--- a/tests/test-narrow.t	Tue Apr 05 12:06:32 2022 -0700
+++ b/tests/test-narrow.t	Tue Apr 12 19:40:37 2022 +0100
@@ -71,6 +71,17 @@
   updating to branch default
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
+The "narrow" repo requirement is ignored by [debugupgraderepo]
+
+#if tree
+  $ (cd should-work; hg debugupgraderepo)
+  abort: cannot upgrade repository; unsupported source requirement: treemanifest
+  [255]
+#else
+  $ (cd should-work; hg debugupgraderepo | grep 'no format upgrades found in existing repository')
+  (no format upgrades found in existing repository)
+#endif
+
 Test repo with local changes
   $ hg clone --narrow ssh://user@dummy/master narrow-local-changes --include d0 --include d3 --include d6
   requesting all changes