Bug 983619 - Add Window.getInterface/QueryInterface to WebIDL. r=bz.

content/base/src/nsXMLHttpRequest.cpp

@@ -3638,17 +3638,7 @@ nsXMLHttpRequest::GetInterface(const nsIID & aIID, void **aResult)
 JS::Value
 nsXMLHttpRequest::GetInterface(JSContext* aCx, nsIJSID* aIID, ErrorResult& aRv)
 {
-  const nsID* iid = aIID->GetID();
-  nsCOMPtr<nsISupports> result;
-  JS::Rooted<JS::Value> v(aCx, JSVAL_NULL);
-  aRv = GetInterface(*iid, getter_AddRefs(result));
-  NS_ENSURE_FALSE(aRv.Failed(), JSVAL_NULL);
-
-  JS::Rooted<JSObject*> wrapper(aCx, GetWrapper());
-  JSAutoCompartment ac(aCx, wrapper);
-  JS::Rooted<JSObject*> global(aCx, JS_GetGlobalForObject(aCx, wrapper));
-  aRv = nsContentUtils::WrapNative(aCx, global, result, iid, &v);
-  return aRv.Failed() ? JSVAL_NULL : v;
+  return dom::GetInterface(aCx, this, aIID, aRv);
 }
 
 nsXMLHttpRequestUpload*

dom/base/nsGlobalWindow.cpp

@@ -10384,6 +10384,12 @@ nsGlobalWindow::GetInterface(const nsIID & aIID, void **aSink)
   return *aSink ? NS_OK : NS_ERROR_NO_INTERFACE;
 }
 
+JS::Value
+nsGlobalWindow::GetInterface(JSContext* aCx, nsIJSID* aIID, ErrorResult& aError)
+{
+  return dom::GetInterface(aCx, this, aIID, aError);
+}
+
 void
 nsGlobalWindow::FireOfflineStatusEvent()
 {

dom/base/nsGlobalWindow.h

@@ -84,6 +84,7 @@ class nsIDOMCrypto;
 class nsIDOMOfflineResourceList;
 class nsIScrollableFrame;
 class nsIControllers;
+class nsIJSID;
 class nsIScriptContext;
 class nsIScriptTimeoutHandler;
 class nsIWebBrowserChrome;
@@ -979,6 +980,9 @@ public:
                        mozilla::dom::Element* aPanel,
                        mozilla::ErrorResult& aError);
 
+  JS::Value GetInterface(JSContext* aCx, nsIJSID* aIID,
+                         mozilla::ErrorResult& aError);
+
 protected:
   // Array of idle observers that are notified of idle events.
   nsTObserverArray<IdleObserverHolder> mIdleObservers;

dom/bindings/BindingUtils.cpp

@@ -814,13 +814,20 @@ QueryInterface(JSContext* cx, unsigned argc, JS::Value* vp)
   // Get the object. It might be a security wrapper, in which case we do a checked
   // unwrap.
   JS::Rooted<JSObject*> origObj(cx, &thisv.toObject());
-  JSObject* obj = js::CheckedUnwrap(origObj);
+  JSObject* obj = js::CheckedUnwrap(origObj, /* stopAtOuter = */ false);
   if (!obj) {
       JS_ReportError(cx, "Permission denied to access object");
       return false;
   }
 
-  nsISupports* native = UnwrapDOMObjectToISupports(obj);
+  // Switch this to UnwrapDOMObjectToISupports once our global objects are
+  // using new bindings.
+  JS::Rooted<JS::Value> val(cx, JS::ObjectValue(*obj));
+  nsISupports* native = nullptr;
+  nsCOMPtr<nsISupports> nativeRef;
+  xpc_qsUnwrapArg<nsISupports>(cx, val, &native,
+                               static_cast<nsISupports**>(getter_AddRefs(nativeRef)),
+                               &val);
   if (!native) {
     return Throw(cx, NS_ERROR_FAILURE);
   }
@@ -861,6 +868,30 @@ QueryInterface(JSContext* cx, unsigned argc, JS::Value* vp)
   return true;
 }
 
