const Cu = Components.utils; function run_test() { var sb = Cu.Sandbox('http://www.example.com', { wantGlobalProperties: ['XMLHttpRequest']}); var xhr = Cu.evalInSandbox('new XMLHttpRequest()', sb); do_check_eq(xhr.toString(), '[object XMLHttpRequest]'); do_check_eq((new sb.Object()).toString(), '[object Object]'); do_check_eq(sb.Object.prototype.toString.call(new sb.Uint16Array()), '[object Uint16Array]'); }