/******************************************************************************

* Experimental prototype for demonstrating VM agnostic and ABI stable API

* for native modules to use instead of using Nan and V8 APIs directly.

*

* The current status is "Experimental" and should not be used for

* production applications. The API is still subject to change

* and as an experimental feature is NOT subject to semver.

*

******************************************************************************/

#include <node_buffer.h>

#include <node_object_wrap.h>

#include <string.h>

#include <algorithm>

#include <cmath>

#include <vector>

#include "node_api.h"

#include "env-inl.h"

static

napi_status napi_set_last_error(napi_env env, napi_status error_code,

uint32_t engine_error_code = 0,

void* engine_reserved = nullptr);

static

void napi_clear_last_error(napi_env env);

struct napi_env__ {

explicit napi_env__(v8::Isolate* _isolate): isolate(_isolate),

has_instance_available(true), last_error() {}

~napi_env__() {

last_exception.Reset();

has_instance.Reset();

}

v8::Isolate* isolate;

v8::Persistent<v8::Value> last_exception;

v8::Persistent<v8::Value> has_instance;

bool has_instance_available;

napi_extended_error_info last_error;

};

#define RETURN_STATUS_IF_FALSE(env, condition, status) \

do { \

if (!(condition)) { \

return napi_set_last_error((env), (status)); \

} \

} while (0)

#define CHECK_ENV(env) \

if ((env) == nullptr) { \

node::FatalError(__func__, "environment(env) must not be null"); \

}

#define CHECK_ARG(env, arg) \

RETURN_STATUS_IF_FALSE((env), ((arg) != nullptr), napi_invalid_arg)

#define CHECK_MAYBE_EMPTY(env, maybe, status) \

RETURN_STATUS_IF_FALSE((env), !((maybe).IsEmpty()), (status))

#define CHECK_MAYBE_NOTHING(env, maybe, status) \

RETURN_STATUS_IF_FALSE((env), !((maybe).IsNothing()), (status))

// NAPI_PREAMBLE is not wrapped in do..while: try_catch must have function scope

#define NAPI_PREAMBLE(env) \

CHECK_ENV((env)); \

RETURN_STATUS_IF_FALSE((env), (env)->last_exception.IsEmpty(), \

napi_pending_exception); \

napi_clear_last_error((env)); \

v8impl::TryCatch try_catch((env))

#define CHECK_TO_TYPE(env, type, context, result, src, status) \

do { \

auto maybe = v8impl::V8LocalValueFromJsValue((src))->To##type((context)); \

CHECK_MAYBE_EMPTY((env), maybe, (status)); \

(result) = maybe.ToLocalChecked(); \

} while (0)

#define CHECK_TO_OBJECT(env, context, result, src) \

CHECK_TO_TYPE((env), Object, (context), (result), (src), napi_object_expected)

#define CHECK_TO_STRING(env, context, result, src) \

CHECK_TO_TYPE((env), String, (context), (result), (src), napi_string_expected)

#define CHECK_TO_NUMBER(env, context, result, src) \

CHECK_TO_TYPE((env), Number, (context), (result), (src), napi_number_expected)

#define CHECK_TO_BOOL(env, context, result, src) \

CHECK_TO_TYPE((env), Boolean, (context), (result), (src), \

napi_boolean_expected)

#define CHECK_NEW_FROM_UTF8_LEN(env, result, str, len) \

do { \

auto str_maybe = v8::String::NewFromUtf8( \

(env)->isolate, (str), v8::NewStringType::kInternalized, (len)); \

CHECK_MAYBE_EMPTY((env), str_maybe, napi_generic_failure); \

(result) = str_maybe.ToLocalChecked(); \

} while (0)

#define CHECK_NEW_FROM_UTF8(env, result, str) \

CHECK_NEW_FROM_UTF8_LEN((env), (result), (str), -1)

