🚀 go-pugleaf

GNU Emacs 18.53.11 on NeXT 1.0.1

Currently, nocasify is set as follows in perform-replace:
   (not (and case-fold-search case-replace
	     (string-equal from-string
			   (downcase from-string))))

However, there is no point in casifying if (upcase to-string) is the
same as to-string!  This is actually a pretty common case (to-string
is empty, or consists only of punctuation, etc.).  So I would suggest:

   (or (not (and case-fold-search case-replace
		 (string-equal from-string
			       (downcase from-string))))
       (string-equal to-string (upcase to-string)))

or (equivalent but perhaps less clear):

   (not (and case-fold-search case-replace
	     (string-equal from-string
			   (downcase from-string))
	     (not (string-equal to-string (upcase to-string)))))