Fix type check in tramp-get-buffer-string

* lisp/net/tramp.el (tramp-get-buffer-string): Check, that BUFFER
is really a bufferp.

diff --git a/lisp/net/tramp.el b/lisp/net/tramp.el
index b46eeb8e3740a781a5856f44cf4c7956871c8314..20678ec8d1ac0befc1475bd65f4902e92ed88813 100644 (file)
--- a/lisp/net/tramp.el
+++ b/lisp/net/tramp.el
@@ -1960,8 +1960,11 @@ version, the function does nothing."
   "Return contents of BUFFER.
 If BUFFER is not a buffer or a buffer name, return the contents
 of `current-buffer'."
-  (with-current-buffer (or buffer (current-buffer))
-    (substring-no-properties (buffer-string))))
+  (or (let ((buf (or buffer (current-buffer))))
+        (when (bufferp buf)
+          (with-current-buffer (or buffer (current-buffer))
+           (substring-no-properties (buffer-string)))))
+      ""))
 
 (defun tramp-debug-buffer-name (vec)
   "A name for the debug buffer for VEC."