--- a/mercurial/narrowspec.py	Tue Feb 23 22:55:26 2021 -0800
+++ b/mercurial/narrowspec.py	Tue Feb 23 22:58:30 2021 -0800
@@ -329,7 +329,6 @@
     trackeddirty = status.modified + status.added
     clean = status.clean
     if assumeclean:
-        assert not trackeddirty
         clean.extend(lookup)
     else:
         trackeddirty.extend(lookup)