#define GET_RETURN_STATUS(env) \

(!try_catch.HasCaught() ? napi_ok \

: napi_set_last_error((env), napi_pending_exception))

namespace {

namespace v8impl {

// convert from n-api property attributes to v8::PropertyAttribute

static inline v8::PropertyAttribute V8PropertyAttributesFromDescriptor(

const napi_property_descriptor* descriptor) {

unsigned int attribute_flags = v8::PropertyAttribute::None;

if (descriptor->getter != nullptr || descriptor->setter != nullptr) {

// The napi_writable attribute is ignored for accessor descriptors, but

// V8 requires the ReadOnly attribute to match nonexistence of a setter.

attribute_flags |= (descriptor->setter == nullptr ?

v8::PropertyAttribute::ReadOnly : v8::PropertyAttribute::None);

} else if ((descriptor->attributes & napi_writable) == 0) {

attribute_flags |= v8::PropertyAttribute::ReadOnly;

}

if ((descriptor->attributes & napi_enumerable) == 0) {

attribute_flags |= v8::PropertyAttribute::DontEnum;

}

if ((descriptor->attributes & napi_configurable) == 0) {

attribute_flags |= v8::PropertyAttribute::DontDelete;

}

return static_cast<v8::PropertyAttribute>(attribute_flags);

}

class HandleScopeWrapper {

public:

explicit HandleScopeWrapper(v8::Isolate* isolate) : scope(isolate) {}

private:

v8::HandleScope scope;

};

// In node v0.10 version of v8, there is no EscapableHandleScope and the

// node v0.10 port use HandleScope::Close(Local<T> v) to mimic the behavior

// of a EscapableHandleScope::Escape(Local<T> v), but it is not the same

// semantics. This is an example of where the api abstraction fail to work

// across different versions.

class EscapableHandleScopeWrapper {

public:

explicit EscapableHandleScopeWrapper(v8::Isolate* isolate) : scope(isolate) {}

template <typename T>

v8::Local<T> Escape(v8::Local<T> handle) {

return scope.Escape(handle);

}

private:

v8::EscapableHandleScope scope;

};

napi_handle_scope JsHandleScopeFromV8HandleScope(HandleScopeWrapper* s) {

return reinterpret_cast<napi_handle_scope>(s);

}

HandleScopeWrapper* V8HandleScopeFromJsHandleScope(napi_handle_scope s) {

return reinterpret_cast<HandleScopeWrapper*>(s);

}

napi_escapable_handle_scope JsEscapableHandleScopeFromV8EscapableHandleScope(

EscapableHandleScopeWrapper* s) {

return reinterpret_cast<napi_escapable_handle_scope>(s);

}

EscapableHandleScopeWrapper*

V8EscapableHandleScopeFromJsEscapableHandleScope(

napi_escapable_handle_scope s) {

return reinterpret_cast<EscapableHandleScopeWrapper*>(s);

}

//=== Conversion between V8 Handles and napi_value ========================

// This asserts v8::Local<> will always be implemented with a single

// pointer field so that we can pass it around as a void*.

static_assert(sizeof(v8::Local<v8::Value>) == sizeof(napi_value),

"Cannot convert between v8::Local<v8::Value> and napi_value");

napi_value JsValueFromV8LocalValue(v8::Local<v8::Value> local) {

return reinterpret_cast<napi_value>(*local);

}

v8::Local<v8::Value> V8LocalValueFromJsValue(napi_value v) {

v8::Local<v8::Value> local;

memcpy(&local, &v, sizeof(v));

return local;

}

static inline napi_status V8NameFromPropertyDescriptor(napi_env env,

const napi_property_descriptor* p,

v8::Local<v8::Name>* result) {

if (p->utf8name != nullptr) {

CHECK_NEW_FROM_UTF8(env, *result, p->utf8name);

} else {

v8::Local<v8::Value> property_value =

v8impl::V8LocalValueFromJsValue(p->name);

RETURN_STATUS_IF_FALSE(env, property_value->IsName(), napi_name_expected);

*result = property_value.As<v8::Name>();

}

return napi_ok;

}

// Adapter for napi_finalize callbacks.

class Finalizer {

protected:

Finalizer(napi_env env,

napi_finalize finalize_callback,

void* finalize_data,

void* finalize_hint)

