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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-generator-function-definitions-runtime-semantics-evaluation
es6id: 14.4.14
description: Abrupt completion returned when accessing iterator `return` method
info: |
YieldExpression : yield * AssignmentExpression
1. Let exprRef be the result of evaluating AssignmentExpression.
2. Let value be ? GetValue(exprRef).
3. Let iterator be ? GetIterator(value).
4. Let received be NormalCompletion(undefined).
5. Repeat
a. If received.[[Type]] is normal, then
[...]
b. Else if received.[[Type]] is throw, then
[...]
c. Else,
i. Assert: received.[[Type]] is return.
ii. Let return be ? GetMethod(iterator, "return").
features: [generators, Symbol.iterator]
---*/
var thrown = new Test262Error();
var badIter = {};
var callCount = 0;
var poisonedReturn = {
next: function() {
return { done: false };
}
};
Object.defineProperty(poisonedReturn, 'throw', {
get: function() {
callCount += 1;
}
});
Object.defineProperty(poisonedReturn, 'return', {
get: function() {
throw thrown;
}
});
badIter[Symbol.iterator] = function() {
return poisonedReturn;
};
function* g() {
try {
yield * badIter;
} catch (err) {
caught = err;
}
}
var iter = g();
var result, caught;
iter.next();
assert.sameValue(caught, undefined, '`return` property not accessed eagerly');
result = iter.return();
assert.sameValue(result.value, undefined);
assert.sameValue(result.done, true);
assert.sameValue(caught, thrown);
assert.sameValue(callCount, 0, 'iterator `throw` property is not accessed');
reportCompare(0, 0);
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