master c033bb8: Fix :match function for the file widget

[Lars Ingebrigtsen]

branch: master
commit c033bb8648dc6fc14c96925710d662dbcd214cc7
Author: Mauro Aranda <maurooaranda@gmail.com>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Fix :match function for the file widget
    
    * lisp/wid-edit.el (file widget): Return nil if value is not a
    string (bug#25678).
---
 lisp/wid-edit.el | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lisp/wid-edit.el b/lisp/wid-edit.el
index e9799dc..bc2afc6 100644
--- a/lisp/wid-edit.el
+++ b/lisp/wid-edit.el
@@ -3162,8 +3162,9 @@ It reads a file name from an editable text field."
                 #'completion-file-name-table
                 (not read-file-name-completion-ignore-case))
   :match (lambda (widget value)
-           (or (not (widget-get widget :must-match))
-               (file-exists-p value)))
+           (and (stringp value)
+                (or (not (widget-get widget :must-match))
+                    (file-exists-p value))))
   :validate (lambda (widget)
               (let ((value (widget-value widget)))
                 (unless (widget-apply widget :match value)