Backed out changeset 8cb8888c68d3 due to failing mochitests.

js/src/jsinterp.cpp

@@ -371,17 +371,11 @@ js_GetPrimitiveThis(JSContext *cx, jsval *vp, JSClass *clasp, jsval *thisvp)
 
 /* Some objects (e.g., With) delegate 'this' to another object. */
 static inline JSObject *
-CallThisObjectHook(JSContext *cx, JSObject *obj, JSObject *scope, jsval *argv)
+CallThisObjectHook(JSContext *cx, JSObject *obj, jsval *argv)
 {
-    JSObject *thisp = obj;
+    JSObject *thisp = obj->thisObject(cx);
-    if (JSThisObjectOp thisObject = obj->map->ops->thisObject) {
+    if (!thisp)
-        if (!scope)
+        return NULL;
-            scope = JSVAL_TO_OBJECT(argv[-2])->getGlobal();
-        thisp = thisObject(cx, obj, scope);
-        if (!thisp)
-            return NULL;
-    }
-
     argv[-1] = OBJECT_TO_JSVAL(thisp);
     return thisp;
 }
@@ -404,29 +398,45 @@ CallThisObjectHook(JSContext *cx, JSObject *obj, JSObject *scope, jsval *argv)
 JS_STATIC_INTERPRET JSObject *
 js_ComputeGlobalThis(JSContext *cx, jsval *argv)
 {
-    JSObject *thisp = JSVAL_TO_OBJECT(argv[-2])->getGlobal();
+    JSObject *thisp;
-    return CallThisObjectHook(cx, thisp, thisp, argv);
+
+    if (JSVAL_IS_PRIMITIVE(argv[-2]) ||
+        !JSVAL_TO_OBJECT(argv[-2])->getParent()) {
+        thisp = cx->globalObject;
+    } else {
+        thisp = JSVAL_TO_OBJECT(argv[-2])->getGlobal();
+    }
+
+    return CallThisObjectHook(cx, thisp, argv);
+}
+
+static JSObject *
+ComputeThis(JSContext *cx, jsval *argv)
+{
+    JSObject *thisp;
+
+    JS_ASSERT(!JSVAL_IS_NULL(argv[-1]));
+    if (!JSVAL_IS_OBJECT(argv[-1])) {
+        if (!js_PrimitiveToObject(cx, &argv[-1]))
+            return NULL;
+        thisp = JSVAL_TO_OBJECT(argv[-1]);
+        return thisp;
+    } 
+
+    thisp = JSVAL_TO_OBJECT(argv[-1]);
+    if (thisp->getClass() == &js_CallClass || thisp->getClass() == &js_BlockClass)
+        return js_ComputeGlobalThis(cx, argv);
+
+    return CallThisObjectHook(cx, thisp, argv);
 }
 
 JSObject *
 js_ComputeThis(JSContext *cx, jsval *argv)
 {
     JS_ASSERT(argv[-1] != JSVAL_HOLE);  // check for SynthesizeFrame poisoning
-
     if (JSVAL_IS_NULL(argv[-1]))
         return js_ComputeGlobalThis(cx, argv);
-
+    return ComputeThis(cx, argv);
-    if (!JSVAL_IS_OBJECT(argv[-1])) {
-        if (!js_PrimitiveToObject(cx, &argv[-1]))
-            return NULL;
-        return JSVAL_TO_OBJECT(argv[-1]);
-    } 
-
-    JSObject *thisp = JSVAL_TO_OBJECT(argv[-1]);
-    if (thisp->getClass() == &js_CallClass || thisp->getClass() == &js_BlockClass)
-        return js_ComputeGlobalThis(cx, argv);
-
-    return CallThisObjectHook(cx, thisp, NULL, argv);
 }
 
 #if JS_HAS_NO_SUCH_METHOD
@@ -1048,7 +1058,7 @@ js_Execute(JSContext *cx, JSObject *chain, JSScript *script,
             return false;
         frame.scopeChain = chain;
 
-        JSObject *thisp = JSVAL_TO_OBJECT(frame.thisv)->thisObject(cx, chain);
+        JSObject *thisp = JSVAL_TO_OBJECT(frame.thisv)->thisObject(cx);
         if (!thisp)
             return false;
         frame.thisv = OBJECT_TO_JSVAL(thisp);

js/src/jsobj.cpp

@@ -2947,12 +2947,12 @@ with_TypeOf(JSContext *cx, JSObject *obj)
 }
 
 static JSObject *
-with_ThisObject(JSContext *cx, JSObject *obj, JSObject *scope)
+with_ThisObject(JSContext *cx, JSObject *obj)
 {
     JSObject *proto = obj->getProto();
     if (!proto)
         return obj;
-    return proto->thisObject(cx, scope);
+    return proto->thisObject(cx);
 }
 
