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// This file was procedurally generated from the following sources:
// - src/dstr-assignment/array-elem-iter-rtrn-close-null.case
// - src/dstr-assignment/default/for-of.template
/*---
description: IteratorClose throws a TypeError when `return` returns a non-Object value (For..of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [Symbol.iterator, generators, destructuring-binding]
flags: [generated]
info: |
IterationStatement :
for ( LeftHandSideExpression of AssignmentExpression ) Statement
1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« »,
AssignmentExpression, iterate).
2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement,
keyResult, assignment, labelSet).
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
[...]
4. If destructuring is true and if lhsKind is assignment, then
a. Assert: lhs is a LeftHandSideExpression.
b. Let assignmentPattern be the parse of the source text corresponding to
lhs using AssignmentPattern as the goal symbol.
[...]
ArrayAssignmentPattern : [ AssignmentElementList ]
[...]
5. If iteratorRecord.[[done]] is false, return IteratorClose(iterator,
result).
6. Return result.
7.4.6 IteratorClose( iterator, completion )
[...]
6. Let innerResult be Call(return, iterator, « »).
7. If completion.[[type]] is throw, return Completion(completion).
8. If innerResult.[[type]] is throw, return Completion(innerResult).
9. If Type(innerResult.[[value]]) is not Object, throw a TypeError
exception.
---*/
var nextCount = 0;
var returnCount = 0;
var unreachable = 0;
var iterator = {
next: function() {
nextCount += 1;
return {done: false, value: undefined};
},
return: function() {
returnCount += 1;
return null;
}
};
var iterable = {};
iterable[Symbol.iterator] = function() {
return iterator;
};
function* g() {
var counter = 0;
for ([ {} = yield ] of [iterable]) {
unreachable += 1;
counter += 1;
}
assert.sameValue(counter, 1);
}
var iter = g();
iter.next();
assert.sameValue(nextCount, 1);
assert.sameValue(returnCount, 0);
assert.throws(TypeError, function() {
iter.return();
});
assert.sameValue(nextCount, 1);
assert.sameValue(returnCount, 1);
assert.sameValue(unreachable, 0, 'Unreachable statement was not executed');
reportCompare(0, 0);
|
