emacs-29 ed3bab3cc72: Revert 'forward-sentence-default-function' to return point (bug#62027)

[Eli Zaretskii]

branch: emacs-29
commit ed3bab3cc728f19f8691024a3b77e178cf1945e6
Author: Manuel Giraud <manuel@ledu-giraud.fr>
Commit: Eli Zaretskii <eliz@gnu.org>

    Revert 'forward-sentence-default-function' to return point (bug#62027)
    
    * lisp/textmodes/paragraphs.el
    (forward-sentence-default-function): Revert to return the
    position of point.
    (count-sentences): Adapt to this change.
---
 lisp/textmodes/paragraphs.el | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/lisp/textmodes/paragraphs.el b/lisp/textmodes/paragraphs.el
index 73abb155aaa..a9e28a3275b 100644
--- a/lisp/textmodes/paragraphs.el
+++ b/lisp/textmodes/paragraphs.el
@@ -477,8 +477,7 @@ sentences.  Also, every paragraph boundary terminates 
sentences as well."
            (skip-chars-backward " \t\n")
          (goto-char par-end)))
       (setq arg (1- arg)))
-    (let ((npoint (constrain-to-field nil opoint t)))
-      (not (= npoint opoint)))))
+    (constrain-to-field nil opoint t)))
 
 (defun count-sentences (start end)
   "Count sentences in current buffer from START to END."
@@ -488,8 +487,13 @@ sentences.  Also, every paragraph boundary terminates 
sentences as well."
       (save-restriction
         (narrow-to-region start end)
         (goto-char (point-min))
-       (while (ignore-errors (forward-sentence))
-         (setq sentences (1+ sentences)))
+        (let* ((prev (point))
+               (next (forward-sentence)))
+          (while (and (not (null next))
+                      (not (= prev next)))
+            (setq prev next
+                  next (ignore-errors (forward-sentence))
+                  sentences (1+ sentences))))
         ;; Remove last possibly empty sentence
         (when (/= (skip-chars-backward " \t\n") 0)
           (setq sentences (1- sentences)))