(vc-rename-file): Don't overwrite an existing file.

Fix test for unsaved files.
Calculate name of new master file properly.

1 files changed, 27 insertions, 8 deletions

diff --git a/lisp/vc.el b/lisp/vc.el
index 5adf1ca8147..145be72c7c5 100644
--- a/lisp/vc.el
+++ b/lisp/vc.el
@@ -1137,19 +1137,38 @@ A prefix argument means do not revert the buffer afterwards."
   "Rename file OLD to NEW, and rename its master file likewise."
   (interactive "fVC rename file: \nFRename to: ")
   (let ((oldbuf (get-file-buffer old)))
-    (if (buffer-modified-p oldbuf)
+    (if (and oldbuf (buffer-modified-p oldbuf))
         (error "Please save files before moving them"))
     (if (get-file-buffer new)
         (error "Already editing new file name"))
+    (if (file-exists-p new)
+        (error "New file already exists"))
     (let ((oldmaster (vc-name old)))
       (if oldmaster
-        (if (vc-locking-user old)
-            (error "Please check in files before moving them"))
-        (if (or (file-symlink-p oldmaster)
-                ;; This had FILE, I changed it to OLD. -- rms.
-                (file-symlink-p (vc-backend-subdirectory-name old)))
-            (error "This is not a safe thing to do in the presence of symbolic links"))
-        (rename-file oldmaster (vc-name new)))
+          (progn
+            (if (vc-locking-user old)
+                (error "Please check in files before moving them"))
+            (if (or (file-symlink-p oldmaster)
+                    ;; This had FILE, I changed it to OLD. -- rms.
+                    (file-symlink-p (vc-backend-subdirectory-name old)))
+                (error "This is not a safe thing to do in the presence of symbolic links"))
+            (rename-file
+             oldmaster
+             (let ((backend (vc-backend-deduce old))
+                   (newdir (or (file-name-directory new) ""))
+                   (newbase (file-name-nondirectory new)))
+               (catch 'found
+                 (mapcar
+                  (function
+                   (lambda (s)
+                     (if (eq backend (cdr s))
+                         (let* ((newmaster (format (car s) newdir newbase))
+                                (newmasterdir (file-name-directory newmaster)))
+                           (if (or (not newmasterdir)
+                                   (file-directory-p newmasterdir))
+                               (throw 'found newmaster))))))
+                  vc-master-templates)
+                 (error "New file lacks a version control directory"))))))
       (if (or (not oldmaster) (file-exists-p old))
           (rename-file old new)))
 ; ?? Renaming a file might change its contents due to keyword expansion.