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
|
/// Copyright (c) 2009 Microsoft Corporation
///
/// Redistribution and use in source and binary forms, with or without modification, are permitted provided
/// that the following conditions are met:
/// * Redistributions of source code must retain the above copyright notice, this list of conditions and
/// the following disclaimer.
/// * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and
/// the following disclaimer in the documentation and/or other materials provided with the distribution.
/// * Neither the name of Microsoft nor the names of its contributors may be used to
/// endorse or promote products derived from this software without specific prior written permission.
///
/// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
/// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
/// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
/// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
/// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
/// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
/// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
/// ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
/**
* Step 4 of defineProperty calls the [[DefineOwnProperty]] internal method
* of O to define the property. Step 6 of [[DefineOwnProperty]] returns if
* every field of desc also occurs in current and every field in desc has
* the same value as current.
*
* @path ch15/15.2/15.2.3/15.2.3.6/15.2.3.6-4-6.js
* @description Object.defineProperty is no-op if current and desc are the same accessor desc
*/
function testcase() {
function sameAccessorDescriptorValues(d1, d2) {
return (d1.get == d2.get &&
d1.enumerable == d2.enumerable &&
d1.configurable == d2.configurable);
}
var o = {};
// create an accessor property with the following attributes:
// enumerable: true, configurable: true
var desc = {
get: function () {},
enumerable: true,
configurable: true
};
Object.defineProperty(o, "foo", desc);
// query for, and save, the desc. A subsequent call to defineProperty
// with the same desc should not disturb the property definition.
var d1 = Object.getOwnPropertyDescriptor(o, "foo");
// now, redefine the property with the same descriptor
// the property defintion should not get disturbed.
Object.defineProperty(o, "foo", desc);
var d2 = Object.getOwnPropertyDescriptor(o, "foo");
if (sameAccessorDescriptorValues(d1, d2) === true) {
return true;
}
}
runTestCase(testcase);
|
