test262/test/language/expressions/logical-assignment/lgcl-nullish-assignment-ope...

24 lines
685 B
JavaScript

// Copyright (c) 2020 Ecma International. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-assignment-operators-runtime-semantics-evaluation
description: >
Strict Mode - TypeError is not thrown if the LeftHandSide of a Logical
Assignment operator(??=) is a reference to a data property with the
attribute value {[[Writable]]:false} and PutValue step is not reached.
flags: [onlyStrict]
features: [logical-assignment-operators]
---*/
var obj = {};
Object.defineProperty(obj, "prop", {
value: 0,
writable: false,
enumerable: true,
configurable: true
});
assert.sameValue(obj.prop ??= 1, 0, "obj.prop");