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// Assigning to the length property of a proxy to an array
// calls the proxy's defineProperty handler.
var a = [0, 1, 2, 3];
var p = new Proxy(a, {
defineProperty(t, id, desc) {
hits++;
// ES6 draft rev 28 (2014 Oct 14) 9.1.9 step 5.e.i.
// Since the property already exists, the system only changes
// the value. desc is otherwise empty.
assertEq(Object.getOwnPropertyNames(desc).join(","), "value");
assertEq(desc.value, 2);
return true;
}
});
var hits = 0;
p.length = 2;
assertEq(hits, 1);
assertEq(a.length, 4);
assertEq(a[2], 2);