exercism-solution/python/simple-linked-list/simple_linked_list_test.py at master · fruit-in/exercism-solution · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
import unittest

from simple_linked_list import LinkedList, EmptyListException


# No canonical data available for this exercise

class SimpleLinkedListTest(unittest.TestCase):
    def test_empty_list_has_len_zero(self):
        sut = LinkedList()
        self.assertEqual(len(sut), 0)

    def test_singleton_list_has_len_one(self):
        sut = LinkedList([1])
        self.assertEqual(len(sut), 1)

    def test_non_empty_list_has_correct_len(self):
        sut = LinkedList([1, 2, 3])
        self.assertEqual(len(sut), 3)

    def test_error_on_empty_list_head(self):
        sut = LinkedList()
        with self.assertRaisesWithMessage(EmptyListException):
            sut.head()

    def test_singleton_list_has_head(self):
        sut = LinkedList([1])
        self.assertEqual(sut.head().value(), 1)

    def test_non_empty_list_has_correct_head(self):
        sut = LinkedList([1, 2])
        self.assertEqual(sut.head().value(), 2)

    def test_can_push_to_non_empty_list(self):
        sut = LinkedList([1, 2, 3])
        sut.push(4)
        self.assertEqual(len(sut), 4)

    def test_pushing_to_empty_list_changes_head(self):
        sut = LinkedList()
        sut.push(5)
        self.assertEqual(len(sut), 1)
        self.assertEqual(sut.head().value(), 5)

    def test_can_pop_from_non_empty_list(self):
        sut = LinkedList([3, 4, 5])
        self.assertEqual(sut.pop(), 5)
        self.assertEqual(len(sut), 2)
        self.assertEqual(sut.head().value(), 4)

    def test_pop_from_singleton_list_removes_head(self):
        sut = LinkedList([1])
        self.assertEqual(sut.pop(), 1)
        with self.assertRaisesWithMessage(EmptyListException):
            sut.head()

    def test_error_on_empty_list_pop(self):
        sut = LinkedList()
        with self.assertRaisesWithMessage(EmptyListException):
            sut.pop()

    def test_push_and_pop(self):
        sut = LinkedList([1, 2])
        sut.push(3)
        self.assertEqual(len(sut), 3)
        self.assertEqual(sut.pop(), 3)
        self.assertEqual(sut.pop(), 2)
        self.assertEqual(sut.pop(), 1)
        self.assertEqual(len(sut), 0)
        sut.push(4)
        self.assertEqual(len(sut), 1)
        self.assertEqual(sut.head().value(), 4)

    def test_singleton_list_head_has_no_next(self):
        sut = LinkedList([1])
        self.assertIsNone(sut.head().next())

    def test_non_empty_list_traverse(self):
        sut = LinkedList(range(10))
        current = sut.head()
        for i in range(10):
            self.assertEqual(current.value(), 9 - i)
            current = current.next()
        self.assertIsNone(current)

    def test_empty_linked_list_to_list_is_empty(self):
        sut = LinkedList()
        self.assertEqual(list(sut), [])

    def test_singleton_linked_list_to_list_list_with_singular_element(self):
        sut = LinkedList([1])
        self.assertEqual(list(sut), [1])

    def test_non_empty_linked_list_to_list_is_list_with_all_elements(self):
        sut = LinkedList([1, 2, 3])
        self.assertEqual(list(sut), [3, 2, 1])

    def test_reversed_empty_list_is_empty_list(self):
        sut = LinkedList([])
        self.assertEqual(list(sut.reversed()), [])

    def test_reversed_singleton_list_is_same_list(self):
        sut = LinkedList([1])
        self.assertEqual(list(sut.reversed()), [1])

    def test_reverse_non_empty_list(self):
        sut = LinkedList([1, 2, 3])
        self.assertEqual(list(sut.reversed()), [1, 2, 3])

    # Utility functions
    def assertRaisesWithMessage(self, exception):
        return self.assertRaisesRegex(exception, r".+")


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