|
2 | 2 | require_relative 'circular_buffer' |
3 | 3 |
|
4 | 4 | class CircularBufferTest < Minitest::Test |
5 | | - def test_read_empty_buffer_throws_buffer_empty_exception |
| 5 | + def test_reading_empty_buffer_should_fail |
| 6 | + # skip |
6 | 7 | buffer = CircularBuffer.new(1) |
7 | 8 | assert_raises(CircularBuffer::BufferEmptyException) { buffer.read } |
8 | 9 | end |
9 | 10 |
|
10 | | - def test_write_and_read_back_one_item |
| 11 | + def test_can_read_an_item_just_written |
11 | 12 | skip |
12 | 13 | buffer = CircularBuffer.new(1) |
13 | | - buffer.write '1' |
| 14 | + buffer.write('1') |
14 | 15 | assert_equal '1', buffer.read |
15 | | - assert_raises(CircularBuffer::BufferEmptyException) { buffer.read } |
16 | 16 | end |
17 | 17 |
|
18 | | - def test_write_and_read_back_multiple_items |
| 18 | + def test_each_item_may_only_be_read_once |
19 | 19 | skip |
20 | | - buffer = CircularBuffer.new(2) |
21 | | - buffer.write '1' |
22 | | - buffer.write '2' |
| 20 | + buffer = CircularBuffer.new(1) |
| 21 | + buffer.write('1') |
23 | 22 | assert_equal '1', buffer.read |
24 | | - assert_equal '2', buffer.read |
25 | 23 | assert_raises(CircularBuffer::BufferEmptyException) { buffer.read } |
26 | 24 | end |
27 | 25 |
|
28 | | - def test_clearing_buffer |
| 26 | + def test_items_are_read_in_the_order_they_are_written |
29 | 27 | skip |
30 | | - buffer = CircularBuffer.new(3) |
31 | | - ('1'..'3').each { |i| buffer.write i } |
32 | | - buffer.clear |
33 | | - assert_raises(CircularBuffer::BufferEmptyException) { buffer.read } |
34 | | - buffer.write '1' |
35 | | - buffer.write '2' |
| 28 | + buffer = CircularBuffer.new(2) |
| 29 | + buffer.write('1') |
| 30 | + buffer.write('2') |
36 | 31 | assert_equal '1', buffer.read |
37 | | - buffer.write '3' |
38 | 32 | assert_equal '2', buffer.read |
39 | 33 | end |
40 | 34 |
|
41 | | - def test_alternate_write_and_read |
| 35 | + def test_full_buffer_cant_be_written_to |
42 | 36 | skip |
43 | | - buffer = CircularBuffer.new(2) |
44 | | - buffer.write '1' |
| 37 | + buffer = CircularBuffer.new(1) |
| 38 | + buffer.write('1') |
| 39 | + assert_raises(CircularBuffer::BufferFullException) { buffer.write('2') } |
| 40 | + end |
| 41 | + |
| 42 | + def test_a_read_frees_up_capacity_for_another_write |
| 43 | + skip |
| 44 | + buffer = CircularBuffer.new(1) |
| 45 | + buffer.write('1') |
45 | 46 | assert_equal '1', buffer.read |
46 | | - buffer.write '2' |
| 47 | + buffer.write('2') |
47 | 48 | assert_equal '2', buffer.read |
48 | 49 | end |
49 | 50 |
|
50 | | - def test_reads_back_oldest_item |
| 51 | + def test_read_position_is_maintained_even_across_multiple_writes |
51 | 52 | skip |
52 | 53 | buffer = CircularBuffer.new(3) |
53 | | - buffer.write '1' |
54 | | - buffer.write '2' |
55 | | - buffer.read |
56 | | - buffer.write '3' |
| 54 | + buffer.write('1') |
| 55 | + buffer.write('2') |
| 56 | + assert_equal '1', buffer.read |
| 57 | + buffer.write('3') |
57 | 58 | assert_equal '2', buffer.read |
58 | 59 | assert_equal '3', buffer.read |
59 | 60 | end |
60 | 61 |
|
61 | | - def test_writing_to_a_full_buffer_throws_an_exception |
| 62 | + def test_items_cleared_out_of_buffer_cant_be_read |
62 | 63 | skip |
63 | | - buffer = CircularBuffer.new(2) |
64 | | - buffer.write '1' |
65 | | - buffer.write '2' |
66 | | - assert_raises(CircularBuffer::BufferFullException) { buffer.write 'A' } |
