Resilience against recursive customization groups

I’m seeing this group cycle: (magit-popups magit-popup convenience emacs), which was causing an infinite recursion.

1 files changed, 11 insertions, 6 deletions

diff --git a/initsplit.el b/initsplit.el
index 9e45b84..aea6002 100644
--- a/initsplit.el
+++ b/initsplit.el
@@ -221,17 +221,22 @@ of the filename as with `load-library'."
            (initsplit-strip-lisp-suffix
             (initsplit-filename filespec))))
 
-(defun initsplit-find-option-match (pattern options)
+(defun initsplit-find-option-match (pattern options &optional visited)
   "Where OPTIONS are an alist as accepted by
 `custom-buffer-create', return nil unless they specify
-customization of a symbol whose name matches PATTERN."
+customization of a symbol whose name matches PATTERN.  The
+optional VISITED parameter is for internal use only and should
+always be nil when this function is not called recursively."
   (find-if 
    (lambda (option)
-     (if (eq (cadr option) 'custom-group)
-         (initsplit-find-option-match pattern (custom-group-members (car option) nil))
-       (string-match pattern (symbol-name (car option)))))
+     (let ((x (car option)))
+       (if (eq (cadr option) 'custom-group)
+           (if (memq x visited)
+               (message "group cycle: %s" visited)
+             (initsplit-find-option-match pattern (custom-group-members x nil) (cons x visited)))
+         (string-match pattern (symbol-name x)))))
    options))
-  
+
 (defadvice custom-buffer-create-internal
   (before initsplit-custom-buffer-create-internal
           (options &optional description) activate compile preactivate)