bug 488285 - fixing strict mode warnings with DOm window object. r=brendan

dom/base/nsDOMClassInfo.cpp

@@ -6527,10 +6527,8 @@ nsWindowSH::NewResolve(nsIXPConnectWrappedNative *wrapper, JSContext *cx,
   // binding a name) a new undefined property that's not already
   // defined on our prototype chain. This way we can access this
   // expando w/o ever getting back into XPConnect.
-  JSStackFrame *fp = NULL;
   if ((flags & JSRESOLVE_ASSIGNING) &&
       !(flags & JSRESOLVE_WITH) &&
-      !(JS_FrameIterator(cx, &fp) && fp->regs && (JSOp)*fp->regs->pc == JSOP_BINDNAME) &&
       win->IsInnerWindow()) {
     JSObject *realObj;
     wrapper->GetJSObject(&realObj);
@@ -6564,9 +6562,14 @@ nsWindowSH::NewResolve(nsIXPConnectWrappedNative *wrapper, JSContext *cx,
       // We don't need to worry about property attributes here as we
       // know here we're dealing with an undefined property set, so
       // we're not declaring readonly or permanent properties.
+      //
+      // Since we always create the undeclared property here without given a
+      // chance for the interpreter to report applicable strict mode warnings,
+      // we must take care to check those warnings here.
 
       JSString *str = JSVAL_TO_STRING(id);
-      if (!::JS_DefineUCProperty(cx, obj, ::JS_GetStringChars(str),
+      if (!::js_CheckUndeclaredVarAssignment(cx) ||
+          !::JS_DefineUCProperty(cx, obj, ::JS_GetStringChars(str),
                                  ::JS_GetStringLength(str), JSVAL_VOID,
                                  JS_PropertyStub, JS_PropertyStub,
                                  JSPROP_ENUMERATE)) {

js/src/jsinterp.cpp

@@ -4776,10 +4776,8 @@ js_Interpret(JSContext *cx)
                     LOAD_ATOM(0);
                 id = ATOM_TO_JSID(atom);
                 if (entry) {
-                    if (!js_SetPropertyHelper(cx, obj, id, op == JSOP_SETNAME,
-                                              &rval, &entry)) {
+                    if (!js_SetPropertyHelper(cx, obj, id, &rval, &entry))
                         goto error;
-                    }
 #ifdef JS_TRACER
                     if (entry)
                         TRACE_1(SetPropMiss, entry);
@@ -6433,7 +6431,7 @@ js_Interpret(JSContext *cx)
                     goto error;
                 }
                 if (JS_UNLIKELY(atom == cx->runtime->atomState.protoAtom)
-                    ? !js_SetPropertyHelper(cx, obj, id, false, &rval, &entry)
+                    ? !js_SetPropertyHelper(cx, obj, id, &rval, &entry)
                     : !js_DefineNativeProperty(cx, obj, id, rval, NULL, NULL,
                                                JSPROP_ENUMERATE, 0, 0, NULL,
                                                &entry)) {

js/src/jsobj.cpp

@@ -4379,9 +4379,30 @@ js_GetMethod(JSContext *cx, JSObject *obj, jsid id, jsval *vp,
     return OBJ_GET_PROPERTY(cx, obj, id, vp);
 }
 
+JS_FRIEND_API(JSBool)
+js_CheckUndeclaredVarAssignment(JSContext *cx)
+{
+    JSStackFrame *fp;
+    if (!JS_HAS_STRICT_OPTION(cx) ||
+        !(fp = js_GetTopStackFrame(cx)) ||
+        !fp->regs ||
+        js_GetOpcode(cx, fp->script, fp->regs->pc) != JSOP_SETNAME) {
+        return JS_TRUE;
+    }
+
+    JSAtom *atom;
+    GET_ATOM_FROM_BYTECODE(fp->script, fp->regs->pc, 0, atom);
+
+    const char *bytes = js_AtomToPrintableString(cx, atom);
+    return bytes &&
+           JS_ReportErrorFlagsAndNumber(cx, JSREPORT_WARNING | JSREPORT_STRICT,
+                                        js_GetErrorMessage, NULL,
+                                        JSMSG_UNDECLARED_VAR, bytes);
+}
+
 JSBool
-js_SetPropertyHelper(JSContext *cx, JSObject *obj, jsid id,
-                     JSBool unqualified, jsval *vp, JSPropCacheEntry **entryp)
+js_SetPropertyHelper(JSContext *cx, JSObject *obj, jsid id, jsval *vp,
+                     JSPropCacheEntry **entryp)
 {
     uint32 shape;
     int protoIndex;
@@ -4420,19 +4441,8 @@ js_SetPropertyHelper(JSContext *cx, JSObject *obj, jsid id,
         /* We should never add properties to lexical blocks.  */
         JS_ASSERT(OBJ_GET_CLASS(cx, obj) != &js_BlockClass);
 
-        if (unqualified && !OBJ_GET_PARENT(cx, obj) &&
-            JS_HAS_STRICT_OPTION(cx)) {
-            JSString *str = JSVAL_TO_STRING(ID_TO_VALUE(id));
-            const char *bytes = js_GetStringBytes(cx, str);
-            if (!bytes ||
-                !JS_ReportErrorFlagsAndNumber(cx,
-                                              JSREPORT_WARNING |
-                                              JSREPORT_STRICT,
-                                              js_GetErrorMessage, NULL,
-                                              JSMSG_UNDECLARED_VAR, bytes)) {
-                return NULL;
-            }
-        }
+        if (!OBJ_GET_PARENT(cx, obj) && !js_CheckUndeclaredVarAssignment(cx))
+            return NULL;
     }
     sprop = (JSScopeProperty *) prop;
 
@@ -4607,7 +4617,7 @@ js_SetPropertyHelper(JSContext *cx, JSObject *obj, jsid id,
 JSBool
 js_SetProperty(JSContext *cx, JSObject *obj, jsid id, jsval *vp)
 {
-    return js_SetPropertyHelper(cx, obj, id, false, vp, NULL);
+    return js_SetPropertyHelper(cx, obj, id, vp, NULL);
 }
 
 JSBool

js/src/jsobj.h

@@ -711,9 +711,16 @@ extern JSBool
 js_GetMethod(JSContext *cx, JSObject *obj, jsid id, jsval *vp,
              JSPropCacheEntry **entryp);
 
+/*
+ * Check whether it is OK to assign an undeclared property of the global
+ * object at the current script PC.
+ */
+extern JS_FRIEND_API(JSBool)
+js_CheckUndeclaredVarAssignment(JSContext *cx);
+
 extern JSBool
-js_SetPropertyHelper(JSContext *cx, JSObject *obj, jsid id,
-                     JSBool unqualified, jsval *vp, JSPropCacheEntry **entryp);
+js_SetPropertyHelper(JSContext *cx, JSObject *obj, jsid id, jsval *vp,
+                     JSPropCacheEntry **entryp);
 
 extern JSBool
 js_SetProperty(JSContext *cx, JSObject *obj, jsid id, jsval *vp);