def test_add_empty_returns_zero() -> None: assert Calc.ADD("") == 0
def test_add_1_returns_1() -> None: assert Calc.ADD("1") == 1
def test_add_negative_returns_error() -> None: assert Calc.ADD("2,-4,3,-5") == "Negatives not allowed: -4,-5"
def test_add_greater1000_returns_sum() -> None: assert Calc.ADD("1001,2") == 2
def test_add_newline_returns_sum() -> None: assert Calc.ADD("1\n2,3") == 6
def test_add_morenumbers_returns_sum() -> None: assert Calc.ADD("1,2,3,4,5") == 15
def test_add_twonumbers_returns_sum() -> None: assert Calc.ADD("1,2") == 3