The Tor Browser / file revision

 const Cu = Components.utils;

 function run_test() {

   // Make a content sandbox with an Xrayable object.

   // NB: We use an nsEP here so that we can have access to Components, but still

   // have Xray behavior from this scope.

   var contentSB = new Cu.Sandbox(['http://www.google.com'],

                                  { wantGlobalProperties: ["XMLHttpRequest"], wantComponents: true });

   // Make an XHR in the content sandbox.

   Cu.evalInSandbox('xhr = new XMLHttpRequest();', contentSB);

   // Make sure that waivers can be set as Xray expandos.

   var xhr = contentSB.xhr;

   do_check_true(Cu.isXrayWrapper(xhr));

   xhr.unwaivedExpando = xhr;

   do_check_true(Cu.isXrayWrapper(xhr.unwaivedExpando));

   var waived = xhr.wrappedJSObject;

   do_check_true(!Cu.isXrayWrapper(waived));

   xhr.waivedExpando = waived;

   do_check_true(!Cu.isXrayWrapper(xhr.waivedExpando));

   // Try the same thing for getters/setters, even though that's kind of

   // contrived.

   Cu.evalInSandbox('function f() {}', contentSB);

   var f = contentSB.f;

   var fWaiver = Cu.waiveXrays(f);

   do_check_true(f != fWaiver);

   do_check_true(Cu.unwaiveXrays(fWaiver) === f);

   Object.defineProperty(xhr, 'waivedAccessors', {get: fWaiver, set: fWaiver});

   var desc = Object.getOwnPropertyDescriptor(xhr, 'waivedAccessors');

   do_check_true(desc.get === fWaiver);

   do_check_true(desc.set === fWaiver);

   // Make sure we correctly handle same-compartment security wrappers.

   var unwaivedC = contentSB.Components;

   do_check_true(Cu.isXrayWrapper(unwaivedC));

   var waivedC = unwaivedC.wrappedJSObject;

   do_check_true(waivedC && unwaivedC && (waivedC != unwaivedC));

   xhr.waivedC = waivedC;

   do_check_true(xhr.waivedC === waivedC);

   do_check_true(Cu.unwaiveXrays(xhr.waivedC) === unwaivedC);

 }