bug#54733: Match again in perform-replace

[Dmitry Gutov]

Hi Juri,

Thanks for working on this.

On 03.05.2022 10:10, Juri Linkov wrote:
> +                               (replace-search search-string limit
> +                                               regexp-flag delimited-flag
> +                                               case-fold-search backward))

I don't know this code too well, but perhaps SEARCH_STRING here should 
be anchored with something like "\\=" at the beginning?

Otherwise the search can succeed here even if the next match is not 
here. Not sure how important that is, though.

> -         ;; Counteract the "do the next match now" hack in
> -         ;; `perform-replace'.  And still, it'll report that those
> -         ;; matches were "filtered out" at the end.
> -         (isearch-filter-predicate
> -          (lambda (beg end)
> -            (and current-beg
> -                 (>= beg current-beg)
> -                 (<= end current-end))))

Please note that we'll likely have to keep this code here for a number 
of Emacs releases. So the patch should be tested with both versions: 
with this code present and with it removed, to ensure present and future 
compatibility.