(undo): Remove positions from buffer-undo-list up to

the next undo boundary only.

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index c769848d7738c23e90ddffb0156bd467fe13a3d6..3a82065ceb57ed2b41e09e1c2189e2313db3b176 100644 (file)
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2001-09-06  Gerd Moellmann  <gerd@gnu.org>
+
+       * simple.el (undo): Remove positions from buffer-undo-list up to
+       the next undo boundary only.
+
 2001-09-06  Eli Zaretskii  <eliz@is.elta.co.il>
 
        * makefile.nt (install): Don't copy sc.el.  Reported by Richard

diff --git a/lisp/simple.el b/lisp/simple.el
index 8d2a5707898a60780ac6aa310e4dbc21c4df66a6..e276b1dea32a8fac90e2a72c47405efe6120ac1d 100644 (file)
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -961,13 +961,24 @@ as an argument limits undo to changes within the current region."
     ;; Don't specify a position in the undo record for the undo command.
     ;; Instead, undoing this should move point to where the change is.
     (let ((tail buffer-undo-list)
-         done)
-      (while (and tail (not done) (not (null (car tail))))
-       (if (integerp (car tail))
-           (progn
-             (setq done t)
-             (setq buffer-undo-list (delq (car tail) buffer-undo-list))))
-       (setq tail (cdr tail))))
+         (prev nil))
+      (while (car tail)
+       (when (integerp (car tail))
+         (let ((pos (car tail)))
+           (if (null prev)
+               (setq buffer-undo-list (cdr tail))
+             (setcdr prev (cdr tail)))
+           (setq tail (cdr tail))
+           (while (car tail)
+             (if (eq pos (car tail))
+                 (if prev
+                     (setcdr prev (cdr tail))
+                   (setq buffer-undo-list (cdr tail)))
+               (setq prev tail))
+             (setq tail (cdr tail)))
+           (setq tail nil)))
+       (setq prev tail tail (cdr tail))))
+
     (and modified (not (buffer-modified-p))
         (delete-auto-save-file-if-necessary recent-save)))
   ;; If we do get all the way thru, make this-command indicate that.