Restore initial undo boundary with viper

* lisp/emulation/viper-cmd.el (viper-adjust-undo): Add back last undo
  boundary if it has been removed.

Addresses Bug#22295.

1 files changed, 8 insertions, 4 deletions

diff --git a/lisp/emulation/viper-cmd.el b/lisp/emulation/viper-cmd.el
index 93cf3b0fb10..4bd819ab828 100644
--- a/lisp/emulation/viper-cmd.el
+++ b/lisp/emulation/viper-cmd.el
@@ -1715,8 +1715,9 @@ invokes the command before that, etc."
       (let ((inhibit-quit t)
             tmp tmp2)
         (setq viper-undo-needs-adjustment nil)
-        (if (listp buffer-undo-list)
-            (if (setq tmp (memq viper-buffer-undo-list-mark buffer-undo-list))
+        (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
 
@@ -1729,8 +1730,11 @@ invokes the command before that, etc."
                         (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)))))
-    ))
+              (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)))))))
 
 
 (defun viper-set-complex-command-for-undo ()