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// |reftest| shell-option(--enable-upsert) skip-if(!WeakMap.prototype.getOrInsert)
// Copyright (C) 2020 Rick Waldron. All rights reserved.
// Copyright (C) 2025 Jonas Haukenes. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: proposal-upsert
description: >
WeakMap.prototype.getOrInsert does not implement [[Construct]], is not new-able
info: |
ECMAScript Function Objects
Built-in function objects that are not identified as constructors do not
implement the [[Construct]] internal method unless otherwise specified in
the description of a particular function.
sec-evaluatenew
...
7. If IsConstructor(constructor) is false, throw a TypeError exception.
...
includes: [isConstructor.js]
features: [Reflect.construct, WeakMap, arrow-function]
---*/
assertEq(
isConstructor(WeakMap.prototype.getOrInsert),
false,
'isConstructor(WeakMap.prototype.getOrInsert) must return false'
);
assertThrowsInstanceOf(() => {
let wm = new WeakMap(); new wm.getOrInsert({}, 1);
}, TypeError);
reportCompare(0, 0);