src: avoid prototype access in binding templates

This patch makes the binding templates ObjectTemplates, since we
don't actually need the constructor function. This also avoids
setting the properties on prototype, and instead initializes them
directly on the object template.

Previously the initialization was similar to:

```
function Binding() {}
Binding.prototype.property = ...;
module.exports = new Binding;
```

Now it's similar to:

```
module.exports = { property: ... };
```

PR-URL: nodejs#47913
Reviewed-By: Chengzhong Wu <[email protected]>
Reviewed-By: James M Snell <[email protected]>

Author: joyeecheung

src/async_wrap.cc

@@ -353,9 +353,8 @@ Local<FunctionTemplate> AsyncWrap::GetConstructorTemplate(
 }
 
 void AsyncWrap::CreatePerIsolateProperties(IsolateData* isolate_data,
-                                           Local<FunctionTemplate> ctor) {
+                                           Local<ObjectTemplate> target) {
   Isolate* isolate = isolate_data->isolate();
-  Local<ObjectTemplate> target = ctor->InstanceTemplate();
 
   SetMethod(isolate, target, "setupHooks", SetupHooks);
   SetMethod(isolate, target, "setCallbackTrampoline", SetCallbackTrampoline);

src/async_wrap.h

@@ -151,8 +151,8 @@ class AsyncWrap : public BaseObject {
                                          v8::Local<v8::Value> unused,
                                          v8::Local<v8::Context> context,
                                          void* priv);
-  static void CreatePerIsolateProperties(
-      IsolateData* isolate_data, v8::Local<v8::FunctionTemplate> target);
+  static void CreatePerIsolateProperties(IsolateData* isolate_data,
+                                         v8::Local<v8::ObjectTemplate> target);
 
   static void GetAsyncId(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void PushAsyncContext(const v8::FunctionCallbackInfo<v8::Value>& args);

src/encoding_binding.cc

@@ -16,7 +16,6 @@ using v8::ArrayBuffer;
 using v8::BackingStore;
 using v8::Context;
 using v8::FunctionCallbackInfo;
-using v8::FunctionTemplate;
 using v8::Isolate;
 using v8::Local;
 using v8::MaybeLocal;
@@ -219,9 +218,8 @@ void BindingData::ToUnicode(const v8::FunctionCallbackInfo<v8::Value>& args) {
 }
 
 void BindingData::CreatePerIsolateProperties(IsolateData* isolate_data,
-                                             Local<FunctionTemplate> ctor) {
+                                             Local<ObjectTemplate> target) {
   Isolate* isolate = isolate_data->isolate();
-  Local<ObjectTemplate> target = ctor->InstanceTemplate();
   SetMethod(isolate, target, "encodeInto", EncodeInto);
   SetMethodNoSideEffect(isolate, target, "encodeUtf8String", EncodeUtf8String);
   SetMethodNoSideEffect(isolate, target, "decodeUTF8", DecodeUTF8);

src/encoding_binding.h

@@ -36,7 +36,7 @@ class BindingData : public SnapshotableObject {
   static void ToUnicode(const v8::FunctionCallbackInfo<v8::Value>& args);
 
   static void CreatePerIsolateProperties(IsolateData* isolate_data,
-                                         v8::Local<v8::FunctionTemplate> ctor);
+                                         v8::Local<v8::ObjectTemplate> target);
   static void CreatePerContextProperties(v8::Local<v8::Object> target,
                                          v8::Local<v8::Value> unused,
                                          v8::Local<v8::Context> context,

src/env-inl.h

@@ -807,7 +807,7 @@ void Environment::set_process_exit_handler(
 #undef VY
 #undef VP
 
