Repair pdbtrack so it follows transition from one remote file to another.

* python.el (python-pdbtrack-set-tracked-buffer).

1 files changed, 10 insertions, 4 deletions

diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index 9528ffeebbc..243125e310c 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -3635,12 +3635,18 @@ Never set this variable directly, use
   "Set the buffer for FILE-NAME as the tracked buffer.
 Internally it uses the `python-pdbtrack-tracked-buffer' variable.
 Returns the tracked buffer."
-  (let ((file-buffer (get-file-buffer
-                      (concat (file-remote-p default-directory)
-                              file-name))))
+  (let* ((file-name-prospect (concat (file-remote-p default-directory)
+                              file-name))
+         (file-buffer (get-file-buffer file-name-prospect)))
     (if file-buffer
         (setq python-pdbtrack-tracked-buffer file-buffer)
-      (setq file-buffer (find-file-noselect file-name))
+      (cond
+       ((file-exists-p file-name-prospect)
+        (setq file-buffer (find-file-noselect file-name-prospect)))
+       ((and (not (equal file-name file-name-prospect))
+             (file-exists-p file-name))
+        ;; Fallback to a locally available copy of the file.
+        (setq file-buffer (find-file-noselect file-name-prospect))))
       (when (not (member file-buffer python-pdbtrack-buffers-to-kill))
         (add-to-list 'python-pdbtrack-buffers-to-kill file-buffer)))
     file-buffer))