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// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-generator-function-definitions-runtime-semantics-evaluation
description: >
If iterator's "throw" method is `null`,
IteratorClose is called before rising TypeError.
info: |
YieldExpression : yield * AssignmentExpression
[...]
7. Repeat,
[...]
b. Else if received.[[Type]] is throw, then
i. Let throw be ? GetMethod(iterator, "throw").
ii. If throw is not undefined, then
[...]
iii. Else,
[...]
4. Else, perform ? IteratorClose(iteratorRecord, closeCompletion).
[...]
6. Throw a TypeError exception.
GetMethod ( V, P )
[...]
2. Let func be ? GetV(V, P).
3. If func is either undefined or null, return undefined.
IteratorClose ( iteratorRecord, completion )
[...]
4. Let innerResult be GetMethod(iterator, "return").
5. If innerResult.[[Type]] is normal, then
a. Let return be innerResult.[[Value]].
b. If return is undefined, return Completion(completion).
features: [generators, Symbol.iterator]
---*/
var throwGets = 0;
var returnGets = 0;
var iterable = {
next: function() {
return {value: 1, done: false};
},
get throw() {
throwGets += 1;
return null;
},
get return() {
returnGets += 1;
},
};
iterable[Symbol.iterator] = function() {
return iterable;
};
function* generator() {
yield* iterable;
}
var iterator = generator();
iterator.next();
assert.throws(TypeError, function() {
iterator.throw();
});
assert.sameValue(throwGets, 1);
assert.sameValue(returnGets, 1);
reportCompare(0, 0);