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// |reftest| shell-option(--enable-explicit-resource-management) skip-if(!(this.hasOwnProperty('getBuildConfiguration')&&getBuildConfiguration('explicit-resource-management'))||!xulRuntime.shell) -- explicit-resource-management is not enabled unconditionally, requires shell-options
// Copyright (C) 2023 Ron Buckton. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-let-and-const-declarations-runtime-semantics-evaluation
description: Only reads `[Symbol.dispose]` method once, when initialized.
info: |
RS: Evaluation
UsingDeclaration : using BindingList ;
1. Perform ? BindingEvaluation of BindingList with argument sync-dispose.
2. Return empty.
RS: BindingEvaluation
BindingList : BindingList , LexicalBinding
1. Perform ? BindingEvaluation of BindingList with argument hint.
2. Perform ? BindingEvaluation of LexicalBinding with argument hint.
3. Return unused.
LexicalBinding : BindingIdentifier Initializer
...
5. Return ? InitializeReferencedBinding(lhs, value, hint).
InitializeReferencedBinding ( V, W )
...
4. Return ? base.InitializeBinding(V.[[ReferencedName]], W).
InitializeBinding ( N, V, hint )
...
2. If hint is not normal, perform ? AddDisposableResource(envRec.[[DisposeCapability]], V, hint).
...
AddDisposableResource ( disposeCapability, V, hint [, method ] )
1. If method is not present then,
a. If V is either null or undefined and hint is sync-dispose, then
i. Return unused
b. Let resource be ? CreateDisposableResource(V, hint).
...
CreateDisposableResource ( V, hint [ , method ] )
1. If method is not present, then
a. If V is either null or undefined, then
i. Set V to undefined
ii. Set method to undefined
b. Else,
i. If Type(V) is not Object, throw a TypeError exception.
ii. Set method to ? GetDisposeMethod(V, hint).
iii. If method is undefined, throw a TypeError exception.
2. Else,
a. ...
3. Return the DisposableResource Record { [[ResourceValue]]: V, [[Hint]]: hint, [[DisposeMethod]]: method }.
GetDisposeMethod ( V, hint )
1. If hint is async-dispose, then
a. Let method be ? GetMethod(V, @@asyncDispose).
b. If method is undefined, then
i. Set method to ? GetMethod(V, @@dispose).
2. Else,
a. Let method be ? GetMethod(V, @@dispose).
3. Return method.
features: [explicit-resource-management]
---*/
var resource = {
disposeReadCount: 0,
get [Symbol.dispose]() {
this.disposeReadCount++;
return function() { };
}
};
{
using _ = resource;
}
assert.sameValue(resource.disposeReadCount, 1, 'Expected [Symbol.dispose] to have been read only once');
reportCompare(0, 0);