String oldHead = head;
Assert.assertEquals(null, index.getPath("1", head));
head = mk.commit("/", "+\"test\" : {\"id\":\"1\"}", head, null);
head = mk.commit("/", "+\"test2\" : {\"id\":\"2\"}", head, null);
Assert.assertEquals("/test", index.getPath("1", head));
Assert.assertEquals("/test2", index.getPath("2", head));
Assert.assertEquals("/test", index.getPath("1", oldHead));