-#define VM(PropertyName) V(PropertyName##_binding, v8::FunctionTemplate)
+#define VM(PropertyName) V(PropertyName##_binding_template, v8::ObjectTemplate)
 #define V(PropertyName, TypeName)                                              \
   inline v8::Local<TypeName> IsolateData::PropertyName() const {               \
     return PropertyName##_.Get(isolate_);                                      \

src/env.cc

@@ -38,7 +38,6 @@ using v8::Context;
 using v8::EmbedderGraph;
 using v8::EscapableHandleScope;
 using v8::Function;
-using v8::FunctionTemplate;
 using v8::HandleScope;
 using v8::HeapProfiler;
 using v8::HeapSpaceStatistics;
@@ -49,6 +48,7 @@ using v8::MaybeLocal;
 using v8::NewStringType;
 using v8::Number;
 using v8::Object;
+using v8::ObjectTemplate;
 using v8::Private;
 using v8::Script;
 using v8::SnapshotCreator;
@@ -326,7 +326,7 @@ IsolateDataSerializeInfo IsolateData::Serialize(SnapshotCreator* creator) {
     info.primitive_values.push_back(creator->AddData(async_wrap_provider(i)));
 
   uint32_t id = 0;
-#define VM(PropertyName) V(PropertyName##_binding, FunctionTemplate)
+#define VM(PropertyName) V(PropertyName##_binding_template, ObjectTemplate)
 #define V(PropertyName, TypeName)                                              \
   do {                                                                         \
     Local<TypeName> field = PropertyName();                                    \
@@ -390,7 +390,7 @@ void IsolateData::DeserializeProperties(const IsolateDataSerializeInfo* info) {
   const std::vector<PropInfo>& values = info->template_values;
   i = 0;  // index to the array
   uint32_t id = 0;
-#define VM(PropertyName) V(PropertyName##_binding, FunctionTemplate)
+#define VM(PropertyName) V(PropertyName##_binding_template, ObjectTemplate)
 #define V(PropertyName, TypeName)                                              \
   do {                                                                         \
     if (values.size() > i && id == values[i].id) {                             \
@@ -491,10 +491,9 @@ void IsolateData::CreateProperties() {
   NODE_ASYNC_PROVIDER_TYPES(V)
 #undef V
 
-  Local<FunctionTemplate> templ = FunctionTemplate::New(isolate());
-  templ->InstanceTemplate()->SetInternalFieldCount(
-      BaseObject::kInternalFieldCount);
-  set_binding_data_ctor_template(templ);
+  Local<ObjectTemplate> templ = ObjectTemplate::New(isolate());
+  templ->SetInternalFieldCount(BaseObject::kInternalFieldCount);
+  set_binding_data_default_template(templ);
   binding::CreateInternalBindingTemplates(this);
 
   contextify::ContextifyContext::InitializeGlobalTemplates(this);

src/env.h

@@ -166,7 +166,7 @@ class NODE_EXTERN_PRIVATE IsolateData : public MemoryRetainer {
 #undef VS
 #undef VP
 
-#define VM(PropertyName) V(PropertyName##_binding, v8::FunctionTemplate)
+#define VM(PropertyName) V(PropertyName##_binding_template, v8::ObjectTemplate)
 #define V(PropertyName, TypeName)                                              \
   inline v8::Local<TypeName> PropertyName() const;                             \
   inline void set_##PropertyName(v8::Local<TypeName> value);
@@ -194,7 +194,7 @@ class NODE_EXTERN_PRIVATE IsolateData : public MemoryRetainer {
 #define VY(PropertyName, StringValue) V(v8::Symbol, PropertyName)
 #define VS(PropertyName, StringValue) V(v8::String, PropertyName)
 #define VR(PropertyName, TypeName) V(v8::Private, per_realm_##PropertyName)
-#define VM(PropertyName) V(v8::FunctionTemplate, PropertyName##_binding)
+#define VM(PropertyName) V(v8::ObjectTemplate, PropertyName##_binding_template)
 #define VT(PropertyName, TypeName) V(TypeName, PropertyName)
 #define V(TypeName, PropertyName)                                             \
   v8::Eternal<TypeName> PropertyName ## _;

