def test_add(self):
node = Tree('a')
child = Tree('b')
node.add(child)
self.assertEqual(1, node.child_count())
self.assertEqual(child.parent, node)
self.assertEqual(0, child.idx)
def test_list_add(self):
node = Tree('a')
child = Tree('b')
child2 = Tree('c')
node.add(child, child2)
self.assertEqual(2, node.child_count())