(x-select-text): Remember selected text.

(x-get-selection-value): Return nil if the clipboard data is
is the same as the remembered selected text.

1 files changed, 11 insertions, 2 deletions

diff --git a/lisp/term/w32-win.el b/lisp/term/w32-win.el
index c6d94f09252..b2c6b923a27 100644
--- a/lisp/term/w32-win.el
+++ b/lisp/term/w32-win.el
@@ -488,7 +488,8 @@ This is in addition to the primary selection.")
 
 (defun x-select-text (text &optional push)
   (if x-select-enable-clipboard 
-      (win32-set-clipboard-data text)))
+      (win32-set-clipboard-data text))
+  (setq x-last-selected-text text))
     
 ;;; Return the value of the current selection.
 ;;; Consult the selection, then the cut buffer.  Treat empty strings
@@ -501,7 +502,15 @@ This is in addition to the primary selection.")
             (setq text (win32-get-clipboard-data))
           (error (message "win32-get-clipboard-data:%s" c)))
         (if (string= text "") (setq text nil))
-        text)))
+        (cond
+         ((not text) nil)
+         ((eq text x-last-selected-text) nil)
+         ((string= text x-last-selected-text)
+          ;; Record the newer string, so subsequent calls can use the 'eq' test.
+          (setq x-last-selected-text text)
+          nil)
+         (t
+          (setq x-last-selected-text text))))))
 
 ;;; Do the actual Windows setup here; the above code just defines
 ;;; functions and variables that we use now.