First attempt at providing default traits for PersistentValueMap.

test/cctest/test-api.cc

 // 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 3427 matching lines @@
   {
     v8::UniquePersistent<String> unique = ReturnUnique(isolate, global);
     CHECK(unique == global);
     CHECK_EQ(initial_handle_count + 1, global_handles->global_handles_count());
   }
   CHECK_EQ(initial_handle_count, global_handles->global_handles_count());
   global.Reset();
 }
 
 
-template<typename K, typename V, bool is_weak>
-class StdPersistentValueMapTraits {
+template<typename K, typename V>
+class WeakStdMapTraits : public v8::DefaultPersistentValueMapTraits<K, V> {
  public:
-  static const bool kIsWeak = is_weak;
-  typedef v8::PersistentContainerValue VInt;
-  typedef std::map<K, VInt> Impl;
+  typedef typename v8::DefaultPersistentValueMapTraits<K, V>::Impl Impl;
+  static const bool kIsWeak = true;
   struct WeakCallbackDataType {
     Impl* impl;
     K key;
   };
-  typedef typename Impl::iterator Iterator;
-  static bool Empty(Impl* impl) { return impl->empty(); }
-  static size_t Size(Impl* impl) { return impl->size(); }
-  static void Swap(Impl& a, Impl& b) { std::swap(a, b); }  // NOLINT
-  static Iterator Begin(Impl* impl) { return impl->begin(); }
-  static Iterator End(Impl* impl) { return impl->end(); }
-  static K Key(Iterator it) { return it->first; }
-  static VInt Value(Iterator it) { return it->second; }
-  static VInt Set(Impl* impl, K key, VInt value) {
-    std::pair<Iterator, bool> res = impl->insert(std::make_pair(key, value));
-    VInt old_value = v8::kPersistentContainerNotFound;
-    if (!res.second) {
-      old_value = res.first->second;
-      res.first->second = value;
-    }
-    return old_value;
-  }
-  static VInt Get(Impl* impl, K key) {
-    Iterator it = impl->find(key);
-    if (it == impl->end()) return v8::kPersistentContainerNotFound;
-    return it->second;
-  }
-  static VInt Remove(Impl* impl, K key) {
-    Iterator it = impl->find(key);
-    if (it == impl->end()) return v8::kPersistentContainerNotFound;
-    VInt value = it->second;
-    impl->erase(it);
-    return value;
-  }
-  static void Dispose(v8::Isolate* isolate, v8::UniquePersistent<V> value,
-      Impl* impl, K key) {}
   static WeakCallbackDataType* WeakCallbackParameter(
       Impl* impl, const K& key, Local<V> value) {
     WeakCallbackDataType* data = new WeakCallbackDataType;
     data->impl = impl;
     data->key = key;
     return data;
   }
   static Impl* ImplFromWeakCallbackData(
       const v8::WeakCallbackData<V, WeakCallbackDataType>& data) {
     return data.GetParameter()->impl;
   }
   static K KeyFromWeakCallbackData(
       const v8::WeakCallbackData<V, WeakCallbackDataType>& data) {
     return data.GetParameter()->key;
   }
   static void DisposeCallbackData(WeakCallbackDataType* data) {
     delete data;
   }
 };
 
 
-template<bool is_weak>
+template<typename Map>
 static void TestPersistentValueMap() {
   LocalContext env;
   v8::Isolate* isolate = env->GetIsolate();
-  typedef v8::PersistentValueMap<int, v8::Object,
-      StdPersistentValueMapTraits<int, v8::Object, is_weak> > Map;
   Map map(isolate);
   v8::internal::GlobalHandles* global_handles =
       reinterpret_cast<v8::internal::Isolate*>(isolate)->global_handles();
   int initial_handle_count = global_handles->global_handles_count();
   CHECK_EQ(0, static_cast<int>(map.Size()));
   {
     HandleScope scope(isolate);
     Local<v8::Object> obj = map.Get(7);
     CHECK(obj.IsEmpty());
     Local<v8::Object> expected = v8::Object::New(isolate);
     map.Set(7, expected);
     CHECK_EQ(1, static_cast<int>(map.Size()));
     obj = map.Get(7);
     CHECK_EQ(expected, obj);
     v8::UniquePersistent<v8::Object> removed = map.Remove(7);
     CHECK_EQ(0, static_cast<int>(map.Size()));
     CHECK(expected == removed);
     removed = map.Remove(7);
     CHECK(removed.IsEmpty());
     map.Set(8, expected);
     CHECK_EQ(1, static_cast<int>(map.Size()));
     map.Set(8, expected);
     CHECK_EQ(1, static_cast<int>(map.Size()));
   }
   CHECK_EQ(initial_handle_count + 1, global_handles->global_handles_count());
-  if (is_weak) {
+  if (map.IsWeak()) {
     reinterpret_cast<v8::internal::Isolate*>(isolate)->heap()->
         CollectAllGarbage(i::Heap::kAbortIncrementalMarkingMask);
   } else {
     map.Clear();
   }
   CHECK_EQ(0, static_cast<int>(map.Size()));
   CHECK_EQ(initial_handle_count, global_handles->global_handles_count());
 }
 
 
 TEST(PersistentValueMap) {
-  TestPersistentValueMap<false>();
-  TestPersistentValueMap<true>();
+  // Default case, w/o weak callbacks:
+  TestPersistentValueMap<v8::StdPersistentValueMap<int, v8::Object> >();
+
+  // Custom traits with weak callbacks:
+  typedef v8::StdPersistentValueMap<int, v8::Object,
+      WeakStdMapTraits<int, v8::Object> > WeakPersistentValueMap;
+  TestPersistentValueMap<WeakPersistentValueMap>();
 }
 
 
 THREADED_TEST(GlobalHandleUpcast) {
   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope scope(isolate);
   v8::Local<String> local = v8::Local<String>::New(isolate, v8_str("str"));
   v8::Persistent<String> global_string(isolate, local);
   v8::Persistent<Value>& global_value =
       v8::Persistent<Value>::Cast(global_string);
@@ skipping 18820 matching lines @@
   CompileRun("x1 = x2 = 0;");
   rr = v8::Promise::Resolver::New(isolate);
   rr->GetPromise()->Catch(f1)->Chain(f2);
   rr->Reject(v8::Integer::New(isolate, 3));
   CHECK_EQ(0, global->Get(v8_str("x1"))->Int32Value());
   CHECK_EQ(0, global->Get(v8_str("x2"))->Int32Value());
   V8::RunMicrotasks(isolate);
   CHECK_EQ(3, global->Get(v8_str("x1"))->Int32Value());
   CHECK_EQ(4, global->Get(v8_str("x2"))->Int32Value());
 }