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23
24description("Test to ensure correct behaviour of Object.defineProperty");
25
26shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {value:1}), 'foo'))",
27         "JSON.stringify({value: 1, writable: false, enumerable: false, configurable: false})");
28shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {}), 'foo'))",
29         "JSON.stringify({writable: false, enumerable: false, configurable: false})");
30shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {get:undefined}), 'foo'))",
31         "JSON.stringify({enumerable: false, configurable: false})");
32shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {value:1, writable: false}), 'foo'))",
33         "JSON.stringify({value: 1, writable: false, enumerable: false, configurable: false})");
34shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {value:1, writable: true}), 'foo'))",
35         "JSON.stringify({value: 1, writable: true, enumerable: false, configurable: false})");
36shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {value:1, enumerable: false}), 'foo'))",
37         "JSON.stringify({value: 1, writable: false, enumerable: false, configurable: false})");
38shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {value:1, enumerable: true}), 'foo'))",
39         "JSON.stringify({value: 1, writable: false, enumerable: true, configurable: false})");
40shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {value:1, configurable: false}), 'foo'))",
41         "JSON.stringify({value: 1, writable: false, enumerable: false, configurable: false})");
42shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty({}, 'foo', {value:1, configurable: true}), 'foo'))",
43         "JSON.stringify({value: 1, writable: false, enumerable: false, configurable: true})");
44shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty([1,2,3], 'foo', {value:1, configurable: true}), 'foo'))",
45         "JSON.stringify({value: 1, writable: false, enumerable: false, configurable: true})");
46shouldBe("Object.getOwnPropertyDescriptor(Object.defineProperty([1,2,3], '1', {value:'foo', configurable: true}), '1').value", "'foo'");
47shouldBe("a=[1,2,3], Object.defineProperty(a, '1', {value:'foo', configurable: true}), a[1]", "'foo'");
48shouldBe("Object.getOwnPropertyDescriptor(Object.defineProperty([1,2,3], '1', {get:getter, configurable: true}), '1').get", "getter");
49shouldThrow("Object.defineProperty([1,2,3], '1', {get:getter, configurable: true})[1]", "'called getter'");
50
51shouldThrow("Object.defineProperty()");
52shouldThrow("Object.defineProperty(null)");
53shouldThrow("Object.defineProperty('foo')");
54shouldThrow("Object.defineProperty({})");
55shouldThrow("Object.defineProperty({}, 'foo')");
56shouldThrow("Object.defineProperty({}, 'foo', {get:undefined, value:true}).foo");
57shouldBeTrue("Object.defineProperty({get foo() { return true; } }, 'foo', {configurable:false}).foo");
58
59function createUnconfigurableProperty(o, prop, writable, enumerable) {
60    writable = writable || false;
61    enumerable = enumerable || false;
62    return Object.defineProperty(o, prop, {value:1, configurable:false, writable: writable, enumerable: enumerable});
63}
64shouldThrow("Object.defineProperty(createUnconfigurableProperty({}, 'foo'), 'foo', {configurable: true})");
65shouldThrow("Object.defineProperty(createUnconfigurableProperty({}, 'foo'), 'foo', {writable: true})");
66shouldThrow("Object.defineProperty(createUnconfigurableProperty({}, 'foo'), 'foo', {enumerable: true})");
67shouldThrow("Object.defineProperty(createUnconfigurableProperty({}, 'foo', false, true), 'foo', {enumerable: false}), 'foo'");
68
69shouldBe("JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty(createUnconfigurableProperty({}, 'foo', true), 'foo', {writable: false}), 'foo'))",
70         "JSON.stringify({value: 1, writable: false, enumerable: false, configurable: false})");
71
72shouldThrow("Object.defineProperty({}, 'foo', {value:1, get: function(){}})");
73shouldThrow("Object.defineProperty({}, 'foo', {value:1, set: function(){}})");
74shouldThrow("Object.defineProperty({}, 'foo', {writable:true, get: function(){}})");
75shouldThrow("Object.defineProperty({}, 'foo', {writable:true, set: function(){}})");
76shouldThrow("Object.defineProperty({}, 'foo', {get: null})");
77shouldThrow("Object.defineProperty({}, 'foo', {set: null})");
78function getter(){ throw "called getter"; }
79function getter1(){ throw "called getter1"; }
80function setter(){ throw "called setter"; }
81function setter1(){ throw "called setter1"; }
82shouldThrow("Object.defineProperty({}, 'foo', {set: setter}).foo='test'", "'called setter'");
83shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter}), 'foo', {set: setter1})");
84shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter}), 'foo', {get: getter1})");
85shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter}), 'foo', {value: 1})");
86shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {set: setter1}).foo='test'", "'called setter1'");
87shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {get: getter1}).foo", "'called getter1'");
88shouldBeTrue("Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {value: true}).foo");
89shouldBeTrue("'foo' in Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {writable: true})");
90shouldBeUndefined("Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {writable: true}).foo");
91shouldThrow("Object.defineProperty({}, 'foo', {get: getter}).foo", "'called getter'");
92shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {get: getter}), 'foo', {get: getter1})");
93shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {get: getter}), 'foo', {set: setter1})");
94shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {get: getter, configurable: true}), 'foo', {get: getter1}).foo", "'called getter1'");
95shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {get: getter, configurable: true}), 'foo', {set: setter1}).foo='test'", "'called setter1'");
96shouldBeTrue("Object.defineProperty(Object.defineProperty({}, 'foo', {get: getter, configurable: true}), 'foo', {value: true}).foo");
97shouldBeUndefined("Object.defineProperty(Object.defineProperty({}, 'foo', {get: getter, configurable: true}), 'foo', {writable: true}).foo");
98shouldBeTrue("'foo' in Object.defineProperty(Object.defineProperty({}, 'foo', {get: getter, configurable: true}), 'foo', {writable: true})");
99
100shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1}), 'foo', {set: setter1})");
101shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1, configurable: true}), 'foo', {set: setter1}).foo='test'", "'called setter1'");
102shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1}), 'foo', {get: getter1})");
103shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1}), 'foo', {set: setter1})");
104shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1, configurable: true}), 'foo', {get: getter1}).foo", "'called getter1'");
105shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1, configurable: true}), 'foo', {set: setter1}).foo='test'", "'called setter1'");
106
107// Should be able to redefine an non-writable property, if it is configurable.
108shouldBe("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1, configurable: true, writable: false}), 'foo', {value: 2, configurable: true, writable: true}).foo", "2");
109shouldBe("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1, configurable: true, writable: false}), 'foo', {value: 2, configurable: true, writable: false}).foo", "2");
110
111// Should be able to redefine an non-writable, non-configurable property, with the same value and attributes.
112shouldBe("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1, configurable: false, writable: false}), 'foo', {value: 1, configurable: false, writable: false}).foo", "1");
113
114// Should be able to redefine a configurable accessor, with the same or with different attributes.
115// Check the accessor function changed.
116shouldBe("Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: true, enumerable: true}), 'foo', {get: function() { return 2; }, configurable: true, enumerable: false}).foo", "2");
117shouldBe("Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: true, enumerable: false}), 'foo', {get: function() { return 2; }, configurable: true, enumerable: false}).foo", "2");
118// Check the attributes changed.
119shouldBeFalse("var result = false; var o = Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: true, enumerable: true}), 'foo', {get: function() { return 2; }, configurable: true, enumerable: false}); for (x in o) result = true; result");
120shouldBeTrue("var result = false; var o = Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: true, enumerable: false}), 'foo', {get: function() { return 2; }, configurable: true, enumerable: true}); for (x in o) result = true; result");
121
122// Should be able to define an non-configurable accessor.
123shouldBeUndefined("var o = Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: true}); delete o.foo; o.foo");
124shouldBe("var o = Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: false}); delete o.foo; o.foo", '1');
125shouldBe("Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: true}), 'foo', {value:2}).foo", "2");
126shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: false}), 'foo', {value:2}).foo");
127
128// Defining a data descriptor over an accessor should result in a read only property.
129shouldBe("var o = Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return 1; }, configurable: true}), 'foo', {value:2}); o.foo = 3; o.foo", "2");
130
131// Trying to redefine a non-configurable property as configurable should throw.