: _env(env),

_finalize_callback(finalize_callback),

_finalize_data(finalize_data),

_finalize_hint(finalize_hint) {

}

~Finalizer() {

}

public:

static Finalizer* New(napi_env env,

napi_finalize finalize_callback = nullptr,

void* finalize_data = nullptr,

void* finalize_hint = nullptr) {

return new Finalizer(

env, finalize_callback, finalize_data, finalize_hint);

}

static void Delete(Finalizer* finalizer) {

delete finalizer;

}

// node::Buffer::FreeCallback

static void FinalizeBufferCallback(char* data, void* hint) {

Finalizer* finalizer = static_cast<Finalizer*>(hint);

if (finalizer->_finalize_callback != nullptr) {

finalizer->_finalize_callback(

finalizer->_env,

data,

finalizer->_finalize_hint);

}

Delete(finalizer);

}

protected:

napi_env _env;

napi_finalize _finalize_callback;

void* _finalize_data;

void* _finalize_hint;

};

// Wrapper around v8::Persistent that implements reference counting.

class Reference : private Finalizer {

private:

Reference(napi_env env,

v8::Local<v8::Value> value,

uint32_t initial_refcount,

bool delete_self,

napi_finalize finalize_callback,

void* finalize_data,

void* finalize_hint)

: Finalizer(env, finalize_callback, finalize_data, finalize_hint),

_persistent(env->isolate, value),

_refcount(initial_refcount),

_delete_self(delete_self) {

if (initial_refcount == 0) {

_persistent.SetWeak(

this, FinalizeCallback, v8::WeakCallbackType::kParameter);

_persistent.MarkIndependent();

}

}

~Reference() {

// The V8 Persistent class currently does not reset in its destructor:

// see NonCopyablePersistentTraits::kResetInDestructor = false.

// (Comments there claim that might change in the future.)

// To avoid memory leaks, it is better to reset at this time, however

// care must be taken to avoid attempting this after the Isolate has

// shut down, for example via a static (atexit) destructor.

_persistent.Reset();

}

public:

static Reference* New(napi_env env,

v8::Local<v8::Value> value,

uint32_t initial_refcount,

bool delete_self,

napi_finalize finalize_callback = nullptr,

void* finalize_data = nullptr,

void* finalize_hint = nullptr) {

return new Reference(env,

value,

initial_refcount,

delete_self,

finalize_callback,

finalize_data,

finalize_hint);

}

static void Delete(Reference* reference) {

delete reference;

}

uint32_t Ref() {

if (++_refcount == 1) {

_persistent.ClearWeak();

}

return _refcount;

}

uint32_t Unref() {

if (_refcount == 0) {

return 0;

}

if (--_refcount == 0) {

_persistent.SetWeak(

this, FinalizeCallback, v8::WeakCallbackType::kParameter);

_persistent.MarkIndependent();

}

return _refcount;

}

uint32_t RefCount() {

return _refcount;

}

v8::Local<v8::Value> Get() {

if (_persistent.IsEmpty()) {

return v8::Local<v8::Value>();

} else {

return v8::Local<v8::Value>::New(_env->isolate, _persistent);

}

}

private:

static void FinalizeCallback(const v8::WeakCallbackInfo<Reference>& data) {

Reference* reference = data.GetParameter();

reference->_persistent.Reset();

// Check before calling the finalize callback, because the callback might

// delete it.

bool delete_self = reference->_delete_self;

if (reference->_finalize_callback != nullptr) {

reference->_finalize_callback(

reference->_env,

reference->_finalize_data,

reference->_finalize_hint);

}

if (delete_self) {

Delete(reference);

}

}

v8::Persistent<v8::Value> _persistent;

uint32_t _refcount;

bool _delete_self;

};

class TryCatch : public v8::TryCatch {

public:

explicit TryCatch(napi_env env)

: v8::TryCatch(env->isolate), _env(env) {}

~TryCatch() {

if (HasCaught()) {

_env->last_exception.Reset(_env->isolate, Exception());

