def test_subtract_letters_from_letters(self):
with self.assertRaises(
TypeError,
msg=
"Test failed, TypeError not raised when subtracting (\"def\",\"abc\") is called"
):
Calculator.subtract("def", "abc")
def test_subtract_decimals(self):
difference = abs(Calculator.subtract(3.8, 3.5) - 0.3)
self.assertLessEqual(difference, 0.001, "Test failed, subtracting (3.8,3.5) should less than or equal 0.3")
def test_subtract_none(self):
self.assertEqual(Calculator.subtract(3, None), 3, "Test failed, subtracting (3,None) should equal 3")
def test_subtract_positive(self):
self.assertEqual(Calculator.subtract(3, 5), -2, "Test failed, subtracting (3,5) should equal -2")
