Re: kill-new may replace the wrong item

[Juri Linkov]

> All I am trying to point out is there's something incorrect there.

The whole implementation of `kill-do-not-save-duplicates' is incorrect.
It should do nothing instead of setting `replace' to t and replacing the
same string with itself (that may override the value pushed from
`interprogram-paste' to `kill-ring').

I believe this patch will provide the consistent interaction between
`kill-do-not-save-duplicates' and `save-interprogram-paste-before-kill'.
Before pushing a string to kill-ring it compares the head of kill-ring with
the string from interprogram-paste and later with the input argument `string':

=== modified file 'lisp/simple.el'
--- lisp/simple.el      2010-05-19 19:17:29 +0000
+++ lisp/simple.el      2010-06-03 19:16:18 +0000
@@ -3009,24 +3009,25 @@ (defun kill-new (string &optional replac
     (if yank-handler
        (signal 'args-out-of-range
                (list string "yank-handler specified for empty string"))))
-  (when (and kill-do-not-save-duplicates
-             (equal string (car kill-ring)))
-    (setq replace t))
   (if (fboundp 'menu-bar-update-yank-menu)
       (menu-bar-update-yank-menu string (and replace (car kill-ring))))
   (when save-interprogram-paste-before-kill
     (let ((interprogram-paste (and interprogram-paste-function
                                    (funcall interprogram-paste-function))))
       (when interprogram-paste
-        (if (listp interprogram-paste)
-            (dolist (s (nreverse interprogram-paste))
-              (push s kill-ring))
-            (push interprogram-paste kill-ring)))))
-  (if (and replace kill-ring)
-      (setcar kill-ring string)
-    (push string kill-ring)
-    (if (> (length kill-ring) kill-ring-max)
-       (setcdr (nthcdr (1- kill-ring-max) kill-ring) nil)))
+        (dolist (s (if (listp interprogram-paste)
+                      (nreverse interprogram-paste)
+                    (list interprogram-paste)))
+         (unless (and kill-do-not-save-duplicates
+                      (equal s (car kill-ring)))
+           (push s kill-ring))))))
+  (unless (and kill-do-not-save-duplicates
+              (equal string (car kill-ring)))
+    (if (and replace kill-ring)
+       (setcar kill-ring string)
+      (push string kill-ring)
+      (if (> (length kill-ring) kill-ring-max)
+         (setcdr (nthcdr (1- kill-ring-max) kill-ring) nil))))
   (setq kill-ring-yank-pointer kill-ring)
   (if interprogram-cut-function
       (funcall interprogram-cut-function string (not replace))))

-- 
Juri Linkov
http://www.jurta.org/emacs/