function run_test() { var sb = new Cu.Sandbox('http://www.example.com'); sb.obj = {}; sb.arr = []; sb.fun = function() {}; Assert.ok(sb.eval('Object.getPrototypeOf(obj) == null')); Assert.ok(sb.eval('Object.getPrototypeOf(arr) == null')); Assert.ok(sb.eval('Object.getPrototypeOf(fun) == null')); }