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// |reftest| shell-option(--enable-upsert) skip-if(!WeakMap.prototype.getOrInsertComputed)
// Copyright (C) 2015 the V8 project authors. 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: Throws TypeError if key cannot be held weakly.
info: |
WeakMap.prototype.getOrInsertComputed ( key, callbackfn )
...
4. If CanBeHeldWeakly(_key_) is *false*, throw a *TypeError* exception.
...
features: [Symbol, WeakMap]
---*/
var s = new WeakMap();
assertThrowsInstanceOf(function() {
s.getOrInsertComputed(1, () => 1);
}, TypeError);
assertThrowsInstanceOf(function() {
s.getOrInsertComputed(false, () => 1);
}, TypeError);
assertThrowsInstanceOf(function() {
s.getOrInsertComputed(undefined, () => 1);
}, TypeError);
assertThrowsInstanceOf(function() {
s.getOrInsertComputed('string', () => 1);
}, TypeError);
assertThrowsInstanceOf(function() {
s.getOrInsertComputed(null, () => 1);
}, TypeError);
assertThrowsInstanceOf(function() {
s.getOrInsertComputed(Symbol.for('registered symbol'), () => 1);
}, TypeError, 'Registered symbol not allowed as WeakMap key');
reportCompare(0, 0);