mercurial/repoview.py

--- a/mercurial/repoview.py	Tue Nov 05 14:00:46 2019 -0800
+++ b/mercurial/repoview.py	Tue Nov 05 14:06:11 2019 -0800
@@ -221,6 +221,12 @@
 def wrapchangelog(unfichangelog, filteredrevs):
     cl = copy.copy(unfichangelog)
     cl.filteredrevs = filteredrevs
+
+    class filteredchangelog(cl.__class__):
+        pass
+
+    cl.__class__ = filteredchangelog
+
     return cl