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// Assigning to a proxy with no set handler calls the defineProperty handler
// when an existing own data property already exists on the target.
var t = {x: 1};
var p = new Proxy(t, {
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, 42);
return true;
}
});
var hits = 0;
p.x = 42;
assertEq(hits, 1);
assertEq(t.x, 1);