(kill-whole-line): Make it interact correctly with the kill ring.

diff --git a/lisp/simple.el b/lisp/simple.el
index 3dcbb73f11408c13f18e4b2bf8f7b2366eec4595..6a382d8c5503a0a3ca4b9dda9a1a24a2290e0540 100644 (file)
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -2210,23 +2210,41 @@ even beep.)"
 
 (defun kill-whole-line (&optional arg)
   "Kill current line.
-With prefix arg, kill that many lines from point.
-If arg is negative, kill backwards.
+With prefix arg, kill that many lines starting from the current line.
+If arg is negative, kill backward.  Also kill the preceding newline.
+\(This is meant to make C-x z work well with negative arguments.\)
 If arg is zero, kill current line but exclude the trailing newline."
   (interactive "P")
   (setq arg (prefix-numeric-value arg))
+  (if (and (> arg 0) (eobp) (save-excursion (forward-visible-line 0) (eobp)))
+      (signal 'end-of-buffer nil))
+  (if (and (< arg 0) (bobp) (save-excursion (end-of-visible-line) (bobp)))
+      (signal 'beginning-of-buffer nil))
+  (unless (eq last-command 'kill-region)
+    (kill-new "")
+    (setq last-command 'kill-region))
   (cond ((zerop arg)
-        (kill-region (point) (progn (forward-visible-line 0) (point)))
+        ;; We need to kill in two steps, because the previous command
+        ;; could have been a kill command, in which case the text
+        ;; before point needs to be prepended to the current kill
+        ;; ring entry and the text after point appended.  Also, we
+        ;; need to use save-excursion to avoid copying the same text
+        ;; twice to the kill ring in read-only buffers.
+        (save-excursion
+          (kill-region (point) (progn (forward-visible-line 0) (point))))
         (kill-region (point) (progn (end-of-visible-line) (point))))
        ((< arg 0)
-        (kill-line 1)
-        (kill-line (1+ arg))
-        (unless (bobp) (forward-visible-line -1)))
+        (save-excursion
+          (kill-region (point) (progn (end-of-visible-line) (point))))
+        (kill-region (point)
+                     (progn (forward-visible-line (1+ arg))
+                            (unless (bobp) (backward-char))
+                            (point))))
        (t
-        (kill-line 0)
-        (if (eobp)
-            (signal 'end-of-buffer nil)
-          (kill-line arg)))))
+        (save-excursion
+          (kill-region (point) (progn (forward-visible-line 0) (point))))
+        (kill-region (point)
+                     (progn (forward-visible-line arg) (point))))))
 
 (defun forward-visible-line (arg)
   "Move forward by ARG lines, ignoring currently invisible newlines only.