def test_repoint_missing_node():
comp = Computation()
comp.add_node('a')
comp.add_node('b', lambda a: a + 1)
comp.insert('a', 1)
comp.repoint('a', 'new_a')
assert comp.s.new_a == States.PLACEHOLDER
def test_repoint():
comp = Computation()
comp.add_node('a')
comp.add_node('b', lambda a: a + 1)
comp.insert('a', 1)
comp.compute_all()
assert comp.v.b == 2
comp.add_node('5a', lambda a: 5 * a)
comp.repoint('a', '5a')
comp.compute_all()
assert comp.v.b == 5 * 1 + 1