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'use strict';
// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-array.from
description: >
`this` value of mapping function in strict mode (traversed via iterator)
info: |
[...]
2. If mapfn is undefined, let mapping be false.
3. else
a. If IsCallable(mapfn) is false, throw a TypeError exception.
b. If thisArg was supplied, let T be thisArg; else let T be undefined.
c. Let mapping be true
[...]
6. If usingIterator is not undefined, then
[...]
g. Repeat
[...]
vii. If mapping is true, then
1. Let mappedValue be Call(mapfn, T, «nextValue, k»).
features: [Symbol.iterator]
flags: [onlyStrict]
---*/
var thisVals = [];
var nextResult = {
done: false,
value: {}
};
var nextNextResult = {
done: false,
value: {}
};
var mapFn = function() {
thisVals.push(this);
};
var items = {};
items[Symbol.iterator] = function() {
return {
next: function() {
var result = nextResult;
nextResult = nextNextResult;
nextNextResult = {
done: true
};
return result;
}
};
};
Array.from(items, mapFn);
assert.sameValue(thisVals.length, 2, 'The value of thisVals.length is expected to be 2');
assert.sameValue(thisVals[0], undefined, 'The value of thisVals[0] is expected to equal undefined');
assert.sameValue(thisVals[1], undefined, 'The value of thisVals[1] is expected to equal undefined');
reportCompare(0, 0);