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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` property after
protocol violation
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
i. Let throw be ? GetMethod(iterator, "throw").
ii. If throw is not undefined, then
[...]
iii. Else,
1. NOTE: If iterator does not have a throw method, this throw is
going to terminate the yield* loop. But first we need to give
iterator a chance to clean up.
2. Perform ? IteratorClose(iterator, Completion{[[Type]]: normal,
[[Value]]: empty, [[Target]]: empty}).
7.4.6 IteratorClose
1. Assert: Type(iterator) is Object.
2. Assert: completion is a Completion Record.
3. 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 caught;
iter.next();
iter.throw();
assert.sameValue(callCount, 1);
assert.sameValue(caught, thrown);
reportCompare(0, 0);