}

}

private:

napi_env _env;

};

//=== Function napi_callback wrapper =================================

static const int kDataIndex = 0;

static const int kEnvIndex = 1;

static const int kFunctionIndex = 2;

static const int kFunctionFieldCount = 3;

static const int kGetterIndex = 2;

static const int kSetterIndex = 3;

static const int kAccessorFieldCount = 4;

// Base class extended by classes that wrap V8 function and property callback

// info.

class CallbackWrapper {

public:

CallbackWrapper(napi_value this_arg, size_t args_length, void* data)

: _this(this_arg), _args_length(args_length), _data(data) {}

virtual bool IsConstructCall() = 0;

virtual void Args(napi_value* buffer, size_t bufferlength) = 0;

virtual void SetReturnValue(napi_value value) = 0;

napi_value This() { return _this; }

size_t ArgsLength() { return _args_length; }

void* Data() { return _data; }

protected:

const napi_value _this;

const size_t _args_length;

void* _data;

};

template <typename Info, int kInternalFieldIndex>

class CallbackWrapperBase : public CallbackWrapper {

public:

CallbackWrapperBase(const Info& cbinfo, const size_t args_length)

: CallbackWrapper(JsValueFromV8LocalValue(cbinfo.This()),

args_length,

nullptr),

_cbinfo(cbinfo),

_cbdata(v8::Local<v8::Object>::Cast(cbinfo.Data())) {

_data = v8::Local<v8::External>::Cast(_cbdata->GetInternalField(kDataIndex))

->Value();

}

/*virtual*/

bool IsConstructCall() override { return false; }

protected:

void InvokeCallback() {

napi_callback_info cbinfo_wrapper = reinterpret_cast<napi_callback_info>(

static_cast<CallbackWrapper*>(this));

napi_callback cb = reinterpret_cast<napi_callback>(

v8::Local<v8::External>::Cast(

_cbdata->GetInternalField(kInternalFieldIndex))->Value());

v8::Isolate* isolate = _cbinfo.GetIsolate();

napi_env env = static_cast<napi_env>(

v8::Local<v8::External>::Cast(

_cbdata->GetInternalField(kEnvIndex))->Value());

// Make sure any errors encountered last time we were in N-API are gone.

napi_clear_last_error(env);

napi_value result = cb(env, cbinfo_wrapper);

if (result != nullptr) {

this->SetReturnValue(result);

}

if (!env->last_exception.IsEmpty()) {

isolate->ThrowException(

v8::Local<v8::Value>::New(isolate, env->last_exception));

env->last_exception.Reset();

}

}

const Info& _cbinfo;

const v8::Local<v8::Object> _cbdata;

};

class FunctionCallbackWrapper

: public CallbackWrapperBase<v8::FunctionCallbackInfo<v8::Value>,

kFunctionIndex> {

public:

static void Invoke(const v8::FunctionCallbackInfo<v8::Value>& info) {

FunctionCallbackWrapper cbwrapper(info);

cbwrapper.InvokeCallback();

}

explicit FunctionCallbackWrapper(

const v8::FunctionCallbackInfo<v8::Value>& cbinfo)

: CallbackWrapperBase(cbinfo, cbinfo.Length()) {}

/*virtual*/

bool IsConstructCall() override { return _cbinfo.IsConstructCall(); }

/*virtual*/

void Args(napi_value* buffer, size_t buffer_length) override {

size_t i = 0;

size_t min = std::min(buffer_length, _args_length);

for (; i < min; i += 1) {

buffer[i] = v8impl::JsValueFromV8LocalValue(_cbinfo[i]);

}

if (i < buffer_length) {

napi_value undefined =

v8impl::JsValueFromV8LocalValue(v8::Undefined(_cbinfo.GetIsolate()));

for (; i < buffer_length; i += 1) {

buffer[i] = undefined;

}

}

}

/*virtual*/

void SetReturnValue(napi_value value) override {

v8::Local<v8::Value> val = v8impl::V8LocalValueFromJsValue(value);

_cbinfo.GetReturnValue().Set(val);

