--- a/mercurial/changegroup.py	Mon Aug 27 10:15:15 2018 -0700
+++ b/mercurial/changegroup.py	Wed Aug 15 16:50:44 2018 +0000
@@ -1065,7 +1065,7 @@
             tree, nodes = tmfnodes.popitem()
             store = mfl.getstorage(tree)
 
-            if not self._filematcher.visitdir(store._tree[:-1] or '.'):
+            if not self._filematcher.visitdir(store.tree[:-1] or '.'):
                 prunednodes = []
             else:
                 frev, flr = store.rev, store.linkrev