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