src: remove C++ WeakReference implementation

Author: joyeecheung

node.gyp

@@ -253,7 +253,6 @@
       'src/node_stat_watcher.h',
       'src/node_union_bytes.h',
       'src/node_url.h',
-      'src/node_util.h',
       'src/node_version.h',
       'src/node_v8.h',
       'src/node_v8_platform-inl.h',

src/base_object_types.h

@@ -29,7 +29,6 @@ namespace node {
 // SET_OBJECT_ID(), the second argument should match the C++ class
 // name.
 #define SERIALIZABLE_NON_BINDING_TYPES(V)                                      \
-  V(util_weak_reference, util::WeakReference)
 
 // Helper list of all binding data wrapper types.
 #define BINDING_TYPES(V)                                                       \

src/inspector/node_string.cc

@@ -1,6 +1,5 @@
 #include "node_string.h"
 #include "node/inspector/protocol/Protocol.h"
-#include "node_util.h"
 #include "simdutf.h"
 #include "util-inl.h"
 

src/node_snapshotable.cc

@@ -22,7 +22,6 @@
 #include "node_process.h"
 #include "node_snapshot_builder.h"
 #include "node_url.h"
-#include "node_util.h"
 #include "node_v8.h"
 #include "node_v8_platform-inl.h"
 #include "timers.h"

src/node_util.cc

@@ -1,4 +1,3 @@
-#include "node_util.h"
 #include "base_object-inl.h"
 #include "node_errors.h"
 #include "node_external_reference.h"
@@ -201,109 +200,6 @@ void ArrayBufferViewHasBuffer(const FunctionCallbackInfo<Value>& args) {
   args.GetReturnValue().Set(args[0].As<ArrayBufferView>()->HasBuffer());
 }
 
