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for (var constructor of anyTypedArrayConstructors) {
// %TypedArray%.from works on arguments objects.
(function () {
assertDeepEq(constructor.from(arguments), new constructor(["0", "1", undefined]));
})("0", "1", undefined);
// If an object has both .length and [@@iterator] properties, [@@iterator] is used.
var a = ['0', '1', '2', '3', '4'];
a[Symbol.iterator] = function* () {
for (var i = 5; i--; )
yield this[i];
};
var log = '';
function f(x) {
log += x;
return x + x;
}
var b = constructor.from(a, f);
assertDeepEq(b, new constructor(['44', '33', '22', '11', '00']));
assertEq(log, '43210');
// In fact, if [@@iterator] is present, .length isn't queried at all.
var pa = new Proxy(a, {
has: function (target, id) {
if (id === "length")
throw new Error(".length should not be queried (has)");
return id in target;
},
get: function (target, id) {
if (id === "length")
throw new Error(".length should not be queried (get)");
return target[id];
},
getOwnPropertyDescriptor: function (target, id) {
if (id === "length")
throw new Error(".length should not be queried (getOwnPropertyDescriptor)");
return Object.getOwnPropertyDescriptor(target, id)
}
});
log = "";
b = constructor.from(pa, f);
assertDeepEq(b, new constructor(['44', '33', '22', '11', '00']));
assertEq(log, '43210');
}
if (typeof reportCompare === "function")
reportCompare(true, true);
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