"""DEMO regression tests for the fixed calculation."""

import unittest

from fixed_demo import discounted_total


class DiscountedTotalTests(unittest.TestCase):
    def test_percentage_is_applied_to_subtotal(self):
        self.assertEqual(discounted_total(250, 10), 225)

    def test_full_discount_is_zero(self):
        self.assertEqual(discounted_total(80, 100), 0)

    def test_invalid_percent_is_rejected(self):
        with self.assertRaises(ValueError):
            discounted_total(80, 101)


if __name__ == "__main__":
    unittest.main()