The Tor Browser: js/src/jit-test/tests/arrays/slice.js@6474c204b198

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 let invoked = false;

     2 Object.defineProperty(Array.prototype, '0', {set: function () {

     3     invoked = true;

     4 }});

     6 let result = [1, 2, 3].slice(1);

     7 assertEq(invoked, false);

     9 let proxy = new Proxy({}, {

    10     get: function (target, name, proxy) {

    11         switch (name) {

    12           case "length":

    13             return 2;

    14           case "0":

    15             return 15;

    16           case "1":

    17             // Should not invoke [[Get]] for this hole.

    18           default:

    19             assertEq(false, true);

    20         }

    21     },

    22     has: function (target, name) {

    23         switch (name) {

    24           case "0":

    25             return true;

    26           case "1":

    27             return false;

    28           default:

    29             assertEq(false, true);

    30         }

    31     }

    32 })

    33 result = Array.prototype.slice.call(proxy, 0);

    34 assertEq(result.length, 2);

    35 assertEq(0 in result, true);

    36 assertEq(1 in result, false);

    37 assertEq(result[0], 15);

The Tor Browser / file revision