| 64 | + buffer = CircularBuffer.new(1) |
| 65 | + buffer.write('1') |
| 66 | + buffer.clear |
| 67 | + assert_raises(CircularBuffer::BufferEmptyException) { buffer.read } |
67 | 68 | end |
68 | 69 |
|
69 | | - def test_overwriting_oldest_item_in_a_full_buffer |
| 70 | + def test_clear_frees_up_capacity_for_another_write |
70 | 71 | skip |
71 | | - buffer = CircularBuffer.new(2) |
72 | | - buffer.write '1' |
73 | | - buffer.write '2' |
74 | | - buffer.write! 'A' |
| 72 | + buffer = CircularBuffer.new(1) |
| 73 | + buffer.write('1') |
| 74 | + buffer.clear |
| 75 | + buffer.write('2') |
75 | 76 | assert_equal '2', buffer.read |
76 | | - assert_equal 'A', buffer.read |
77 | | - assert_raises(CircularBuffer::BufferEmptyException) { buffer.read } |
78 | 77 | end |
79 | 78 |
|
80 | | - def test_forced_writes_to_non_full_buffer_should_behave_like_writes |
| 79 | + def test_clear_does_nothing_on_empty_buffer |
| 80 | + skip |
| 81 | + buffer = CircularBuffer.new(1) |
| 82 | + buffer.clear |
| 83 | + buffer.write('1') |
| 84 | + assert_equal '1', buffer.read |
| 85 | + end |
| 86 | + |
| 87 | + def test_overwrite_acts_like_write_on_non_full_buffer |
81 | 88 | skip |
82 | 89 | buffer = CircularBuffer.new(2) |
83 | | - buffer.write '1' |
84 | | - buffer.write! '2' |
| 90 | + buffer.write('1') |
| 91 | + buffer.write!('2') |
85 | 92 | assert_equal '1', buffer.read |
86 | 93 | assert_equal '2', buffer.read |
87 | | - assert_raises(CircularBuffer::BufferEmptyException) { buffer.read } |
88 | 94 | end |
89 | 95 |
|
90 | | - def test_alternate_read_and_write_into_buffer_overflow |
| 96 | + def test_overwrite_replaces_the_oldest_item_on_full_buffer |
| 97 | + skip |
| 98 | + buffer = CircularBuffer.new(2) |
| 99 | + buffer.write('1') |
| 100 | + buffer.write('2') |
| 101 | + buffer.write!('3') |
| 102 | + assert_equal '2', buffer.read |
| 103 | + assert_equal '3', buffer.read |
| 104 | + end |
| 105 | + |
| 106 | + def test_overwrite_replaces_the_oldest_item_remaining_in_buffer_following_a_read |
91 | 107 | skip |
92 | | - buffer = CircularBuffer.new(5) |
93 | | - ('1'..'3').each { |i| buffer.write i } |
94 | | - buffer.read |
95 | | - buffer.read |
96 | | - buffer.write '4' |
97 | | - buffer.read |
98 | | - ('5'..'8').each { |i| buffer.write i } |
99 | | - buffer.write! 'A' |
100 | | - buffer.write! 'B' |
101 | | - ('6'..'8').each do |i| |
102 | | - assert_equal i, buffer.read |
103 | | - end |
104 | | - assert_equal 'A', buffer.read |
105 | | - assert_equal 'B', buffer.read |
| 108 | + buffer = CircularBuffer.new(3) |
| 109 | + buffer.write('1') |
| 110 | + buffer.write('2') |
| 111 | + buffer.write('3') |
| 112 | + assert_equal '1', buffer.read |
| 113 | + buffer.write('4') |
| 114 | + buffer.write!('5') |
| 115 | + assert_equal '3', buffer.read |
| 116 | + assert_equal '4', buffer.read |
| 117 | + assert_equal '5', buffer.read |
| 118 | + end |
| 119 | + |
| 120 | + def test_initial_clear_does_not_affect_wrapping_around |
| 121 | + skip |
| 122 | + buffer = CircularBuffer.new(2) |
| 123 | + buffer.clear |
| 124 | + buffer.write('1') |
| 125 | + buffer.write('2') |
| 126 | + buffer.write!('3') |
| 127 | + buffer.write!('4') |
| 128 | + assert_equal '3', buffer.read |
| 129 | + assert_equal '4', buffer.read |
106 | 130 | assert_raises(CircularBuffer::BufferEmptyException) { buffer.read } |
107 | 131 | end |
108 | 132 | end |
0 commit comments