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// |reftest| skip-if(!this.hasOwnProperty('FinalizationRegistry')) -- FinalizationRegistry is not enabled unconditionally
// Copyright (C) 2019 Leo Balter. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-finalization-registry.prototype.register
description: heldValue may be the same as target
info: |
FinalizationRegistry.prototype.register ( _target_ , _heldValue_ [, _unregisterToken_ ] )
1. Let _finalizationRegistry_ be the *this* value.
2. Perform ? RequireInternalSlot(_finalizationRegistry_, [[Cells]]).
3. If CanBeHeldWeakly(_target_) is *false*, throw a *TypeError* exception.
4. If SameValue(_target_, _heldValue_) is *true*, throw a *TypeError* exception.
features: [FinalizationRegistry, Symbol]
---*/
var finalizationRegistry = new FinalizationRegistry(function() {});
var target = {};
assert.throws(TypeError, () => finalizationRegistry.register(target, target));
// The following will throw regardless of whether the implementation supports
// Symbols as weak values. Step 3 if no, Step 4 if yes.
var symbolTarget = Symbol('a description');
assert.throws(
TypeError,
() => finalizationRegistry.register(symbolTarget, symbolTarget),
'target and heldValue are the same regular symbol'
);
assert.throws(
TypeError,
() => finalizationRegistry.register(Symbol.hasInstance, Symbol.hasInstance),
'target and heldValue are the same well-known symbol'
);
reportCompare(0, 0);
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