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/* Any copyright is dedicated to the Public Domain.
* http://creativecommons.org/licenses/publicdomain/ */
// Reflect.preventExtensions is the same as Object.preventExtensions, except
// for the return value and the behavior in error cases.
var someObjects = [
{},
new Int32Array(7),
Object(Symbol("table")),
new Proxy({}, {})
];
for (var obj of someObjects) {
assertEq(Reflect.preventExtensions(obj), true);
// [[PreventExtensions]] on an already-inextensible object is a no-op.
assertEq(Reflect.preventExtensions(obj), true);
}
// Error cases.
assertThrowsInstanceOf(() => Reflect.isExtensible(), TypeError);
for (var value of [undefined, null, true, 1, NaN, "Phaedo", Symbol("good")]) {
assertThrowsInstanceOf(() => Reflect.isExtensible(value), TypeError);
}
// A proxy's preventExtensions handler can return false without doing anything.
obj = {};
var proxy = new Proxy(obj, {
preventExtensions() { return false; }
});
assertEq(Reflect.preventExtensions(proxy), false);
assertEq(Reflect.isExtensible(obj), true);
assertEq(Reflect.isExtensible(proxy), true);
// If a proxy's preventExtensions handler throws, the exception is propagated.
obj = {};
proxy = new Proxy(obj, {
preventExtensions() { throw "fit"; }
});
assertThrowsValue(() => Reflect.preventExtensions(proxy), "fit");
assertEq(Reflect.isExtensible(obj), true);
assertEq(Reflect.isExtensible(proxy), true);
// If a proxy's preventExtensions handler returns true while leaving the target
// extensible, that's a TypeError.
obj = {};
proxy = new Proxy(obj, {
preventExtensions() { return true; }
});
assertThrowsInstanceOf(() => Reflect.preventExtensions(proxy), TypeError);
assertEq(Reflect.isExtensible(obj), true);
assertEq(Reflect.isExtensible(proxy), true);
// For more Reflect.preventExtensions tests, see target.js.
reportCompare(0, 0);
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