* lisp/simple.el (undo-amalgamate-change-group): New function

* lisp/emulation/viper-cmd.el (viper-adjust-undo): Use it.
(viper-set-complex-command-for-undo): Save current state with
prepare-change-group.
* lisp/emulation/viper-init.el (viper-undo-needs-adjustment)
(viper-buffer-undo-list-mark): Remove.

2 files changed, 11 insertions, 40 deletions

diff --git a/lisp/emulation/viper-cmd.el b/lisp/emulation/viper-cmd.el
index 3d9d1cc59f2..3ce1b4d6a75 100644
--- a/lisp/emulation/viper-cmd.el
+++ b/lisp/emulation/viper-cmd.el
@@ -1709,40 +1709,20 @@ invokes the command before that, etc."
 ;; The following two functions are used to set up undo properly.
 ;; In VI, unlike Emacs, if you open a line, say, and add a bunch of lines,
 ;; they are undone all at once.
-(defun viper-adjust-undo ()
-  (if viper-undo-needs-adjustment
-      (let ((inhibit-quit t)
-	    tmp tmp2)
-	(setq viper-undo-needs-adjustment nil)
-	(when (listp buffer-undo-list)
-          (let ((had-boundary (null (car buffer-undo-list))))
-            (if (setq tmp (memq viper-buffer-undo-list-mark buffer-undo-list))
-		(progn
-		  (setq tmp2 (cdr tmp)) ; the part after mark
-
-		  ;; cut tail from buffer-undo-list temporarily by direct
-		  ;; manipulation with pointers in buffer-undo-list
-		  (setcdr tmp nil)
-
-		  (setq buffer-undo-list (delq nil buffer-undo-list))
-		  (setq buffer-undo-list
-			(delq viper-buffer-undo-list-mark buffer-undo-list))
-		  ;; restore tail of buffer-undo-list
-		  (setq buffer-undo-list (nconc buffer-undo-list tmp2)))
-	      (setq buffer-undo-list (delq nil buffer-undo-list)))
-            ;; The top-level loop only adds boundaries if there has been
-            ;; modifications in the buffer, so make sure we don't accidentally
-            ;; drop the "final" boundary (bug#22295).
-	    (if had-boundary (undo-boundary)))))))
+(viper-deflocalvar viper--undo-change-group-handle nil)
+(put 'viper--undo-change-group-handle 'permanent-local t)
 
+(defun viper-adjust-undo ()
+  (when viper--undo-change-group-handle
+    (undo-amalgamate-change-group
+     (prog1 viper--undo-change-group-handle
+       (setq viper--undo-change-group-handle nil)))))
 
 (defun viper-set-complex-command-for-undo ()
-  (if (listp buffer-undo-list)
-      (if (not viper-undo-needs-adjustment)
-	  (let ((inhibit-quit t))
-	    (setq buffer-undo-list
-		  (cons viper-buffer-undo-list-mark buffer-undo-list))
-	    (setq viper-undo-needs-adjustment t)))))
+  (and (listp buffer-undo-list)
+       (not viper--undo-change-group-handle)
+       (setq viper--undo-change-group-handle
+             (prepare-change-group))))
 
 
 ;;; Viper's destructive Command ring utilities
diff --git a/lisp/emulation/viper-init.el b/lisp/emulation/viper-init.el
index cd71925590a..ee093906771 100644
--- a/lisp/emulation/viper-init.el
+++ b/lisp/emulation/viper-init.el
@@ -369,15 +369,6 @@ Use `\\[viper-set-expert-level]' to change this.")
 
 ;; VI-style Undo
 
-;; Used to 'undo' complex commands, such as replace and insert commands.
-(viper-deflocalvar viper-undo-needs-adjustment nil)
-(put 'viper-undo-needs-adjustment 'permanent-local t)
-
-;; A mark that Viper puts on buffer-undo-list.  Marks the beginning of a
-;; complex command that must be undone atomically.  If inserted, it is
-;; erased by viper-change-state-to-vi and viper-repeat.
-(defconst viper-buffer-undo-list-mark 'viper)
-
 (defcustom viper-keep-point-on-undo nil
   "Non-nil means not to move point while undoing commands.
 This style is different from Emacs and Vi.  Try it to see if