michael@0: let invoked = false;
michael@0: Object.defineProperty(Array.prototype, '0', {set: function () {
michael@0:     invoked = true;
michael@0: }});
michael@0: 
michael@0: let result = [1, 2, 3].slice(1);
michael@0: assertEq(invoked, false);
michael@0: 
michael@0: let proxy = new Proxy({}, {
michael@0:     get: function (target, name, proxy) {
michael@0:         switch (name) {
michael@0:           case "length":
michael@0:             return 2;
michael@0:           case "0":
michael@0:             return 15;
michael@0:           case "1":
michael@0:             // Should not invoke [[Get]] for this hole.
michael@0:           default:
michael@0:             assertEq(false, true);
michael@0:         }
michael@0:     },
michael@0:     has: function (target, name) {
michael@0:         switch (name) {
michael@0:           case "0":
michael@0:             return true;
michael@0:           case "1":
michael@0:             return false;
michael@0:           default:
michael@0:             assertEq(false, true);
michael@0:         }
michael@0:     }
michael@0: })
michael@0: result = Array.prototype.slice.call(proxy, 0);
michael@0: assertEq(result.length, 2);
michael@0: assertEq(0 in result, true);
michael@0: assertEq(1 in result, false);
michael@0: assertEq(result[0], 15);