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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
es6id: 22.1.2.1
description: >
Arguments of 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 args = [];
var firstResult = {
done: false,
value: {}
};
var secondResult = {
done: false,
value: {}
};
var mapFn = function(value, idx) {
args.push(arguments);
};
var items = {};
var nextResult = firstResult;
var nextNextResult = secondResult;
items[Symbol.iterator] = function() {
return {
next: function() {
var result = nextResult;
nextResult = nextNextResult;
nextNextResult = {
done: true
};
return result;
}
};
};
Array.from(items, mapFn);
assert.sameValue(args.length, 2, 'Iteration count');
assert.sameValue(args[0].length, 2, 'First iteration: arguments length');
assert.sameValue(
args[0][0], firstResult.value, 'First iteration: first argument'
);
assert.sameValue(args[0][1], 0, 'First iteration: second argument');
assert.sameValue(args[1].length, 2, 'Second iteration: arguments length');
assert.sameValue(
args[1][0], secondResult.value, 'Second iteration: first argument'
);
assert.sameValue(args[1][1], 1, 'Second iteration: second argument');
|
