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
|
# truffleruby_primitives: true
require_relative '../../spec_helper'
describe "Kernel#singleton_class" do
it "returns class extended from an object" do
x = Object.new
xs = class << x; self; end
xs.should == x.singleton_class
end
it "returns NilClass for nil" do
nil.singleton_class.should == NilClass
end
it "returns TrueClass for true" do
true.singleton_class.should == TrueClass
end
it "returns FalseClass for false" do
false.singleton_class.should == FalseClass
end
it "raises TypeError for Integer" do
-> { 123.singleton_class }.should raise_error(TypeError, "can't define singleton")
end
it "raises TypeError for Float" do
-> { 3.14.singleton_class }.should raise_error(TypeError, "can't define singleton")
end
it "raises TypeError for Symbol" do
-> { :foo.singleton_class }.should raise_error(TypeError, "can't define singleton")
end
it "raises TypeError for a frozen deduplicated String" do
-> { (-"string").singleton_class }.should raise_error(TypeError, "can't define singleton")
-> { a = -"string"; a.singleton_class }.should raise_error(TypeError, "can't define singleton")
-> { a = "string"; (-a).singleton_class }.should raise_error(TypeError, "can't define singleton")
end
it "returns a frozen singleton class if object is frozen" do
obj = Object.new
obj.freeze
obj.singleton_class.frozen?.should be_true
end
context "for an IO object with a replaced singleton class" do
it "looks up singleton methods from the fresh singleton class after an object instance got a new one" do
proxy = -> io { io.foo }
if RUBY_ENGINE == 'truffleruby'
# We need an inline cache with only this object seen, the best way to do that is to use a Primitive
sclass = -> io { Primitive.singleton_class(io) }
else
sclass = -> io { io.singleton_class }
end
io = File.new(__FILE__)
io.define_singleton_method(:foo) { "old" }
sclass1 = sclass.call(io)
proxy.call(io).should == "old"
# IO#reopen is the only method which can replace an object's singleton class
io2 = File.new(__FILE__)
io.reopen(io2)
io.define_singleton_method(:foo) { "new" }
sclass2 = sclass.call(io)
sclass2.should_not.equal?(sclass1)
proxy.call(io).should == "new"
ensure
io2.close
io.close
end
end
end
|