132shouldThrow("Object.defineProperty(Object.defineProperty({}, 'foo', {value: 1}), 'foo', {value:2, configurable: true})");
133shouldThrow("Object.defineProperty(Object.defineProperty([], 'foo', {value: 1}), 'foo', {value:2, configurable: true})");
134
135// Test an object with a getter setter.
136// Either accessor may be omitted or replaced with undefined, or both may be replaced with undefined.
137shouldBe("var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}); o.foo", '42')
138shouldBe("var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}); o.foo = 42; o.result;", '42');
139shouldBe("var o = Object.defineProperty({}, 'foo', {get:undefined, set:function(x){this.result = x;}}); o.foo", 'undefined')
140shouldBe("var o = Object.defineProperty({}, 'foo', {get:undefined, set:function(x){this.result = x;}}); o.foo = 42; o.result;", '42');
141shouldBe("var o = Object.defineProperty({}, 'foo', {set:function(x){this.result = x;}}); o.foo", 'undefined')
142shouldBe("var o = Object.defineProperty({}, 'foo', {set:function(x){this.result = x;}}); o.foo = 42; o.result;", '42');
143shouldBe("var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}, set:undefined}); o.foo", '42')
144shouldBe("var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}, set:undefined}); o.foo = 42; o.result;", 'undefined');
145shouldBe("var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}}); o.foo", '42')
146shouldBe("var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}}); o.foo = 42; o.result;", 'undefined');
147shouldBe("var o = Object.defineProperty({}, 'foo', {get:undefined, set:undefined}); o.foo", 'undefined')
148shouldBe("var o = Object.defineProperty({}, 'foo', {get:undefined, set:undefined}); o.foo = 42; o.result;", 'undefined');
149// Test replacing or removing either the getter or setter individually.
150shouldBe("var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {get:function(){return 13;}}); o.foo", '13')
151shouldBe("var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {get:function(){return 13;}}); o.foo = 42; o.result;", '42')
152shouldBe("var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {get:undefined}); o.foo", 'undefined')
153shouldBe("var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {get:undefined}); o.foo = 42; o.result;", '42')
154shouldBe("var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {set:function(){this.result = 13;}}); o.foo", '42')
155shouldBe("var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {set:function(){this.result = 13;}}); o.foo = 42; o.result;", '13')
156shouldBe("var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {set:undefined}); o.foo", '42')
157shouldBe("var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {set:undefined}); o.foo = 42; o.result;", 'undefined')
158
159// Repeat of the above, in strict mode.
160// Either accessor may be omitted or replaced with undefined, or both may be replaced with undefined.
161shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}); o.foo", '42')
162shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}); o.foo = 42; o.result;", '42');
163shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {get:undefined, set:function(x){this.result = x;}}); o.foo", 'undefined')
164shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {get:undefined, set:function(x){this.result = x;}}); o.foo = 42; o.result;", '42');
165shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {set:function(x){this.result = x;}}); o.foo", 'undefined')
166shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {set:function(x){this.result = x;}}); o.foo = 42; o.result;", '42');
167shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}, set:undefined}); o.foo", '42')
168shouldThrow("'use strict'; var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}, set:undefined}); o.foo = 42; o.result;");
169shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}}); o.foo", '42')
170shouldThrow("'use strict'; var o = Object.defineProperty({}, 'foo', {get:function(){return 42;}}); o.foo = 42; o.result;");
171shouldBe("'use strict'; var o = Object.defineProperty({}, 'foo', {get:undefined, set:undefined}); o.foo", 'undefined')
172shouldThrow("'use strict'; var o = Object.defineProperty({}, 'foo', {get:undefined, set:undefined}); o.foo = 42; o.result;");
173// Test replacing or removing either the getter or setter individually.
