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
|
require 'spec_helper'
describe Immutable::Vector do
describe '#shuffle' do
let(:vector) { V[1,2,3,4] }
it 'returns the same values, in a usually different order' do
different = false
10.times do
shuffled = vector.shuffle
shuffled.sort.should eql(vector)
different ||= (shuffled != vector)
end
different.should be(true)
end
it 'leaves the original unchanged' do
vector.shuffle
vector.should eql(V[1,2,3,4])
end
context 'from a subclass' do
it 'returns an instance of the subclass' do
subclass = Class.new(Immutable::Vector)
instance = subclass.new([1,2,3])
instance.shuffle.class.should be(subclass)
end
end
[32, 33, 1023, 1024, 1025].each do |size|
context "on a #{size}-item vector" do
it 'works correctly' do
vector = V.new(1..size)
shuffled = vector.shuffle
shuffled = vector.shuffle while shuffled.eql?(vector) # in case we get the same
vector.should eql(V.new(1..size))
shuffled.size.should == vector.size
shuffled.sort.should eql(vector)
end
end
end
end
end
|
