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// Copyright (C) 2017 André Bargull. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-runtime-semantics-iteratordestructuringassignmentevaluation
description: >
Ensure correct evaluation order when destructuring target is property reference.
info: |
12.15.5.3 Runtime Semantics: IteratorDestructuringAssignmentEvaluation
AssignmentElement : DestructuringAssignmentTarget Initializer
1. If DestructuringAssignmentTarget is neither an ObjectLiteral nor an ArrayLiteral, then
a. Let lref be the result of evaluating DestructuringAssignmentTarget.
b. ReturnIfAbrupt(lref).
2. If iteratorRecord.[[Done]] is false, then
a. Let next be IteratorStep(iteratorRecord.[[Iterator]]).
...
3. If iteratorRecord.[[Done]] is true, let value be undefined.
...
5. Else, let v be value.
...
8. Return ? PutValue(lref, v).
features: [Symbol.iterator]
includes: [compareArray.js]
---*/
var log = [];
function source() {
log.push("source");
var iterator = {
next: function() {
log.push("iterator-step");
return {
get done() {
log.push("iterator-done");
return true;
},
get value() {
// Note: This getter shouldn't be called.
log.push("iterator-value");
}
};
}
};
var source = {};
source[Symbol.iterator] = function() {
log.push("iterator");
return iterator;
};
return source;
}
function target() {
log.push("target");
return target = {
set q(v) {
log.push("set");
}
};
}
function targetKey() {
log.push("target-key");
return {
toString: function() {
log.push("target-key-tostring");
return "q";
}
};
}
([target()[targetKey()]] = source());
assert.compareArray(log, [
"source", "iterator",
"target", "target-key",
"iterator-step", "iterator-done",
"target-key-tostring", "set",
]);
reportCompare(0, 0);