def test_dividing_by_zero(self, firstValue, secondValue, firstUnit, secondUnit):
		value_a = TypedValue(firstValue, firstUnit)
		value_b = TypedValue(secondValue, secondUnit)

		try:
			value_a.divide(value_b)
		except ZeroDivisionError:
			pass
		else:
			self.fail("expected a ZeroDivisionError")		
	def test_dividing_different_units(self, firstValue, secondValue, firstUnit, secondUnit):
		value_a = TypedValue(firstValue, firstUnit)
		value_b = TypedValue(secondValue, secondUnit)

		result = value_a.divide(value_b)
		assert_that(result.unit, equal_to(firstUnit + "/" + secondUnit))
		assert_that(result.value, equal_to(firstValue / secondValue))