if (CONSP (car)
> +           && (EQ (XCAR (car), key) || !NILP (Fequal (XCAR (car), key))))
> +         return car;
> +     }
> +      else if (CONSP (car) && (!NILP (call2 (testfn, (XCAR (car)), key))))
> +     {
> +       return car;
> +     }

No need for braces when there's only one line to enclose.
Also, no need for parentheses around "!NILP (...)".

Bonus points for simplifying the code by determining TESTFN up front,
then having only one of the above two clauses.

Thanks.