def test_getSetPrimitiveProperties():
number = Number(20)
assert number.value == 20
assert number.double_value == 40
assert Negate(Add(Number(20), Number(10))).value == -30
assert Multiply(Add(Number(5), Number(5)), Number(2)).value == 20
assert Power(Number(3), Number(4)).value == 3 ** 4
assert Power(Number(999), Number(1)).value == 999
assert Power(Number(999), Number(0)).value == 1
def test_unionProperties():
calc3 = Calculator()
calc3.union_property = Multiply(Number(9), Number(3))
assert isinstance(calc3.union_property, Multiply)
assert calc3.read_union_value() == 9 * 3
calc3.union_property = Power(Number(10), Number(3))
assert isinstance(calc3.union_property, Power)
assert calc3.read_union_value() == 10 ** 3