src/env_properties.h

@@ -333,7 +333,7 @@
 #define PER_ISOLATE_TEMPLATE_PROPERTIES(V)                                     \
   V(async_wrap_ctor_template, v8::FunctionTemplate)                            \
   V(async_wrap_object_ctor_template, v8::FunctionTemplate)                     \
-  V(binding_data_ctor_template, v8::FunctionTemplate)                          \
+  V(binding_data_default_template, v8::ObjectTemplate)                         \
   V(blob_constructor_template, v8::FunctionTemplate)                           \
   V(blob_reader_constructor_template, v8::FunctionTemplate)                    \
   V(blocklist_constructor_template, v8::FunctionTemplate)                      \

src/node_binding.cc

@@ -101,7 +101,7 @@ NODE_BUILTIN_BINDINGS(V)
 
 #define V(modname)                                                             \
   void _register_isolate_##modname(node::IsolateData* isolate_data,            \
-                                   v8::Local<v8::FunctionTemplate> target);
+                                   v8::Local<v8::ObjectTemplate> target);
 NODE_BINDINGS_WITH_PER_ISOLATE_INIT(V)
 #undef V
 
@@ -235,11 +235,11 @@ using v8::Context;
 using v8::EscapableHandleScope;
 using v8::Exception;
 using v8::FunctionCallbackInfo;
-using v8::FunctionTemplate;
 using v8::HandleScope;
 using v8::Isolate;
 using v8::Local;
 using v8::Object;
+using v8::ObjectTemplate;
 using v8::String;
 using v8::Value;
 
@@ -572,12 +572,11 @@ inline struct node_module* FindModule(struct node_module* list,
 void CreateInternalBindingTemplates(IsolateData* isolate_data) {
 #define V(modname)                                                             \
   do {                                                                         \
-    Local<FunctionTemplate> templ =                                            \
-        FunctionTemplate::New(isolate_data->isolate());                        \
-    templ->InstanceTemplate()->SetInternalFieldCount(                          \
-        BaseObject::kInternalFieldCount);                                      \
+    Local<ObjectTemplate> templ =                                              \
+        ObjectTemplate::New(isolate_data->isolate());                          \
+    templ->SetInternalFieldCount(BaseObject::kInternalFieldCount);             \
     _register_isolate_##modname(isolate_data, templ);                          \
-    isolate_data->set_##modname##_binding(templ);                              \
+    isolate_data->set_##modname##_binding_template(templ);                     \
   } while (0);
   NODE_BINDINGS_WITH_PER_ISOLATE_INIT(V)
 #undef V
@@ -586,21 +585,20 @@ void CreateInternalBindingTemplates(IsolateData* isolate_data) {
 static Local<Object> GetInternalBindingExportObject(IsolateData* isolate_data,
                                                     const char* mod_name,
                                                     Local<Context> context) {
-  Local<FunctionTemplate> ctor;
+  Local<ObjectTemplate> templ;
+
 #define V(name)                                                                \
   if (strcmp(mod_name, #name) == 0) {                                          \
-    ctor = isolate_data->name##_binding();                                     \
+    templ = isolate_data->name##_binding_template();                           \
   } else  // NOLINT(readability/braces)
   NODE_BINDINGS_WITH_PER_ISOLATE_INIT(V)
 #undef V
   {
-    ctor = isolate_data->binding_data_ctor_template();
+    // Default template.
+    templ = isolate_data->binding_data_default_template();
   }
 
-  Local<Object> obj = ctor->GetFunction(context)
-                          .ToLocalChecked()
-                          ->NewInstance(context)
-                          .ToLocalChecked();
+  Local<Object> obj = templ->NewInstance(context).ToLocalChecked();
   return obj;
 }
 

src/node_binding.h

@@ -84,7 +84,7 @@ namespace node {
 // list.
 #define NODE_BINDING_PER_ISOLATE_INIT(modname, per_isolate_func)               \
   void _register_isolate_##modname(node::IsolateData* isolate_data,            \
-                                   v8::Local<v8::FunctionTemplate> target) {   \
+                                   v8::Local<v8::ObjectTemplate> target) {     \
     per_isolate_func(isolate_data, target);                                    \
   }