--- a/mercurial/copies.py	Wed Oct 10 00:50:34 2018 +0200
+++ b/mercurial/copies.py	Wed Oct 10 00:50:35 2018 +0200
@@ -139,7 +139,7 @@
     for f in fctx.ancestors():
         if am.get(f.path(), None) == f.filenode():
             return f
-        if limit >= 0 and f.linkrev() < limit and f.rev() < limit:
+        if limit >= 0 and not f.isintroducedafter(limit):
             return None
 
 def _dirstatecopies(d, match=None):