xref--find-ignores-arguments: Return "" if IGNORES is nil

diff --git a/lisp/progmodes/xref.el b/lisp/progmodes/xref.el
index c7f015b94f03014e656a09cea12d992d80f34542..bf999aeb0d1fadf8b793e718d702e0f09fb6c465 100644 (file)
--- a/lisp/progmodes/xref.el
+++ b/lisp/progmodes/xref.el
@@ -1064,7 +1064,8 @@ IGNORES is a list of glob patterns."
 IGNORES is a list of glob patterns.  DIR is an absolute
 directory, used as the root of the ignore globs."
   (cl-assert (not (string-match-p "\\`~" dir)))
-  (when ignores
+  (if (not ignores)
+      ""
     (concat
      (shell-quote-argument "(")
      " -path "