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
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
|
/* Any copyright is dedicated to the Public Domain.
* http://creativecommons.org/licenses/publicdomain/ */
// Basic tests for standard Object APIs interacting with symbols.
// Object.defineProperty
function F() {}
var f = new F;
Object.defineProperty(f, Symbol.for("name"), {
configurable: true,
value: "eff"
});
assertEq("name" in f, false);
assertEq("Symbol(name)" in f, false);
assertEq(Symbol.for("name") in f, true);
assertEq(f[Symbol.for("name")], "eff");
// Object.defineProperties
function D() {}
var descs = new D;
var s1 = Symbol("s1");
var hits = 0;
descs[s1] = {
get: () => hits++,
set: undefined,
enumerable: true,
configurable: true
};
var s2 = Symbol("s2");
descs[s2] = {
value: {},
writable: true,
enumerable: false,
configurable: true
};
var s3 = Symbol("s3");
D.prototype[s3] = {value: "FAIL"};
assertEq(Object.defineProperties(f, descs), f);
assertEq(s1 in f, true);
assertEq(f[s1], 0);
assertEq(hits, 1);
assertEq(s2 in f, true);
assertEq(f[s2], descs[s2].value);
assertEq(s3 in f, false);
// Object.create
var n = Object.create({}, descs);
assertEq(s1 in n, true);
assertEq(n[s1], 1);
assertEq(hits, 2);
assertEq(s2 in n, true);
assertEq(n[s2], descs[s2].value);
assertEq(s3 in n, false);
// Object.getOwnPropertyDescriptor
var desc = Object.getOwnPropertyDescriptor(n, s1);
assertDeepEq(desc, descs[s1]);
assertEq(desc.get, descs[s1].get);
desc = Object.getOwnPropertyDescriptor(n, s2);
assertDeepEq(desc, descs[s2]);
assertEq(desc.value, descs[s2].value);
// Object.prototype.hasOwnProperty
assertEq(descs.hasOwnProperty(s1), true);
assertEq(descs.hasOwnProperty(s2), true);
assertEq(descs.hasOwnProperty(s3), false);
assertEq([].hasOwnProperty(Symbol.iterator), false);
assertEq(Array.prototype.hasOwnProperty(Symbol.iterator), true);
// Object.prototype.propertyIsEnumerable
assertEq(n.propertyIsEnumerable(s1), true);
assertEq(n.propertyIsEnumerable(s2), false);
assertEq(n.propertyIsEnumerable(s3), false); // no such property
assertEq(D.prototype.propertyIsEnumerable(s3), true);
assertEq(descs.propertyIsEnumerable(s3), false); // inherited properties are not considered
// Object.preventExtensions
var obj = {};
obj[s1] = 1;
assertEq(Object.preventExtensions(obj), obj);
assertThrowsInstanceOf(function () { "use strict"; obj[s2] = 2; }, TypeError);
obj[s2] = 2; // still no effect
assertEq(s2 in obj, false);
// Object.isSealed, Object.isFrozen
assertEq(Object.isSealed(obj), false);
assertEq(Object.isFrozen(obj), false);
assertEq(delete obj[s1], true);
assertEq(Object.isSealed(obj), true);
assertEq(Object.isFrozen(obj), true);
obj = {};
obj[s1] = 1;
Object.preventExtensions(obj);
Object.defineProperty(obj, s1, {configurable: false}); // still writable
assertEq(Object.isSealed(obj), true);
assertEq(Object.isFrozen(obj), false);
obj[s1] = 2;
assertEq(obj[s1], 2);
Object.defineProperty(obj, s1, {writable: false});
assertEq(Object.isFrozen(obj), true);
// Object.seal, Object.freeze
var obj = {};
obj[s1] = 1;
Object.seal(obj);
desc = Object.getOwnPropertyDescriptor(obj, s1);
assertEq(desc.configurable, false);
assertEq(desc.writable, true);
Object.freeze(obj);
assertEq(Object.getOwnPropertyDescriptor(obj, s1).writable, false);
// Object.setPrototypeOf purges caches for symbol-keyed properties.
var proto = {};
proto[s1] = 1;
Object.defineProperty(proto, s2, {
get: () => 2,
set: v => undefined
});
var obj = Object.create(proto);
var last1, last2;
var N = 9;
for (var i = 0; i < N; i++) {
last1 = obj[s1];
last2 = obj[s2];
obj[s2] = "marker";
if (i === N - 2)
Object.setPrototypeOf(obj, {});
}
assertEq(last1, undefined);
assertEq(last2, undefined);
assertEq(obj.hasOwnProperty(s2), true);
assertEq(obj[s2], "marker");
if (typeof reportCompare === "function")
reportCompare(0, 0);
|