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// 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: Value returned by mapping function (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»).
2. If mappedValue is an abrupt completion, return
IteratorClose(iterator, mappedValue).
3. Let mappedValue be mappedValue.[[value]].
features: [Symbol.iterator]
---*/
var thisVals = [];
var nextResult = {
done: false,
value: {}
};
var nextNextResult = {
done: false,
value: {}
};
var firstReturnVal = {};
var secondReturnVal = {};
var mapFn = function(value, idx) {
var returnVal = nextReturnVal;
nextReturnVal = nextNextReturnVal;
nextNextReturnVal = null;
return returnVal;
};
var nextReturnVal = firstReturnVal;
var nextNextReturnVal = secondReturnVal;
var items = {};
var result;
items[Symbol.iterator] = function() {
return {
next: function() {
var result = nextResult;
nextResult = nextNextResult;
nextNextResult = {
done: true
};
return result;
}
};
};
result = Array.from(items, mapFn);
assert.sameValue(result.length, 2, 'The value of result.length is expected to be 2');
assert.sameValue(result[0], firstReturnVal, 'The value of result[0] is expected to equal the value of firstReturnVal');
assert.sameValue(
result[1],
secondReturnVal,
'The value of result[1] is expected to equal the value of secondReturnVal'
);
reportCompare(0, 0);
|
