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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: Creating object with custom constructor (traversed via iterator)
info: |
[...]
6. If usingIterator is not undefined, then
a. If IsConstructor(C) is true, then
i. Let A be Construct(C).
b. Else,
i. Let A be ArrayCreate(0).
c. ReturnIfAbrupt(A).
features: [Symbol.iterator]
---*/
var thisVal, args;
var callCount = 0;
var C = function() {
thisVal = this;
args = arguments;
callCount += 1;
};
var result;
var items = {};
items[Symbol.iterator] = function() {
return {
next: function() {
return {
done: true
};
}
};
};
result = Array.from.call(C, items);
assert(
result instanceof C, 'Constructed value is an instance of the constructor'
);
assert.sameValue(
result.constructor,
C,
'Constructed value correctly defines a `constructor` property'
);
assert.sameValue(callCount, 1, 'Constructor invoked exactly once');
assert.sameValue(thisVal, result, 'Constructed value is returned');
assert.sameValue(args.length, 0, 'Constructor invoked without arguments');
|
