1require_relative '../../spec_helper'
2require_relative 'fixtures/classes'
3
4describe "Array#last" do
5  it "returns the last element" do
6    [1, 1, 1, 1, 2].last.should == 2
7  end
8
9  it "returns nil if self is empty" do
10    [].last.should == nil
11  end
12
13  it "returns the last count elements if given a count" do
14    [1, 2, 3, 4, 5, 9].last(3).should == [4, 5, 9]
15  end
16
17  it "returns an empty array when passed a count on an empty array" do
18    [].last(0).should == []
19    [].last(1).should == []
20  end
21
22  it "returns an empty array when count == 0" do
23    [1, 2, 3, 4, 5].last(0).should == []
24  end
25
26  it "returns an array containing the last element when passed count == 1" do
27    [1, 2, 3, 4, 5].last(1).should == [5]
28  end
29
30  it "raises an ArgumentError when count is negative" do
31    lambda { [1, 2].last(-1) }.should raise_error(ArgumentError)
32  end
33
34  it "returns the entire array when count > length" do
35    [1, 2, 3, 4, 5, 9].last(10).should == [1, 2, 3, 4, 5, 9]
36  end
37
38  it "returns an array which is independent to the original when passed count" do
39    ary = [1, 2, 3, 4, 5]
40    ary.last(0).replace([1,2])
41    ary.should == [1, 2, 3, 4, 5]
42    ary.last(1).replace([1,2])
43    ary.should == [1, 2, 3, 4, 5]
44    ary.last(6).replace([1,2])
45    ary.should == [1, 2, 3, 4, 5]
46  end
47
48  it "properly handles recursive arrays" do
49    empty = ArraySpecs.empty_recursive_array
50    empty.last.should equal(empty)
51
52    array = ArraySpecs.recursive_array
53    array.last.should equal(array)
54  end
55
56  it "tries to convert the passed argument to an Integer usinig #to_int" do
57    obj = mock('to_int')
58    obj.should_receive(:to_int).and_return(2)
59    [1, 2, 3, 4, 5].last(obj).should == [4, 5]
60  end
61
62  it "raises a TypeError if the passed argument is not numeric" do
63    lambda { [1,2].last(nil) }.should raise_error(TypeError)
64    lambda { [1,2].last("a") }.should raise_error(TypeError)
65
66    obj = mock("nonnumeric")
67    lambda { [1,2].last(obj) }.should raise_error(TypeError)
68  end
69
70  it "does not return subclass instance on Array subclasses" do
71    ArraySpecs::MyArray[].last(0).should be_an_instance_of(Array)
72    ArraySpecs::MyArray[].last(2).should be_an_instance_of(Array)
73    ArraySpecs::MyArray[1, 2, 3].last(0).should be_an_instance_of(Array)
74    ArraySpecs::MyArray[1, 2, 3].last(1).should be_an_instance_of(Array)
75    ArraySpecs::MyArray[1, 2, 3].last(2).should be_an_instance_of(Array)
76  end
77
78  it "is not destructive" do
79    a = [1, 2, 3]
80    a.last
81    a.should == [1, 2, 3]
82    a.last(2)
83    a.should == [1, 2, 3]
84    a.last(3)
85    a.should == [1, 2, 3]
86  end
87end
88