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// |reftest| shell-option(--enable-symbols-as-weakmap-keys) skip-if(release_or_beta||!xulRuntime.shell) -- symbols-as-weakmap-keys is not released yet, requires shell-options
// Copyright (C) 2022 Igalia, S.L. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-weakmap.prototype.get
description: >
Returns undefined when a Symbol key is not on the WeakMap object.
info: |
WeakMap.prototype.get ( _key_ )
3. Let _entries_ be the List that is _M_.[[WeakMapData]].
4. If CanBeHeldWeakly(_key_) is *false*, return *undefined*.
5. For each Record {[[Key]], [[Value]]} _p_ of _entries_, do
a. If _p_.[[Key]] is not empty and SameValue(_p_.[[Key]], _key_) is *true*,
return _p_.[[Value]].
6. Return *undefined*.
features: [Symbol, WeakMap, symbols-as-weakmap-keys]
---*/
var map = new WeakMap();
var key = Symbol('a description');
assert.sameValue(map.get(key), undefined, 'returns undefined for regular symbol on initially empty map');
assert.sameValue(
map.get(Symbol.hasInstance),
undefined,
'returns undefined for well-known symbol on initially empty map'
);
map.set(key, 1);
map.set(Symbol.hasInstance, 2);
map.delete(key);
map.delete(Symbol.hasInstance);
assert.sameValue(map.get(key), undefined, 'returns undefined for deleted regular symbol');
assert.sameValue(map.get(Symbol.hasInstance), undefined, 'returns undefined for deleted well-known symbol');
reportCompare(0, 0);
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