From 3546b9f06d5a3e3df57ae1fa711371fd401c1914 Mon Sep 17 00:00:00 2001
From: Simon Cozens <simon@simon-cozens.org>
Date: Wed, 3 Jul 2024 13:44:30 +0100
Subject: [PATCH] Search the object's MRO for visitors

---
 Lib/fontTools/misc/visitor.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/Lib/fontTools/misc/visitor.py b/Lib/fontTools/misc/visitor.py
index d289895467..6de432ef93 100644
--- a/Lib/fontTools/misc/visitor.py
+++ b/Lib/fontTools/misc/visitor.py
@@ -61,9 +61,10 @@ def _visitorsFor(celf, thing, _default={}):
             if _visitors is None:
                 break
 
-            m = celf._visitors.get(typ, None)
-            if m is not None:
-                return m
+            for base in typ.mro():
+                m = celf._visitors.get(base, None)
+                if m is not None:
+                    return m
 
         return _default