exercism/python/black-jack/black_jack_test.py

import unittest
import pytest

from black_jack import (
                        value_of_card,
                        higher_card,
                        value_of_ace,
                        is_blackjack,
                        can_split_pairs,
                        can_double_down
                        )


class BlackJackTest(unittest.TestCase):

    @pytest.mark.task(taskno=1)
    def test_value_of_card(self):
        test_data = [('2', 2), ('5', 5), ('8', 8),
                     ('A', 1), ('10', 10), ('J', 10),
                     ('Q', 10), ('K', 10)]

        for variant, (card, expected) in enumerate(test_data, 1):
            with self.subTest(f'variation #{variant}', card=card, expected=expected):
                actual_result = value_of_card(card)
                error_msg = (f'Called value_of_card({card}). '
                             f'The function returned {actual_result} as the value of the {card} card, '
                             f'but the test expected {expected} as the {card} card value.')

                self.assertEqual(actual_result, expected, msg=error_msg)


    @pytest.mark.task(taskno=2)
    def test_higher_card(self):
        test_data = [('A', 'A', ('A', 'A')),
                     ('10', 'J', ('10', 'J')),
                     ('3', 'A', '3'),
                     ('3', '6', '6'),
                     ('Q', '10', ('Q', '10')),
                     ('4', '4', ('4', '4')),
                     ('9',  '10', '10'),
                     ('6', '9', '9'),
                     ('4', '8', '8')]

        for variant, (card_one, card_two, expected) in enumerate(test_data, 1):
            with self.subTest(f'variation #{variant}', card_one=card_one, card_two=card_two, expected=expected):
                actual_result = higher_card(card_one, card_two)
                error_msg = (f'Called higher_card({card_one}, {card_two}). '
                             f'The function returned {actual_result}, '
                             f'but the test expected {expected} as the result for the cards {card_one, card_two}.')

                self.assertEqual(actual_result, expected, msg=error_msg)

    @pytest.mark.task(taskno=3)
    def test_value_of_ace(self):
        test_data = [('2', '3', 11), ('3', '6', 11), ('5', '2', 11),
                     ('8', '2', 11), ('5', '5', 11), ('Q', 'A', 1),
                     ('10', '2', 1), ('7', '8', 1), ('J', '9', 1),
                     ('K', 'K', 1), ('2', 'A', 1), ('A', '2', 1)]

        for variant, (card_one, card_two, ace_value) in enumerate(test_data, 1):
            with self.subTest(f'variation #{variant}', card_one=card_one, card_two=card_two, ace_value=ace_value):
                actual_result = value_of_ace(card_one, card_two)
                error_msg = (f'Called value_of_ace({card_one}, {card_two}). '
                             f'The function returned {actual_result}, '
                             f'but the test expected {ace_value} as the value of an ace card '
                             f'when the hand includes {card_one, card_two}.')

                self.assertEqual(value_of_ace(card_one, card_two), ace_value, msg=error_msg)

    @pytest.mark.task(taskno=4)
    def test_is_blackjack(self):
        test_data = [(('A', 'K'), True), (('10', 'A'), True),
                     (('10', '9'), False), (('A', 'A'), False),
                     (('4', '7'), False), (('9', '2'), False),
                     (('Q', 'K'), False)]

        for variant, (hand, expected) in enumerate(test_data, 1):
            with self.subTest(f'variation #{variant}', hand=hand, expected=expected):
                actual_result = is_blackjack(*hand)
                error_msg = (f'Called is_blackjack({hand[0]}, {hand[1]}). '
                             f'The function returned {actual_result}, '             
                             f'but hand {hand} {"is" if expected else "is not"} a blackjack.')

                self.assertEqual(actual_result, expected, msg=error_msg)

    @pytest.mark.task(taskno=5)
    def test_can_split_pairs(self):
        test_data = [(('Q', 'K'), True), (('6', '6'), True),
                     (('A', 'A'), True),(('10', 'A'), False),
                     (('10', '9'), False)]

        for variant, (hand, expected) in enumerate(test_data, 1):
            with self.subTest(f'variation #{variant}', input=hand, expected=expected):
                actual_result = can_split_pairs(*hand)
                error_msg = (f'Called can_split_pairs({hand[0]}, {hand[1]}). '
                             f'The function returned {actual_result}, '
                             f'but hand {hand} {"can" if expected else "cannot"} be split into pairs.')

                self.assertEqual(actual_result, expected, msg=error_msg)

    @pytest.mark.task(taskno=6)
    def test_can_double_down(self):
        test_data = [(('A', '9'), True), (('K', 'A'), True),
                     (('4', '5'), True),(('A', 'A'), False),
                     (('10', '2'), False), (('10', '9'), False)]

        for variant, (hand, expected) in enumerate(test_data, 1):
            with self.subTest(f'variation #{variant}', hand=hand, expected=expected):
                actual_result = can_double_down(*hand)
                error_msg = (f'Called can_double_down({hand[0]}, {hand[1]}). '
                             f'The function returned {actual_result}, '
                             f'but hand {hand} {"can" if expected else "cannot"} be doubled down.')

                self.assertEqual(actual_result, expected, msg=error_msg)