test-log: test that fctx.ancestors() can't index parents only by linkrev This covers a possible bug that could be caused by the following change: --- a/mercurial/context.py +++ b/mercurial/context.py @@ -1047,7 +1047,7 @@ class basefilectx(object): while True: for parent in c.parents()[:cut]: - visit[(parent.linkrev(), parent.filenode())] = parent + visit[parent.linkrev()] = parent if not visit: break c = visit.pop(max(visit))