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/*
* Any copyright is dedicated to the Public Domain.
* http://creativecommons.org/licenses/publicdomain/
*/
function check(obj, name, value, readonly) {
// Start with a non-configurable, writable data property implemented via
// js::PropertyOp getter and setter.
var pd = Object.getOwnPropertyDescriptor(obj, name);
assertEq(pd.configurable, false, "non-configurable " + name);
assertEq(pd.writable, !readonly, "writable " + name);
try {
// Do not allow a transition from js::PropertyOp to writable js::Value
// data property.
Object.defineProperty(obj, name, {writable: true});
assertEq(0, 1);
} catch (e) {
assertEq('' + e, "TypeError: can't redefine non-configurable property '" + name + "'");
}
if (!readonly) {
try {
// Do not allow the property denoted by name to become a true data
// property via a descriptor that preserves the native property's
// writable attribute.
Object.defineProperty(obj, name, {value: value});
assertEq(0, 1);
} catch (e) {
assertEq('' + e, "TypeError: can't redefine non-configurable property '" + name + "'");
}
}
try {
// Do not allow the property to be frozen at some bogus value.
Object.defineProperty(obj, name, {value: "bogus", writable: false});
assertEq(0, 1);
} catch (e) {
assertEq('' + e, "TypeError: can't redefine non-configurable property '" + name + "'");
}
// Now make name non-writable.
Object.defineProperty(obj, name, {writable: false})
// Assert that the right getter result "stuck".
assertEq(obj[name], value);
// Test that it is operationally non-writable now.
obj[name] = "eek!";
assertEq(obj[name], value);
}
// Reset RegExp.leftContext to the empty string.
/x/.test('x');
var d = Object.getOwnPropertyDescriptor(RegExp, "leftContext");
assertEq(d.set, undefined);
assertEq(typeof d.get, "function");
assertEq(d.enumerable, true);
assertEq(d.configurable, false);
assertEq(d.get.call(RegExp), "");
reportCompare(0, 0, "ok");
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