notmuch.el: convert sparse keymap to a list in notmuch-substitute-one-command-key-with-prefix

The previous version would crash when a key was bound to a sparse
keymap, since apparently these are not straightforward lists.  The
usage of map-keymap is a bit obscure: it only has side-effects, no
return value.

1 files changed, 6 insertions, 2 deletions

diff --git a/notmuch.el b/notmuch.el
index 342ce6ab..82471b57 100644
--- a/notmuch.el
+++ b/notmuch.el
@@ -1000,8 +1000,12 @@ For a mouse binding, return nil."
     (if (mouse-event-p key)
 	nil
       (if (keymapp action)
-	  (let ((substitute (apply-partially 'notmuch-substitute-one-command-key-with-prefix (notmuch-prefix-key-description key))))
-	    (mapconcat substitute (cdr action) "\n"))
+	  (let ((substitute (apply-partially 'notmuch-substitute-one-command-key-with-prefix (notmuch-prefix-key-description key)))
+		(as-list))
+	    (map-keymap (lambda (a b)
+			  (push (cons a b) as-list))
+			action)
+	    (mapconcat substitute as-list "\n"))
 	(concat prefix (format-kbd-macro (vector key))
 		"\t"
 		(notmuch-documentation-first-line action))))))