diff --git a/hgext/narrow/__init__.py b/hgext/narrow/__init__.py
--- a/hgext/narrow/__init__.py
+++ b/hgext/narrow/__init__.py
@@ -71,7 +71,7 @@
 
 def reposetup(ui, repo):
     """Wraps local repositories with narrow repo support."""
-    if not isinstance(repo, localrepo.localrepository):
+    if not repo.local():
         return
 
     narrowrepo.wraprepo(repo)