diff --git a/mercurial/scmutil.py b/mercurial/scmutil.py
--- a/mercurial/scmutil.py
+++ b/mercurial/scmutil.py
@@ -1431,8 +1431,8 @@
     """
     oldctx = repo[b'.']
     ds = repo.dirstate
+    copies = dict(ds.copies())
     ds.setparents(newctx.node(), nullid)
-    copies = dict(ds.copies())
     s = newctx.status(oldctx, match=match)
     for f in s.modified:
         if ds[f] == b'r':