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/*
* The contents of this file are subject to the Netscape Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s): pschwartau@netscape.com
*
*
* The idea behind bug 53268 is as follows. The item 'five' below is defined
* as const, hence is a read-only property of the global object. So if we set
* obj.__proto__ = this, 'five' should become a read-only propery of obj.
*
* If we then change obj.__proto__ to null, obj.five should initially be
* undefined. We should be able to define obj.five to whatever we want,
* and be able to access this value as obj.five.
*
* Bug 53268 was filed because obj.five could not be set or accessed after
* obj.__proto__ had been set to the global object and then to null.
*/
//-----------------------------------------------------------------------------
var bug = '53268';
var status = 'Testing scope after changing obj.__proto__';
var expect= '';
var actual = '';
var obj = {};
const five = 5;
//-----------------------------------------------------------------------------
test();
//-----------------------------------------------------------------------------
function test()
{
enterFunc ("test");
printBugNumber (bug);
printStatus (status);
status= 'Step 1: setting obj.__proto__ = global object';
obj.__proto__ = this;
actual = obj.five;
expect=5;
reportCompare (expect, actual, status);
obj.five=1;
actual = obj.five;
expect=5;
reportCompare (expect, actual, status);
status= 'Step 2: setting obj.__proto__ = null';
obj.__proto__ = null;
actual = obj.five;
expect=undefined;
reportCompare (expect, actual, status);
obj.five=2;
actual = obj.five;
expect=2;
reportCompare (expect, actual, status);
status= 'Step 3: setting obj.__proto__ to global object again';
obj.__proto__ = this;
actual = obj.five;
expect=2; //<--- (FROM STEP 2 ABOVE)
reportCompare (expect, actual, status);
obj.five=3;
actual = obj.five;
expect=3;
reportCompare (expect, actual, status);
status= 'Step 4: setting obj.__proto__ to null again';
obj.__proto__ = null;
actual = obj.five;
expect=3; //<--- (FROM STEP 3 ABOVE)
reportCompare (expect, actual, status);
obj.five=4;
actual = obj.five;
expect=4;
reportCompare (expect, actual, status);
exitFunc ("test");
}
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