import unittest

from grains import square, total

# Tests adapted from `problem-specifications//canonical-data.json` @ v1.2.0

class GrainsTest(unittest.TestCase):

def test_1(self):

self.assertEqual(square(1), 1)

def test_2(self):

self.assertEqual(square(2), 2)

def test_3(self):

self.assertEqual(square(3), 4)

def test_4(self):

self.assertEqual(square(4), 8)

def test_16(self):

self.assertEqual(square(16), 32768)

def test_32(self):

self.assertEqual(square(32), 2147483648)

def test_64(self):

self.assertEqual(square(64), 9223372036854775808)

def test_square_0_raises_an_exception(self):

with self.assertRaisesWithMessage(ValueError):

square(0)

def test_negative_square_raises_an_exception(self):

with self.assertRaisesWithMessage(ValueError):

square(-1)

def test_square_greater_than_64_raises_an_exception(self):

with self.assertRaisesWithMessage(ValueError):

square(65)

def test_returns_the_total_number_of_grains_on_the_board(self):

self.assertEqual(total(), 18446744073709551615)

# Utility functions

def assertRaisesWithMessage(self, exception):

return self.assertRaisesRegex(exception, r".+")

if __name__ == "__main__":

unittest.main()