py3: fix copy tracing

Summary: filter returns a generator in Python 3, but we need a list.

Reviewed By: singhsrb

Differential Revision: D23720661

fbshipit-source-id: 8de3f5844bfe8b85b37c44423733fd2a09967397

eden/scm/edenscm/mercurial/copies.py

@@ -123,7 +123,7 @@ def _chain(src, dst, a, b):
             t[k] = v
 
     # remove criss-crossed copies
-    for k, v in t.items():
+    for k, v in list(t.items()):
         if k in src and v in dst:
             del t[k]
 

eden/scm/tests/test-copytrace-manual-t.py

@@ -8,9 +8,6 @@ from __future__ import absolute_import
 from testutil.dott import feature, sh, testtmp  # noqa: F401
 
 
-feature.require(["py2"])
-
-
 sh % "enable rebase"
 sh % "newrepo"
 sh % "drawdag" << r"""