}

};

class GetterCallbackWrapper

: public CallbackWrapperBase<v8::PropertyCallbackInfo<v8::Value>,

kGetterIndex> {

public:

static void Invoke(v8::Local<v8::Name> property,

const v8::PropertyCallbackInfo<v8::Value>& info) {

GetterCallbackWrapper cbwrapper(info);

cbwrapper.InvokeCallback();

}

explicit GetterCallbackWrapper(

const v8::PropertyCallbackInfo<v8::Value>& cbinfo)

: CallbackWrapperBase(cbinfo, 0) {}

/*virtual*/

void Args(napi_value* buffer, size_t buffer_length) override {

if (buffer_length > 0) {

napi_value undefined =

v8impl::JsValueFromV8LocalValue(v8::Undefined(_cbinfo.GetIsolate()));

for (size_t i = 0; i < buffer_length; i += 1) {

buffer[i] = undefined;

}

}

}

/*virtual*/

void SetReturnValue(napi_value value) override {

v8::Local<v8::Value> val = v8impl::V8LocalValueFromJsValue(value);

_cbinfo.GetReturnValue().Set(val);

}

};

class SetterCallbackWrapper

: public CallbackWrapperBase<v8::PropertyCallbackInfo<void>, kSetterIndex> {

public:

static void Invoke(v8::Local<v8::Name> property,

v8::Local<v8::Value> value,

const v8::PropertyCallbackInfo<void>& info) {

SetterCallbackWrapper cbwrapper(info, value);

cbwrapper.InvokeCallback();

}

SetterCallbackWrapper(const v8::PropertyCallbackInfo<void>& cbinfo,

const v8::Local<v8::Value>& value)

: CallbackWrapperBase(cbinfo, 1), _value(value) {}

/*virtual*/

void Args(napi_value* buffer, size_t buffer_length) override {

if (buffer_length > 0) {

buffer[0] = v8impl::JsValueFromV8LocalValue(_value);

if (buffer_length > 1) {

napi_value undefined = v8impl::JsValueFromV8LocalValue(

v8::Undefined(_cbinfo.GetIsolate()));

for (size_t i = 1; i < buffer_length; i += 1) {

buffer[i] = undefined;

}

}

}

}

/*virtual*/

void SetReturnValue(napi_value value) override {

node::FatalError("napi_set_return_value",

"Cannot return a value from a setter callback.");

}

private:

const v8::Local<v8::Value>& _value;

};

// Creates an object to be made available to the static function callback

// wrapper, used to retrieve the native callback function and data pointer.

v8::Local<v8::Object> CreateFunctionCallbackData(napi_env env,

napi_callback cb,

void* data) {

v8::Isolate* isolate = env->isolate;

v8::Local<v8::Context> context = isolate->GetCurrentContext();

v8::Local<v8::ObjectTemplate> otpl = v8::ObjectTemplate::New(isolate);

otpl->SetInternalFieldCount(v8impl::kFunctionFieldCount);

v8::Local<v8::Object> cbdata = otpl->NewInstance(context).ToLocalChecked();

cbdata->SetInternalField(

v8impl::kEnvIndex,

v8::External::New(isolate, static_cast<void*>(env)));

cbdata->SetInternalField(

v8impl::kFunctionIndex,

v8::External::New(isolate, reinterpret_cast<void*>(cb)));

cbdata->SetInternalField(

v8impl::kDataIndex,

v8::External::New(isolate, data));

return cbdata;

}

// Creates an object to be made available to the static getter/setter

// callback wrapper, used to retrieve the native getter/setter callback

// function and data pointer.

v8::Local<v8::Object> CreateAccessorCallbackData(napi_env env,

napi_callback getter,

napi_callback setter,

void* data) {

v8::Isolate* isolate = env->isolate;

v8::Local<v8::Context> context = isolate->GetCurrentContext();

v8::Local<v8::ObjectTemplate> otpl = v8::ObjectTemplate::New(isolate);

otpl->SetInternalFieldCount(v8impl::kAccessorFieldCount);

v8::Local<v8::Object> cbdata = otpl->NewInstance(context).ToLocalChecked();

cbdata->SetInternalField(

v8impl::kEnvIndex,

v8::External::New(isolate, static_cast<void*>(env)));

if (getter != nullptr) {

cbdata->SetInternalField(

v8impl::kGetterIndex,

v8::External::New(isolate, reinterpret_cast<void*>(getter)));

