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// Copyright (C) 2021 Alexey Shvayka. All rights reserved.
// This code is governed by the license found in the LICENSE file.
/*---
esid: sec-object.assign
description: >
[[Set]] to data property of frozen `target` fails with TypeError.
info: |
SetIntegrityLevel ( O, level )
[...]
3. Let status be ? O.[[PreventExtensions]]().
[...]
7. Else,
a. Assert: level is frozen.
b. For each element k of keys, do
i. Let currentDesc be ? O.[[GetOwnProperty]](k).
ii. If currentDesc is not undefined, then
1. If IsAccessorDescriptor(currentDesc) is true, then
[...]
2. Else,
a. Let desc be the PropertyDescriptor { [[Configurable]]: false, [[Writable]]: false }.
3. Perform ? DefinePropertyOrThrow(O, k, desc).
8. Return true.
Object.assign ( target, ...sources )
[...]
3. For each element nextSource of sources, do
a. If nextSource is neither undefined nor null, then
[...]
iii. For each element nextKey of keys, do
1. Let desc be ? from.[[GetOwnProperty]](nextKey).
2. If desc is not undefined and desc.[[Enumerable]] is true, then
[...]
b. Perform ? Set(to, nextKey, propValue, true).
OrdinarySetWithOwnDescriptor ( O, P, V, Receiver, ownDesc )
[...]
3. If IsDataDescriptor(ownDesc) is true, then
a. If ownDesc.[[Writable]] is false, return false.
features: [Symbol, Reflect]
---*/
var sym = Symbol();
var target1 = { [sym]: 1 };
Object.freeze(target1);
assert.throws(TypeError, function() {
Object.assign(target1, { [sym]: 1 });
});
var target2 = Object.freeze({ foo: 1 });
assert.throws(TypeError, function() {
Object.assign(target2, { foo: 1 });
});
reportCompare(0, 0);
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