Revert "Implement Object.getNotifier(obj).performChange()" (r14696)

src/object-observe.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 48 matching lines @@
 var observerInfoMap =
     new ObservationWeakMap(observationState.observerInfoMap);
 var objectInfoMap = new ObservationWeakMap(observationState.objectInfoMap);
 var notifierTargetMap =
     new ObservationWeakMap(observationState.notifierTargetMap);
 
 function CreateObjectInfo(object) {
   var info = {
     changeObservers: new InternalArray,
     notifier: null,
-    inactiveObservers: new InternalArray,
-    performing: { __proto__: null },
-    performingCount: 0,
   };
   objectInfoMap.set(object, info);
   return info;
 }
 
-var defaultAcceptTypes = {
-  __proto__: null,
-  'new': true,
-  'updated': true,
-  'deleted': true,
-  'prototype': true,
-  'reconfigured': true
-};
-
-function CreateObserver(callback, accept) {
-  var observer = {
-    __proto__: null,
-    callback: callback,
-    accept: defaultAcceptTypes
-  };
-
-  if (IS_UNDEFINED(accept))
-    return observer;
-
-  var acceptMap = { __proto__: null };
-  for (var i = 0; i < accept.length; i++)
-    acceptMap[accept[i]] = true;
-
-  observer.accept = acceptMap;
-  return observer;
-}
-
-function ObserverIsActive(observer, objectInfo) {
-  if (objectInfo.performingCount === 0)
-    return true;
-
-  var performing = objectInfo.performing;
-  for (var type in performing) {
-    if (performing[type] > 0 && observer.accept[type])
-      return false;
-  }
-
-  return true;
-}
-
-function ObserverIsInactive(observer, objectInfo) {
-  return !ObserverIsActive(observer, objectInfo);
-}
-
-function RemoveNullElements(from) {
-  var i = 0;
-  var j = 0;
-  for (; i < from.length; i++) {
-    if (from[i] === null)
-      continue;
-    if (j < i)
-      from[j] = from[i];
-    j++;
-  }
-
-  if (i !== j)
-    from.length = from.length - (i - j);
-}
-
-function RepartitionObservers(conditionFn, from, to, objectInfo) {
-  var anyRemoved = false;
-  for (var i = 0; i < from.length; i++) {
-    var observer = from[i];
-    if (conditionFn(observer, objectInfo)) {
-      anyRemoved = true;
-      from[i] = null;
-      to.push(observer);
-    }
-  }
-
-  if (anyRemoved)
-    RemoveNullElements(from);
-}
-
-function BeginPerformChange(objectInfo, type) {
-  objectInfo.performing[type] = (objectInfo.performing[type] || 0) + 1;
-  objectInfo.performingCount++;
-  RepartitionObservers(ObserverIsInactive,
-                       objectInfo.changeObservers,
-                       objectInfo.inactiveObservers,
-                       objectInfo);
-}
-
-function EndPerformChange(objectInfo, type) {
-  objectInfo.performing[type]--;
-  objectInfo.performingCount--;
-  RepartitionObservers(ObserverIsActive,
-                       objectInfo.inactiveObservers,
-                       objectInfo.changeObservers,
-                       objectInfo);
-}
-
-function ensureObserverRemoved(objectInfo, callback) {
-  function remove(observerList) {
-    for (var i = 0; i < observerList.length; i++) {
-      if (observerList[i].callback === callback) {
-        observerList.splice(i, 1);
-        return true;
-      }
-    }
-    return false;
-  }
-
-  if (!remove(objectInfo.changeObservers))
-    remove(objectInfo.inactiveObservers);
-}
-
-function AcceptArgIsValid(arg) {
-  if (IS_UNDEFINED(arg))
-    return true;
-
-  if (!IS_SPEC_OBJECT(arg) ||
-      !IS_NUMBER(arg.length) ||
-      arg.length < 0)
-    return false;
-
-  var length = arg.length;
-  for (var i = 0; i < length; i++) {
-    if (!IS_STRING(arg[i]))
-      return false;
-  }
-  return true;
-}
-
-function ObjectObserve(object, callback, accept) {
+function ObjectObserve(object, callback) {
   if (!IS_SPEC_OBJECT(object))
     throw MakeTypeError("observe_non_object", ["observe"]);
   if (!IS_SPEC_FUNCTION(callback))
     throw MakeTypeError("observe_non_function", ["observe"]);
   if (ObjectIsFrozen(callback))
     throw MakeTypeError("observe_callback_frozen");
-  if (!AcceptArgIsValid(accept))
-    throw MakeTypeError("observe_accept_invalid");
 
   if (!observerInfoMap.has(callback)) {
     observerInfoMap.set(callback, {
       pendingChangeRecords: null,
       priority: observationState.observerPriority++,
     });
   }
 
   var objectInfo = objectInfoMap.get(object);
   if (IS_UNDEFINED(objectInfo)) objectInfo = CreateObjectInfo(object);
   %SetIsObserved(object, true);
 
