Fix gnus-thread-hide-subtree defcustom

* lisp/gnus/gnus-sum.el (gnus-thread-hide-subtree): Make the
"Non-nil" predicate do what it's supposed to (i.e., return non-nil
on non-nil values (excepting predicates)) (bug#37916).

diff --git a/lisp/gnus/gnus-sum.el b/lisp/gnus/gnus-sum.el
index b5d744843f0097376d418291327e540f95cf7b20..f21bc7584e51ce7cdcf0e6a08e76cb4caaecc35b 100644 (file)
--- a/lisp/gnus/gnus-sum.el
+++ b/lisp/gnus/gnus-sum.el
@@ -334,7 +334,7 @@ If threads are hidden, you have to run the command
   :group 'gnus-thread
   :type '(radio (sexp :format "Non-nil\n"
                      :match (lambda (widget value)
-                              (not (or (consp value) (functionp value))))
+                              (and value (not (functionp value))))
                      :value t)
                (const nil)
                (sexp :tag "Predicate specifier")))