def test_error_result_for_largest_if_min_is_more_than_max(self):
with self.assertRaisesWithMessage(ValueError):
value, factors = largest(min_factor=2, max_factor=1)
def test_find_the_largest_palindrome_from_four_digit_factors(self):
value, factors = largest(min_factor=1000, max_factor=9999)
self.assertEqual(value, 99000099)
self.assertFactorsEqual(factors, [[9901, 9999]])
def test_empty_result_for_largest_if_no_palindrome_in_the_range(self):
value, factors = largest(min_factor=15, max_factor=15)
self.assertIsNone(value)
self.assertFactorsEqual(factors, [])
def test_find_the_largest_palindrome_from_triple_digit_factors(self):
value, factors = largest(min_factor=100, max_factor=999)
self.assertEqual(value, 906609)
self.assertFactorsEqual(factors, [[913, 993]])
def test_finds_the_largest_palindrome_from_single_digit_factors(self):
value, factors = largest(min_factor=1, max_factor=9)
self.assertEqual(value, 9)
self.assertFactorsEqual(factors, [[1, 9], [3, 3]])
def test_error_for_largest_palindrome_if_min_is_more_than_max(self):
with self.assertRaisesWithMessage(ValueError):
# value, factors = largest(min_factor=2, max_factor=1)
largest(min_factor=2, max_factor=1)
def test_largest_palindrome_from_double_digit_factors(self):
value, factors = largest(min_factor=10, max_factor=99)
self.assertEqual(value, 9009)
self.assertFactorsEqual(factors, [[91, 99]])
def test_error_result_for_largest_if_min_is_more_than_max(self):
with self.assertRaises(ValueError) as err:
value, factors = largest(min_factor=2, max_factor=1)
self.assertEqual(type(err.exception), ValueError)
self.assertEqual(err.exception.args[0], "min must be <= max")
