test262/test/language/expressions/yield/star-rhs-iter-rtrn-res-valu...

71 lines
1.9 KiB
JavaScript

// 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 `value` property of iteration
result
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").
iii. If return is undefined, return Completion(received).
iv. Let innerReturnResult be ? Call(return, iterator, «
received.[[Value]] »).
v. If Type(innerReturnResult) is not Object, throw a TypeError
exception.
vi. Let done be ? IteratorComplete(innerReturnResult).
vii. If done is true, then
1. Let value be ? IteratorValue(innerReturnResult).
7.4.4 IteratorValue
1. Assert: Type(iterResult) is Object.
2. Return ? Get(iterResult, "value").
features: [generators, Symbol.iterator]
---*/
var thrown = new Test262Error();
var badIter = {};
var poisonedValue = Object.defineProperty({ done: true }, 'value', {
get: function() {
throw thrown;
}
});
badIter[Symbol.iterator] = function() {
return {
next: function() {
return { done: false };
},
return: function() {
return poisonedValue;
}
};
};
function* g() {
try {
yield * badIter;
} catch (err) {
caught = err;
}
}
var iter = g();
var caught;
iter.next();
iter.return();
assert.sameValue(caught, thrown);