 JS_FRIEND_DATA(JSObjectOps) js_WithObjectOps = {

js/src/jsobj.h

@@ -161,7 +161,7 @@ struct JSObjectOps {
     JSTraceOp           trace;
 
     /* Optionally non-null members start here. */
-    JSThisObjectOp      thisObject;
+    JSObjectOp          thisObject;
     JSPropertyRefOp     dropProperty;
     JSNative            call;
     JSNative            construct;
@@ -634,8 +634,8 @@ struct JSObject {
     }
 
     /* These four are time-optimized to avoid stub calls. */
-    JSObject *thisObject(JSContext *cx, JSObject *scope) {
+    JSObject *thisObject(JSContext *cx) {
-        return map->ops->thisObject ? map->ops->thisObject(cx, this, scope) : this;
+        return map->ops->thisObject ? map->ops->thisObject(cx, this) : this;
     }
 
     void dropProperty(JSContext *cx, JSProperty *prop) {

js/src/jspubtd.h

@@ -423,19 +423,9 @@ typedef JSBool
 (* JSEqualityOp)(JSContext *cx, JSObject *obj, jsval v, JSBool *bp);
 
 /*
- * The type of JSObjectOps::thisObject. Return a "stunt this" object for obj,
+ * A generic type for functions mapping an object to another object, or null
- * having a parent chain that ends in scope; or NULL on error.
+ * if an error or exception was thrown on cx.  Used by JSObjectOps.thisObject
- *
+ * at present.
- * The engine guarantees that obj->map->ops->thisObject == the callback
- * and that cx, obj, and scope are non-null.
- */
-typedef JSObject *
-(* JSThisObjectOp)(JSContext *cx, JSObject *obj, JSObject *scope);
-
-/*
- * A generic type for functions mapping an object to another object, or null if
- * an error or exception was thrown on cx. Used by JSObjectOps.innerObject and
- * outerObject at present.
  */
 typedef JSObject *
 (* JSObjectOp)(JSContext *cx, JSObject *obj);

js/src/jstracer.cpp

@@ -9516,7 +9516,7 @@ TraceRecorder::getThis(LIns*& this_ins)
 
     this_ins = get(&thisv);
 
-    JSObject* wrappedGlobal = globalObj->thisObject(cx, globalObj);
+    JSObject* wrappedGlobal = globalObj->thisObject(cx);
     if (!wrappedGlobal)
         RETURN_ERROR("globalObj->thisObject hook threw in getThis");
 

js/src/shell/js.cpp

@@ -2763,7 +2763,7 @@ split_outerObject(JSContext *cx, JSObject *obj)
 }
 
 static JSObject *
-split_thisObject(JSContext *cx, JSObject *obj, JSObject */*scope*/)
+split_thisObject(JSContext *cx, JSObject *obj)
 {
     OBJ_TO_OUTER_OBJECT(cx, obj);
     if (!obj)

js/src/xpconnect/src/xpcJSWeakReference.cpp

@@ -133,16 +133,13 @@ xpcJSWeakReference::Get()
             // nsXPConnect::GetWrapperForObject. But it takes a lot of
             // arguments! It turns out that the thisObject hook on XPConnect
             // objects does the right thing though, so...
-            if (obj->map->ops->thisObject)
+
+            if (obj->map->ops->thisObject &&
+                !(obj = obj->map->ops->thisObject(cx, obj)))
             {
-                JSObject *scope = JS_GetScopeChain(cx);
+                return NS_ERROR_FAILURE;
-                if (!scope)
-                    return NS_ERROR_FAILURE;
-                scope = JS_GetGlobalForObject(cx, scope);
-                obj = obj->map->ops->thisObject(cx, obj, scope);
-                if (!obj)
-                    return NS_ERROR_FAILURE;
             }
+
             *retval = OBJECT_TO_JSVAL(obj);
         }
     }

js/src/xpconnect/src/xpcwrappednativejsops.cpp

@@ -1477,7 +1477,7 @@ private:
 } // namespace
 
 static JSObject*
-XPC_WN_JSOp_ThisObject(JSContext *cx, JSObject *obj, JSObject *scope)
+XPC_WN_JSOp_ThisObject(JSContext *cx, JSObject *obj)
 {
     // None of the wrappers we could potentially hand out are threadsafe so
     // just hand out the given object.
@@ -1488,6 +1488,15 @@ XPC_WN_JSOp_ThisObject(JSContext *cx, JSObject *obj, JSObject *scope)
     if(!obj)
         return nsnull;
 
+    JSObject *scope = JS_GetScopeChain(cx);
+    if(!scope)
+    {
+        XPCThrower::Throw(NS_ERROR_FAILURE, cx);
+        return nsnull;
+    }
+
+    scope = JS_GetGlobalForObject(cx, scope);
+
     XPCPerThreadData *threadData = XPCPerThreadData::GetData(cx);
     if(!threadData)
     {