(mail): Improve confirmation questions for file-visiting mail buffers.

diff --git a/lisp/mail/sendmail.el b/lisp/mail/sendmail.el
index 6fe9349f6223916bed21790b602041aa0aaa8bac..8ad9778f84528f80bb3acb1ff7732723fc7ccdb2 100644 (file)
--- a/lisp/mail/sendmail.el
+++ b/lisp/mail/sendmail.el
@@ -1237,10 +1237,19 @@ The seventh argument ACTIONS is a list of actions to take
 ;  (set-visited-file-name nil)
   (let (initialized)
     (and (not noerase)
-        (or (not (buffer-modified-p))
-            (if buffer-file-name
-                (y-or-n-p "Buffer is modified; erase it and reinitialize? ")
-              (y-or-n-p "Unsent message being composed; erase it? ")))
+        (if buffer-file-name
+            (if (buffer-modified-p)
+                (when (y-or-n-p "Buffer has unsaved changes; reinitialize it and discard them? ")
+                  (if (y-or-n-p "Disconnect buffer from visited file? ")
+                      (set-visited-file-name nil))
+                  t)
+              (when (y-or-n-p "Reinitialize buffer, and disconnect it from the visited file? ")
+                (set-visited-file-name nil)
+                t))
+          ;; A non-file-visiting buffer.
+          (if (buffer-modified-p)
+              (y-or-n-p "Unsent message being composed; erase it? ")
+            t))
         (let ((inhibit-read-only t))
           (erase-buffer)
           (mail-setup to subject in-reply-to cc replybuffer actions)