-  ensureObserverRemoved(objectInfo, callback);
-
-  var observer = CreateObserver(callback, accept);
-  if (ObserverIsActive(observer, objectInfo))
-    objectInfo.changeObservers.push(observer);
-  else
-    objectInfo.inactiveObservers.push(observer);
+  var changeObservers = objectInfo.changeObservers;
+  if (changeObservers.indexOf(callback) < 0) changeObservers.push(callback);
 
   return object;
 }
 
 function ObjectUnobserve(object, callback) {
   if (!IS_SPEC_OBJECT(object))
     throw MakeTypeError("observe_non_object", ["unobserve"]);
   if (!IS_SPEC_FUNCTION(callback))
     throw MakeTypeError("observe_non_function", ["unobserve"]);
 
   var objectInfo = objectInfoMap.get(object);
   if (IS_UNDEFINED(objectInfo))
     return object;
 
-  ensureObserverRemoved(objectInfo, callback);
-
-  if (objectInfo.changeObservers.length === 0 &&
-      objectInfo.inactiveObservers.length === 0) {
-    %SetIsObserved(object, false);
+  var changeObservers = objectInfo.changeObservers;
+  var index = changeObservers.indexOf(callback);
+  if (index >= 0) {
+    changeObservers.splice(index, 1);
+    if (changeObservers.length === 0) %SetIsObserved(object, false);
   }
 
   return object;
 }
 
 function EnqueueChangeRecord(changeRecord, observers) {
   // TODO(rossberg): adjust once there is a story for symbols vs proxies.
   if (IS_SYMBOL(changeRecord.name)) return;
 
   for (var i = 0; i < observers.length; i++) {
     var observer = observers[i];
-    if (IS_UNDEFINED(observer.accept[changeRecord.type]))
-      continue;
-
-    var callback = observer.callback;
-    var observerInfo = observerInfoMap.get(callback);
-    observationState.pendingObservers[observerInfo.priority] = callback;
+    var observerInfo = observerInfoMap.get(observer);
+    observationState.pendingObservers[observerInfo.priority] = observer;
     %SetObserverDeliveryPending();
     if (IS_NULL(observerInfo.pendingChangeRecords)) {
       observerInfo.pendingChangeRecords = new InternalArray(changeRecord);
     } else {
       observerInfo.pendingChangeRecords.push(changeRecord);
     }
   }
 }
 
 function NotifyChange(type, object, name, oldValue) {
   var objectInfo = objectInfoMap.get(object);
-  if (objectInfo.changeObservers.length === 0)
-    return;
-
   var changeRecord = (arguments.length < 4) ?
       { type: type, object: object, name: name } :
       { type: type, object: object, name: name, oldValue: oldValue };
   // TODO(rafaelw): This breaks spec-compliance. Re-enable when freezing isn't
   // slow.
   // ObjectFreeze(changeRecord);
   EnqueueChangeRecord(changeRecord, objectInfo.changeObservers);
 }
 
 var notifierPrototype = {};
@@ skipping 18 matching lines @@
     %DefineOrRedefineDataProperty(newRecord, prop, changeRecord[prop],
         READ_ONLY + DONT_DELETE);
   }
   // TODO(rafaelw): This breaks spec-compliance. Re-enable when freezing isn't
   // slow.
   // ObjectFreeze(newRecord);
 
   EnqueueChangeRecord(newRecord, objectInfo.changeObservers);
 }
 
-function ObjectNotifierPerformChange(changeType, changeFn, receiver) {
-  if (!IS_SPEC_OBJECT(this))
-    throw MakeTypeError("called_on_non_object", ["performChange"]);
-
-  var target = notifierTargetMap.get(this);
-  if (IS_UNDEFINED(target))
-    throw MakeTypeError("observe_notify_non_notifier");
-  if (!IS_STRING(changeType))
-    throw MakeTypeError("observe_perform_non_string");
-  if (!IS_SPEC_FUNCTION(changeFn))
-    throw MakeTypeError("observe_perform_non_function");
-
-  if (IS_NULL_OR_UNDEFINED(receiver)) {
-    receiver = %GetDefaultReceiver(changeFn) || receiver;
-  } else if (!IS_SPEC_OBJECT(receiver) && %IsClassicModeFunction(changeFn)) {
-    receiver = ToObject(receiver);
-  }
-
-  var objectInfo = objectInfoMap.get(target);
-  if (IS_UNDEFINED(objectInfo))
-    return;
-
-  BeginPerformChange(objectInfo, changeType);
-  try {
-    %_CallFunction(receiver, changeFn);
-  } finally {
-    EndPerformChange(objectInfo, changeType);
-  }
-}
-
 function ObjectGetNotifier(object) {
   if (!IS_SPEC_OBJECT(object))
     throw MakeTypeError("observe_non_object", ["getNotifier"]);
 
   if (ObjectIsFrozen(object)) return null;
 
   var objectInfo = objectInfoMap.get(object);
   if (IS_UNDEFINED(objectInfo)) objectInfo = CreateObjectInfo(object);
 
   if (IS_NULL(objectInfo.notifier)) {
@@ skipping 42 matching lines @@
 
 function SetupObjectObserve() {
   %CheckIsBootstrapping();
   InstallFunctions($Object, DONT_ENUM, $Array(
     "deliverChangeRecords", ObjectDeliverChangeRecords,
     "getNotifier", ObjectGetNotifier,
     "observe", ObjectObserve,
     "unobserve", ObjectUnobserve
   ));
   InstallFunctions(notifierPrototype, DONT_ENUM, $Array(
-    "notify", ObjectNotifierNotify,
-    "performChange", ObjectNotifierPerformChange
+    "notify", ObjectNotifierNotify
   ));
 }
 
 SetupObjectObserve();