bug#71856: 30.0.50; string-pad length vs width

[Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

>> Is it just we or we should `s/length/width/` on the doc&code of
>> `string-pad`?  AFAIK counting codepoints rarely makes sense (unless
>> those code points have width==1, of course).
>> Same for `string-fill`.
> I think that makes sense.

Thanks.

>> I'd usually assume it was an oversight, but the doc keeps repeating
>> "length" enough times (and it's right next to `string-limit` which
>> insists it's about length).
>
> Could this have been an oversight there also?

No, this one is definitely done on purpose: for actual width, we already
have another function and `string-limit` explicitly refers to it.
[ Maybe the `coding-system` arg of `string-limit` should be mandatory,
  since it seems to be the most important use-case, tho.  ]


        Stefan