(basic-save-buffer): Do not set visited filename when

the corresponding directory does not exist or the specified
filename is that of an existing directory.

diff --git a/lisp/files.el b/lisp/files.el
index 50180dc6ebf47f6cff743d988c2b60da69ec15a5..d0a89ec65b5f7897fcb62a0685a3cce67f09e45f 100644 (file)
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -3595,10 +3595,21 @@ Before and after saving the buffer, this function runs
              (let ((filename
                     (expand-file-name
                      (read-file-name "File to save in: ") nil)))
-               (and (file-exists-p filename)
-                    (or (y-or-n-p (format "File `%s' exists; overwrite? "
-                                          filename))
-                        (error "Canceled")))
+               (if (file-exists-p filename)
+                   (if (file-directory-p filename)
+                       ;; Signal an error if the user specified the name of an
+                       ;; existing directory.
+                       (error "%s is a directory" filename)
+                     (unless (y-or-n-p (format "File `%s' exists; overwrite? "
+                                               filename))
+                       (error "Canceled")))
+                 ;; Signal an error if the specified name refers to a
+                 ;; non-existing directory.
+                 (let ((dir (file-name-directory filename)))
+                   (unless (file-directory-p dir)
+                     (if (file-exists-p dir)
+                         (error "%s is not a directory" dir)
+                       (error "%s: no such directory" dir)))))
                (set-visited-file-name filename)))
          (or (verify-visited-file-modtime (current-buffer))
              (not (file-exists-p buffer-file-name))