}

if (setter != nullptr) {

cbdata->SetInternalField(

v8impl::kSetterIndex,

v8::External::New(isolate, reinterpret_cast<void*>(setter)));

}

cbdata->SetInternalField(

v8impl::kDataIndex,

v8::External::New(isolate, data));

return cbdata;

}

} // end of namespace v8impl

// Intercepts the Node-V8 module registration callback. Converts parameters

// to NAPI equivalents and then calls the registration callback specified

// by the NAPI module.

void napi_module_register_cb(v8::Local<v8::Object> exports,

v8::Local<v8::Value> module,

v8::Local<v8::Context> context,

void* priv) {

napi_module* mod = static_cast<napi_module*>(priv);

// Create a new napi_env for this module. Once module unloading is supported

// we shall have to call delete on this object from there.

napi_env env = new napi_env__(context->GetIsolate());

mod->nm_register_func(

env,

v8impl::JsValueFromV8LocalValue(exports),

v8impl::JsValueFromV8LocalValue(module),

mod->nm_priv);

}

} // end of anonymous namespace

#ifndef EXTERNAL_NAPI

namespace node {

// Indicates whether NAPI was enabled/disabled via the node command-line.

extern bool load_napi_modules;

}

#endif // EXTERNAL_NAPI

// Registers a NAPI module.

void napi_module_register(napi_module* mod) {

// NAPI modules always work with the current node version.

int module_version = NODE_MODULE_VERSION;

#ifndef EXTERNAL_NAPI

if (!node::load_napi_modules) {

// NAPI is disabled, so set the module version to -1 to cause the module

// to be unloaded.

module_version = -1;

}

#endif // EXTERNAL_NAPI

node::node_module* nm = new node::node_module {

module_version,

mod->nm_flags,

nullptr,

mod->nm_filename,

nullptr,

napi_module_register_cb,

mod->nm_modname,

mod, // priv

nullptr,

};

node::node_module_register(nm);

}

// Warning: Keep in-sync with napi_status enum

const char* error_messages[] = {nullptr,

"Invalid pointer passed as argument",

"An object was expected",

"A string was expected",

"A string or symbol was expected",

"A function was expected",

"A number was expected",

"A boolean was expected",

"An array was expected",

"Unknown failure",

"An exception is pending",

"The async work item was cancelled"};

void napi_clear_last_error(napi_env env) {

env->last_error.error_code = napi_ok;

// TODO(boingoing): Should this be a callback?

env->last_error.engine_error_code = 0;

env->last_error.engine_reserved = nullptr;

}

napi_status napi_set_last_error(napi_env env, napi_status error_code,

uint32_t engine_error_code,

void* engine_reserved) {

env->last_error.error_code = error_code;

env->last_error.engine_error_code = engine_error_code;

env->last_error.engine_reserved = engine_reserved;

return error_code;

}

napi_status napi_get_last_error_info(napi_env env,

const napi_extended_error_info** result) {

CHECK_ENV(env);

static_assert(node::arraysize(error_messages) == napi_status_last,

"Count of error messages must match count of error values");

assert(env->last_error.error_code < napi_status_last);

// Wait until someone requests the last error information to fetch the error

// message string

env->last_error.error_message =

error_messages[env->last_error.error_code];

*result = &(env->last_error);

return napi_ok;

}

napi_status napi_create_function(napi_env env,

const char* utf8name,

napi_callback cb,

void* callback_data,

napi_value* result) {

NAPI_PREAMBLE(env);

CHECK_ARG(env, result);

v8::Isolate* isolate = env->isolate;

v8::Local<v8::Function> return_value;

v8::EscapableHandleScope scope(isolate);

v8::Local<v8::Object> cbdata =

v8impl::CreateFunctionCallbackData(env, cb, callback_data);