174shouldBe("'use strict'; var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {get:function(){return 13;}}); o.foo", '13')
175shouldBe("'use strict'; var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {get:function(){return 13;}}); o.foo = 42; o.result;", '42')
176shouldBe("'use strict'; var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {get:undefined}); o.foo", 'undefined')
177shouldBe("'use strict'; var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {get:undefined}); o.foo = 42; o.result;", '42')
178shouldBe("'use strict'; var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {set:function(){this.result = 13;}}); o.foo", '42')
179shouldBe("'use strict'; var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {set:function(){this.result = 13;}}); o.foo = 42; o.result;", '13')
180shouldBe("'use strict'; var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {set:undefined}); o.foo", '42')
181shouldThrow("'use strict'; var o = Object.defineProperty(Object.defineProperty({foo:1}, 'foo', {get:function(){return 42;}, set:function(x){this.result = x;}}), 'foo', {set:undefined}); o.foo = 42; o.result;")
182
183Object.defineProperty(Object.prototype, 0, {get:function(){ return false; }, configurable:true})
184shouldBeTrue("0 in Object.prototype");
185shouldBeTrue("'0' in Object.prototype");
186delete Object.prototype[0];
187
188Object.defineProperty(Object.prototype, 'readOnly', {value:true, configurable:true, writable:false})
189shouldBeTrue("var o = {}; o.readOnly = false; o.readOnly");
190shouldThrow("'use strict'; var o = {}; o.readOnly = false; o.readOnly");
191delete Object.prototype.readOnly;
192
193// Check the writable attribute is set correctly when redefining an accessor as a data descriptor.
194shouldBeFalse("Object.getOwnPropertyDescriptor(Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return false; }, configurable: true}), 'foo', {value:false}), 'foo').writable");
195shouldBeFalse("Object.getOwnPropertyDescriptor(Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return false; }, configurable: true}), 'foo', {value:false, writable: false}), 'foo').writable");
196shouldBeTrue("Object.getOwnPropertyDescriptor(Object.defineProperty(Object.defineProperty({}, 'foo', {get: function() { return false; }, configurable: true}), 'foo', {value:false, writable: true}), 'foo').writable");
197
198// If array length is read-only, [[Put]] should fail.
199shouldBeFalse("var a = Object.defineProperty([], 'length', {writable: false}); a[0] = 42; 0 in a;");
200shouldThrow("'use strict'; var a = Object.defineProperty([], 'length', {writable: false}); a[0] = 42; 0 in a;");
201
202// If array property is read-only, [[Put]] should fail.
203shouldBe("var a = Object.defineProperty([42], '0', {writable: false}); a[0] = false; a[0];", '42');
204shouldThrow("'use strict'; var a = Object.defineProperty([42], '0', {writable: false}); a[0] = false; a[0];");
205
206// If array property is an undefined setter, [[Put]] should fail.
207shouldBeUndefined("var a = Object.defineProperty([], '0', {set: undefined}); a[0] = 42; a[0];");
208shouldThrow("'use strict'; var a = Object.defineProperty([], '0', {set: undefined}); a[0] = 42; a[0];");
209
210function testObject()
211{
212    // Test case from https://bugs.webkit.org/show_bug.cgi?id=38636
213    Object.defineProperty(anObj, 'slot1', {value: 'foo', enumerable: true});
214    Object.defineProperty(anObj, 'slot2', {value: 'bar', writable: true});
215    Object.defineProperty(anObj, 'slot3', {value: 'baz', enumerable: false});
216    Object.defineProperty(anObj, 'slot4', {value: 'goo', configurable: false});
217    shouldBe("anObj.slot1", '"foo"');
218    shouldBe("anObj.slot2", '"bar"');
219    anObj.slot2 = 'bad value';
220    shouldBeTrue("anObj.propertyIsEnumerable('slot1')");
221    shouldBeFalse("anObj.propertyIsEnumerable('slot2')");
222    delete anObj.slot4;
223    shouldBe("anObj.slot4", '"goo"');
224
225    // Test case from https://bugs.webkit.org/show_bug.cgi?id=48911
226    Object.defineProperty(Object.getPrototypeOf(anObj), 'slot5', {get: function() { return this._Slot5; }, set: function(v) { this._Slot5 = v; }, configurable: false});
227    anObj.slot5 = 123;
228    shouldBe("anObj.slot5", '123');
229    shouldBe("anObj._Slot5", '123');
230    shouldBeUndefined("Object.getOwnPropertyDescriptor(anObj, 'slot5')");
231    Object.defineProperty(anObj, 'slot5', { value: 456 });
232    shouldBe("anObj.slot5", '456');
233    shouldBe("anObj._Slot5", '123');
234    shouldBe("Object.getOwnPropertyDescriptor(anObj, 'slot5').value", '456');
235}
236var anObj = {};
237testObject();
238var anObj = this;
239testObject();
240