File: random.rb

package info (click to toggle)
mruby 3.4.0-2
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 5,584 kB
  • sloc: ansic: 51,933; ruby: 29,510; yacc: 7,077; cpp: 517; makefile: 51; sh: 42
file content (137 lines) | stat: -rw-r--r-- 3,478 bytes parent folder | download
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
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
##
# Random Test

assert("Random.new") do
  r1 = Random.new(123)
  r2 = Random.new(123)
  r3 = Random.new(124)
  assert_equal(r1.rand, r2.rand)
  assert_not_equal(r1.rand, r3.rand)
end

assert("Kernel#srand") do
  srand(234)
  r1 = rand
  srand(234)
  r2 = rand
  srand(235)
  r3 = rand
  assert_equal(r1, r2)
  assert_not_equal(r1, r3)
end

assert("Random.srand") do
  Random.srand(345)
  r1 = rand
  srand(345)
  r2 = Random.rand
  Random.srand(346)
  r3 = rand
  assert_equal(r1, r2)
  assert_not_equal(r1, r3)
end

assert("Random#bytes") do
  r = Random.new(10)
  num = 11
  a = r.bytes(num)
  assert_kind_of String, a
  assert_equal num, a.bytesize
  b = r.bytes(num)
  assert_kind_of String, b
  assert_equal num, b.bytesize
  assert_not_equal a, b
  b = r.bytes(num / 2)
  assert_equal num / 2, b.bytesize
end

assert("return class of Kernel#rand") do
  assert_kind_of(Integer, rand(3))
  assert_kind_of(Integer, rand(1.5))
  skip unless Object.const_defined?(:Float)
  assert_kind_of(Float, rand)
  assert_kind_of(Float, rand(0.5))
end

assert("Array#shuffle") do
  orig = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
  ary = orig.dup
  shuffled = ary.shuffle
  assert_equal(orig, ary)
  assert_not_equal(ary, shuffled)
  assert_equal(orig, shuffled.sort)
end

assert('Array#shuffle!') do
  orig = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
  ary = orig.dup
  assert_same(ary, ary.shuffle!)
  assert_not_equal(orig, ary)
  assert_equal(orig, ary.sort)
end

assert("Array#shuffle(random)") do
  assert_raise(TypeError) do
    # this will cause an exception due to the wrong argument
    [1, 2].shuffle(random: "Not a Random instance")
  end

  # verify that the same seed causes the same results
  ary = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
  shuffled1 = ary.shuffle(random: Random.new(345))
  shuffled2 = ary.shuffle(random: Random.new(345))
  shuffled3 = ary.shuffle(random: Random.new(346))
  assert_equal(shuffled1, shuffled2)
  assert_not_equal(shuffled1, shuffled3)
end

assert('Array#shuffle!(random)') do
  assert_raise(TypeError) do
    # this will cause an exception due to the wrong argument
    [1, 2].shuffle!(random: "Not a Random instance")
  end

  # verify that the same seed causes the same results
  ary1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
  ary1.shuffle!(random: Random.new(345))
  ary2 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
  ary2.shuffle!(random: Random.new(345))
  ary3 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
  ary3.shuffle!(random: Random.new(346))
  assert_equal(ary1, ary2)
  assert_not_equal(ary1, ary3)
end

assert('Array#sample') do
  100.times do
    assert_include([0, 1, 2], [2, 1, 0].sample)
    [2, 1, 0].sample(2).each { |sample| assert_include([0, 1, 2], sample) }
    h = {}
    (1..10).to_a.sample(7).each do |sample|
      assert_not_include(h, sample)
      h[sample] = true
    end
  end

  assert_nil([].sample)
  assert_equal([], [].sample(1))
  assert_equal([], [2, 1].sample(0))
  assert_raise(TypeError) { [2, 1].sample(true) }
  assert_raise(ArgumentError) { [2, 1].sample(-1) }
end

assert('Array#sample(random)') do
  assert_raise(TypeError) do
    # this will cause an exception due to the wrong argument
    [1, 2].sample(2, random: "Not a Random instance")
  end

  # verify that the same seed causes the same results
  ary = (1..10).to_a
  srand(15)
  samples1 = ary.sample(4)
  samples2 = ary.sample(4, random: Random.new(15))
  samples3 = ary.sample(4, random: Random.new(16))
  assert_equal(samples1, samples2)
  assert_not_equal(samples1, samples3)
end