public void ShouldGetDepthFirstUpwards() { _treeWalker = new TreeWalker <TreeNode>(5, new Tree(3)); var actual = _treeWalker.GetAncestorsDepthFirst(5).Select(i => i.Value).ToList(); CollectionAssert.AreEqual( new List <int> { 4, 8, 9, 2, 3, 6, 12, 13, 7, 14, 15, 1 }, actual, string.Join(", ", actual)); }