bool WindowProxy::setupWindowPrototypeChain() {
// Associate the window wrapper object and its prototype chain with the
// corresponding native DOMWindow object.
// The full structure of the global object's prototype chain is as follows:
//
// global proxy object [1]
// -- has prototype --> global object (window wrapper object) [2]
// -- has prototype --> Window.prototype
// -- has prototype --> WindowProperties [3]
// -- has prototype --> EventTarget.prototype
// -- has prototype --> Object.prototype
// -- has prototype --> null
//
// [1] Global proxy object is as known as "outer global object". It's an
// empty object and remains after navigation. When navigated, points to
// a different global object as the prototype object.
// [2] Global object is as known as "inner global object" or "window wrapper
// object". The prototype chain between global proxy object and global
// object is NOT observable from user JavaScript code. All other
// prototype chains are observable. Global proxy object and global object
// together appear to be the same single JavaScript object. See also:
// https://wiki.mozilla.org/Gecko:SplitWindow
// global object (= window wrapper object) provides most of Window's DOM
// attributes and operations. Also global variables defined by user
// JavaScript are placed on this object. When navigated, a new global
// object is created together with a new v8::Context, but the global proxy
// object doesn't change.
// [3] WindowProperties is a named properties object of Window interface.
DOMWindow* window = m_frame->domWindow();
const WrapperTypeInfo* wrapperTypeInfo = window->wrapperTypeInfo();
v8::Local<v8::Context> context = m_scriptState->context();
// The global proxy object. Note this is not the global object.
v8::Local<v8::Object> globalProxy = context->Global();
// The global object, aka window wrapper object.
v8::Local<v8::Object> windowWrapper =
globalProxy->GetPrototype().As<v8::Object>();
windowWrapper = V8DOMWrapper::associateObjectWithWrapper(
m_isolate, window, wrapperTypeInfo, windowWrapper);
// The prototype object of Window interface.
v8::Local<v8::Object> windowPrototype =
windowWrapper->GetPrototype().As<v8::Object>();
RELEASE_ASSERT(!windowPrototype.IsEmpty());
V8DOMWrapper::setNativeInfo(m_isolate, windowPrototype, wrapperTypeInfo,
window);
// The named properties object of Window interface.
v8::Local<v8::Object> windowProperties =
windowPrototype->GetPrototype().As<v8::Object>();
RELEASE_ASSERT(!windowProperties.IsEmpty());
V8DOMWrapper::setNativeInfo(m_isolate, windowProperties, wrapperTypeInfo,
window);
// TODO(keishi): Remove installPagePopupController and implement
// PagePopupController in another way.
V8PagePopupControllerBinding::installPagePopupController(context,
windowWrapper);
return true;
}
bool WindowProxy::installDOMWindow()
{
DOMWindow* window = m_frame->domWindow();
const WrapperTypeInfo* wrapperTypeInfo = window->wrapperTypeInfo();
v8::Local<v8::Object> windowWrapper;
v8::Local<v8::Function> constructor = m_scriptState->perContextData()->constructorForType(wrapperTypeInfo);
if (constructor.IsEmpty())
return false;
if (!V8ObjectConstructor::newInstance(m_isolate, constructor).ToLocal(&windowWrapper))
return false;
windowWrapper = V8DOMWrapper::associateObjectWithWrapper(m_isolate, window, wrapperTypeInfo, windowWrapper);
V8DOMWrapper::setNativeInfo(v8::Local<v8::Object>::Cast(windowWrapper->GetPrototype()), wrapperTypeInfo, window);
// Install the windowWrapper as the prototype of the innerGlobalObject.
// The full structure of the global object is as follows:
//
// outerGlobalObject (Empty object, remains after navigation)
// -- has prototype --> innerGlobalObject (Holds global variables, changes during navigation)
// -- has prototype --> DOMWindow instance
// -- has prototype --> Window.prototype
// -- has prototype --> EventTarget.prototype
// -- has prototype --> Object.prototype
//
// Note: Much of this prototype structure is hidden from web content. The
// outer, inner, and DOMWindow instance all appear to be the same
// JavaScript object.
v8::Local<v8::Context> context = m_scriptState->context();
v8::Local<v8::Object> innerGlobalObject = toInnerGlobalObject(m_scriptState->context());
V8DOMWrapper::setNativeInfo(innerGlobalObject, wrapperTypeInfo, window);
if (!v8CallBoolean(innerGlobalObject->SetPrototype(context, windowWrapper)))
return false;
// TODO(keishi): Remove installPagePopupController and implement
// PagePopupController in another way.
V8PagePopupControllerBinding::installPagePopupController(context, windowWrapper);
return true;
}