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// Copyright (C) 2024 André Bargull. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-destructuring-binding-patterns-runtime-semantics-propertybindinginitialization
description: >
Ensure correct evaluation order for binding lookups when destructuring target is var-binding.
info: |
14.3.3.1 Runtime Semantics: PropertyBindingInitialization
BindingProperty : PropertyName : BindingElement
1. Let P be ? Evaluation of PropertyName.
2. Perform ? KeyedBindingInitialization of BindingElement with arguments value, environment, and P.
...
14.3.3.3 Runtime Semantics: KeyedBindingInitialization
SingleNameBinding : BindingIdentifier Initializer_opt
1. Let bindingId be the StringValue of BindingIdentifier.
2. Let lhs be ? ResolveBinding(bindingId, environment).
3. Let v be ? GetV(value, propertyName).
4. If Initializer is present and v is undefined, then
...
b. Else,
i. Let defaultValue be ? Evaluation of Initializer.
ii. Set v to ? GetValue(defaultValue).
...
6. Return ? InitializeReferencedBinding(lhs, v).
9.4.2 ResolveBinding ( name [ , env ] )
...
4. Return ? GetIdentifierReference(env, name, strict).
9.1.2.1 GetIdentifierReference ( env, name, strict )
...
2. Let exists be ? env.HasBinding(name).
...
includes: [compareArray.js]
features: [Proxy]
flags: [noStrict]
---*/
var log = [];
var sourceKey = {
toString: () => {
log.push("sourceKey");
return "p";
}
};
var source = {
get p() {
log.push("get source");
return undefined;
}
};
var env = new Proxy({}, {
has(t, pk) {
log.push("binding::" + pk);
return false;
}
});
var defaultValue = 0;
var varTarget;
with (env) {
var {
[sourceKey]: varTarget = defaultValue
} = source;
}
assert.compareArray(log, [
"binding::source",
"binding::sourceKey",
"sourceKey",
"binding::varTarget",
"get source",
"binding::defaultValue",
]);
reportCompare(0, 0);