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
|
require "spec_helper"
require "hamster/list"
describe Hamster::List do
describe "#insert" do
let(:original) { L[1, 2, 3] }
it "can add items at the beginning of a list" do
list = original.insert(0, :a, :b)
list.size.should be(5)
list.at(0).should be(:a)
list.at(2).should be(1)
end
it "can add items in the middle of a list" do
list = original.insert(1, :a, :b, :c)
list.size.should be(6)
list.to_a.should == [1, :a, :b, :c, 2, 3]
end
it "can add items at the end of a list" do
list = original.insert(3, :a, :b, :c)
list.size.should be(6)
list.to_a.should == [1, 2, 3, :a, :b, :c]
end
it "can add items past the end of a list" do
list = original.insert(6, :a, :b)
list.size.should be(8)
list.to_a.should == [1, 2, 3, nil, nil, nil, :a, :b]
end
it "accepts a negative index, which counts back from the end of the list" do
list = original.insert(-2, :a)
list.size.should be(4)
list.to_a.should == [1, :a, 2, 3]
end
it "raises IndexError if a negative index is too great" do
expect { original.insert(-4, :a) }.to raise_error(IndexError)
end
it "is lazy" do
-> { Hamster.stream { fail }.insert(0, :a) }.should_not raise_error
end
end
end
|