+JS::Value
+GetInterfaceImpl(JSContext* aCx, nsIInterfaceRequestor* aRequestor,
+                 nsWrapperCache* aCache, nsIJSID* aIID, ErrorResult& aError)
+{
+  const nsID* iid = aIID->GetID();
+
+  nsCOMPtr<nsISupports> result;
+  JS::Rooted<JS::Value> v(aCx, JSVAL_NULL);
+  aError = aRequestor->GetInterface(*iid, getter_AddRefs(result));
+  if (aError.Failed()) {
+    return JS::NullValue();
+  }
+
+  JS::Rooted<JSObject*> wrapper(aCx, aCache->GetWrapper());
+  JSAutoCompartment ac(aCx, wrapper);
+  JS::Rooted<JSObject*> global(aCx, JS_GetGlobalForObject(aCx, wrapper));
+  aError = nsContentUtils::WrapNative(aCx, global, result, iid, &v);
+  if (aError.Failed()) {
+    return JS::NullValue();
+  }
+
+  return v;
+}
+
 bool
 ThrowingConstructor(JSContext* cx, unsigned argc, JS::Value* vp)
 {

dom/bindings/BindingUtils.h

@@ -34,6 +34,7 @@
 
 #include "nsWrapperCacheInlines.h"
 
+class nsIJSID;
 class nsPIDOMWindow;
 
 extern nsresult
@@ -1464,6 +1465,17 @@ WantsQueryInterface
   }
 };
 
+JS::Value
+GetInterfaceImpl(JSContext* aCx, nsIInterfaceRequestor* aRequestor,
+                 nsWrapperCache* aCache, nsIJSID* aIID, ErrorResult& aError);
+
+template<class T>
+JS::Value
+GetInterface(JSContext* aCx, T* aThis, nsIJSID* aIID, ErrorResult& aError)
+{
+  return GetInterfaceImpl(aCx, aThis, aThis, aIID, aError);
+}
+
 bool
 ThrowingConstructor(JSContext* cx, unsigned argc, JS::Value* vp);
 

dom/tests/mochitest/general/test_interfaces.html

@@ -1216,11 +1216,11 @@ function createInterfaceMap(isXBLScope) {
 
   var interfaceMap = {};
 
-  function addInterfaces(interfaces, shouldExpect)
+  function addInterfaces(interfaces)
   {
     for (var entry of interfaces) {
       if (typeof(entry) === "string") {
-        interfaceMap[entry] = shouldExpect;
+        interfaceMap[entry] = true;
       } else if ((entry.nightly === !isNightly) ||
                  (entry.xbl === !isXBLScope) ||
                  (entry.desktop === !isDesktop) ||
@@ -1230,13 +1230,19 @@ function createInterfaceMap(isXBLScope) {
                  (entry.permission && !hasPermission(entry.permission))) {
         interfaceMap[entry.name] = false;
       } else {
-        interfaceMap[entry.name] = shouldExpect;
+        interfaceMap[entry.name] = true;
       }
     }
   }
 
-  addInterfaces(ecmaGlobals, true);
-  addInterfaces(interfaceNamesInGlobalScope, true);
+  addInterfaces(ecmaGlobals);
+  addInterfaces(interfaceNamesInGlobalScope);
+  if (isXBLScope) {
+    // We expose QueryInterface to XBL scopes. It's not an interface but we
+    // need to handle it because it's an own property of the global and the
+    // property name starts with an uppercase letter.
+    interfaceMap["QueryInterface"] = true;
+  }
 
   return interfaceMap;
 }

dom/webidl/LegacyQueryInterface.webidl

@@ -88,6 +88,7 @@ TreeWalker implements LegacyQueryInterface;
 UndoManager implements LegacyQueryInterface;
 ValidityState implements LegacyQueryInterface;
 WebSocket implements LegacyQueryInterface;
+Window implements LegacyQueryInterface;
 XMLHttpRequest implements LegacyQueryInterface;
 XMLHttpRequestUpload implements LegacyQueryInterface;
 XMLSerializer implements LegacyQueryInterface;

dom/webidl/Window.webidl

@@ -16,6 +16,7 @@
  */
 
 interface ApplicationCache;
+interface IID;
 interface MozFrameRequestCallback;
 interface nsIBrowserDOMWindow;
 interface nsIMessageBroadcaster;
@@ -336,6 +337,8 @@ partial interface Window {
   [Replaceable, Throws] readonly attribute object? content;
 
   [ChromeOnly, Throws] readonly attribute object? __content;
+
+  [Throws, ChromeOnly] any getInterface(IID iid);
 };
 
 Window implements TouchEventHandlers;