-WeakReference::WeakReference(Realm* realm,
-                             Local<Object> object,
-                             Local<Object> target)
-    : WeakReference(realm, object, target, 0) {}
-
-WeakReference::WeakReference(Realm* realm,
-                             Local<Object> object,
-                             Local<Object> target,
-                             uint64_t reference_count)
-    : SnapshotableObject(realm, object, type_int),
-      reference_count_(reference_count) {
-  MakeWeak();
-  if (!target.IsEmpty()) {
-    target_.Reset(realm->isolate(), target);
-    if (reference_count_ == 0) {
-      target_.SetWeak();
-    }
-  }
-}
-
-bool WeakReference::PrepareForSerialization(Local<Context> context,
-                                            v8::SnapshotCreator* creator) {
-  if (target_.IsEmpty()) {
-    target_index_ = 0;
-    return true;
-  }
-
-  // Users can still hold strong references to target in addition to the
-  // reference that we manage here, and they could expect that the referenced
-  // object remains the same as long as that external strong reference
-  // is alive. Since we have no way to know if there is any other reference
-  // keeping the target alive, the best we can do to maintain consistency is to
-  // simply save a reference to the target in the snapshot (effectively making
-  // it strong) during serialization, and restore it during deserialization.
-  // If there's no known counted reference from our side, we'll make the
-  // reference here weak upon deserialization so that it can be GC'ed if users
-  // do not hold additional references to it.
-  Local<Object> target = target_.Get(context->GetIsolate());
-  target_index_ = creator->AddData(context, target);
-  DCHECK_NE(target_index_, 0);
-  target_.Reset();
-  return true;
-}
-
-InternalFieldInfoBase* WeakReference::Serialize(int index) {
-  DCHECK_EQ(index, BaseObject::kEmbedderType);
-  InternalFieldInfo* info =
-      InternalFieldInfoBase::New<InternalFieldInfo>(type());
-  info->target = target_index_;
-  info->reference_count = reference_count_;
-  return info;
-}
-
-void WeakReference::Deserialize(Local<Context> context,
-                                Local<Object> holder,
-                                int index,
-                                InternalFieldInfoBase* info) {
-  DCHECK_EQ(index, BaseObject::kEmbedderType);
-  HandleScope scope(context->GetIsolate());
-
-  InternalFieldInfo* weak_info = reinterpret_cast<InternalFieldInfo*>(info);
-  Local<Object> target;
-  if (weak_info->target != 0) {
-    target = context->GetDataFromSnapshotOnce<Object>(weak_info->target)
-                 .ToLocalChecked();
-  }
-  new WeakReference(
-      Realm::GetCurrent(context), holder, target, weak_info->reference_count);
-}
-
-void WeakReference::New(const FunctionCallbackInfo<Value>& args) {
-  Realm* realm = Realm::GetCurrent(args);
-  CHECK(args.IsConstructCall());
-  CHECK(args[0]->IsObject());
-  new WeakReference(realm, args.This(), args[0].As<Object>());
-}
-
-void WeakReference::Get(const FunctionCallbackInfo<Value>& args) {
-  WeakReference* weak_ref = Unwrap<WeakReference>(args.Holder());
-  Isolate* isolate = args.GetIsolate();
-  if (!weak_ref->target_.IsEmpty())
-    args.GetReturnValue().Set(weak_ref->target_.Get(isolate));
-}
-
-void WeakReference::IncRef(const FunctionCallbackInfo<Value>& args) {
-  WeakReference* weak_ref = Unwrap<WeakReference>(args.Holder());
-  weak_ref->reference_count_++;
-  if (weak_ref->target_.IsEmpty()) return;
-  if (weak_ref->reference_count_ == 1) weak_ref->target_.ClearWeak();
-  args.GetReturnValue().Set(
-      v8::Number::New(args.GetIsolate(), weak_ref->reference_count_));
-}
-
-void WeakReference::DecRef(const FunctionCallbackInfo<Value>& args) {
-  WeakReference* weak_ref = Unwrap<WeakReference>(args.Holder());
-  CHECK_GE(weak_ref->reference_count_, 1);
-  weak_ref->reference_count_--;
-  if (weak_ref->target_.IsEmpty()) return;
-  if (weak_ref->reference_count_ == 0) weak_ref->target_.SetWeak();
-  args.GetReturnValue().Set(
-      v8::Number::New(args.GetIsolate(), weak_ref->reference_count_));
-}
-
 static uint32_t GetUVHandleTypeCode(const uv_handle_type type) {
   // TODO(anonrig): We can use an enum here and then create the array in the
   // binding, which will remove the hard-coding in C++ and JS land.
@@ -391,10 +287,6 @@ void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
   registry->Register(GetExternalValue);
   registry->Register(Sleep);
   registry->Register(ArrayBufferViewHasBuffer);
-  registry->Register(WeakReference::New);
-  registry->Register(WeakReference::Get);
-  registry->Register(WeakReference::IncRef);
-  registry->Register(WeakReference::DecRef);
   registry->Register(GuessHandleType);
   registry->Register(FastGuessHandleType);
   registry->Register(fast_guess_handle_type_.GetTypeInfo());
@@ -508,15 +400,6 @@ void Initialize(Local<Object> target,
                   env->should_abort_on_uncaught_toggle().GetJSArray())
             .FromJust());
 
-  Local<FunctionTemplate> weak_ref =
-      NewFunctionTemplate(isolate, WeakReference::New);
-  weak_ref->InstanceTemplate()->SetInternalFieldCount(
-      WeakReference::kInternalFieldCount);
-  SetProtoMethod(isolate, weak_ref, "get", WeakReference::Get);
-  SetProtoMethod(isolate, weak_ref, "incRef", WeakReference::IncRef);
-  SetProtoMethod(isolate, weak_ref, "decRef", WeakReference::DecRef);
-  SetConstructorFunction(context, target, "WeakReference", weak_ref);
-
   SetFastMethodNoSideEffect(context,
                             target,
                             "guessHandleType",

src/node_util.h

@@ -27,7 +27,6 @@
 #include "node_buffer.h"
 #include "node_errors.h"
 #include "node_internals.h"
-#include "node_util.h"
 #include "node_v8_platform-inl.h"
 #include "string_bytes.h"
 #include "uv.h"