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
|
require File.expand_path('../../../spec_helper', __FILE__)
require File.expand_path('../fixtures/classes', __FILE__)
describe "Array#-" do
it "creates an array minus any items from other array" do
([] - [ 1, 2, 4 ]).should == []
([1, 2, 4] - []).should == [1, 2, 4]
([ 1, 2, 3, 4, 5 ] - [ 1, 2, 4 ]).should == [3, 5]
end
it "removes multiple items on the lhs equal to one on the rhs" do
([1, 1, 2, 2, 3, 3, 4, 5] - [1, 2, 4]).should == [3, 3, 5]
end
it "properly handles recursive arrays" do
empty = ArraySpecs.empty_recursive_array
(empty - empty).should == []
([] - ArraySpecs.recursive_array).should == []
array = ArraySpecs.recursive_array
(array - array).should == []
end
it "tries to convert the passed arguments to Arrays using #to_ary" do
obj = mock('[2,3,3,4]')
obj.should_receive(:to_ary).and_return([2, 3, 3, 4])
([1, 1, 2, 2, 3, 4] - obj).should == [1, 1]
end
it "raises a TypeError if the argument cannot be coerced to an Array by calling #to_ary" do
obj = mock('not an array')
lambda { [1, 2, 3] - obj }.should raise_error(TypeError)
end
it "does not return subclass instance for Array subclasses" do
(ArraySpecs::MyArray[1, 2, 3] - []).should be_an_instance_of(Array)
(ArraySpecs::MyArray[1, 2, 3] - ArraySpecs::MyArray[]).should be_an_instance_of(Array)
([1, 2, 3] - ArraySpecs::MyArray[]).should be_an_instance_of(Array)
end
it "does not call to_ary on array subclasses" do
([5, 6, 7] - ArraySpecs::ToAryArray[7]).should == [5, 6]
end
it "removes an item identified as equivalent via #hash and #eql?" do
obj1 = mock('1')
obj2 = mock('2')
obj1.stub!(:hash).and_return(0)
obj2.stub!(:hash).and_return(0)
obj1.should_receive(:eql?).at_least(1).and_return(true)
([obj1] - [obj2]).should == []
([obj1, obj1, obj2, obj2] - [obj2]).should == []
end
it "doesn't remove an item with the same hash but not #eql?" do
obj1 = mock('1')
obj2 = mock('2')
obj1.stub!(:hash).and_return(0)
obj2.stub!(:hash).and_return(0)
obj1.should_receive(:eql?).at_least(1).and_return(false)
([obj1] - [obj2]).should == [obj1]
([obj1, obj1, obj2, obj2] - [obj2]).should == [obj1, obj1]
end
it "removes an identical item even when its #eql? isn't reflexive" do
x = mock('x')
x.stub!(:hash).and_return(42)
x.stub!(:eql?).and_return(false) # Stubbed for clarity and latitude in implementation; not actually sent by MRI.
([x] - [x]).should == []
end
it "is not destructive" do
a = [1, 2, 3]
a - []
a.should == [1, 2, 3]
a - [1]
a.should == [1, 2, 3]
a - [1,2,3]
a.should == [1, 2, 3]
a - [:a, :b, :c]
a.should == [1, 2, 3]
end
end
|