RETURN_STATUS_IF_FALSE(env, !cbdata.IsEmpty(), napi_generic_failure);

v8::Local<v8::FunctionTemplate> tpl = v8::FunctionTemplate::New(

isolate, v8impl::FunctionCallbackWrapper::Invoke, cbdata);

v8::Local<v8::Context> context = isolate->GetCurrentContext();

v8::MaybeLocal<v8::Function> maybe_function = tpl->GetFunction(context);

CHECK_MAYBE_EMPTY(env, maybe_function, napi_generic_failure);

return_value = scope.Escape(maybe_function.ToLocalChecked());

if (utf8name != nullptr) {

v8::Local<v8::String> name_string;

CHECK_NEW_FROM_UTF8(env, name_string, utf8name);

return_value->SetName(name_string);

}

*result = v8impl::JsValueFromV8LocalValue(return_value);

return GET_RETURN_STATUS(env);

}

napi_status napi_define_class(napi_env env,

const char* utf8name,

napi_callback constructor,

void* callback_data,

size_t property_count,

const napi_property_descriptor* properties,

napi_value* result) {

NAPI_PREAMBLE(env);

CHECK_ARG(env, result);

v8::Isolate* isolate = env->isolate;

v8::EscapableHandleScope scope(isolate);

v8::Local<v8::Object> cbdata =

v8impl::CreateFunctionCallbackData(env, constructor, callback_data);

RETURN_STATUS_IF_FALSE(env, !cbdata.IsEmpty(), napi_generic_failure);

v8::Local<v8::FunctionTemplate> tpl = v8::FunctionTemplate::New(

isolate, v8impl::FunctionCallbackWrapper::Invoke, cbdata);

// we need an internal field to stash the wrapped object

tpl->InstanceTemplate()->SetInternalFieldCount(1);

v8::Local<v8::String> name_string;

CHECK_NEW_FROM_UTF8(env, name_string, utf8name);

tpl->SetClassName(name_string);

size_t static_property_count = 0;

for (size_t i = 0; i < property_count; i++) {

const napi_property_descriptor* p = properties + i;

if ((p->attributes & napi_static) != 0) {

// Static properties are handled separately below.

static_property_count++;

continue;

}

v8::Local<v8::Name> property_name;

napi_status status =

v8impl::V8NameFromPropertyDescriptor(env, p, &property_name);

if (status != napi_ok) {

return napi_set_last_error(env, status);

}

v8::PropertyAttribute attributes =

v8impl::V8PropertyAttributesFromDescriptor(p);

// This code is similar to that in napi_define_properties(); the

// difference is it applies to a template instead of an object.

if (p->getter != nullptr || p->setter != nullptr) {

v8::Local<v8::Object> cbdata = v8impl::CreateAccessorCallbackData(

env, p->getter, p->setter, p->data);

tpl->PrototypeTemplate()->SetAccessor(

property_name,

p->getter ? v8impl::GetterCallbackWrapper::Invoke : nullptr,

p->setter ? v8impl::SetterCallbackWrapper::Invoke : nullptr,

cbdata,

v8::AccessControl::DEFAULT,

attributes);

} else if (p->method != nullptr) {

v8::Local<v8::Object> cbdata =

v8impl::CreateFunctionCallbackData(env, p->method, p->data);

RETURN_STATUS_IF_FALSE(env, !cbdata.IsEmpty(), napi_generic_failure);

v8::Local<v8::FunctionTemplate> t =

v8::FunctionTemplate::New(isolate,

v8impl::FunctionCallbackWrapper::Invoke,

cbdata,

v8::Signature::New(isolate, tpl));

tpl->PrototypeTemplate()->Set(property_name, t, attributes);

} else {

v8::Local<v8::Value> value = v8impl::V8LocalValueFromJsValue(p->value);

tpl->PrototypeTemplate()->Set(property_name, value, attributes);

}

}

*result = v8impl::JsValueFromV8LocalValue(scope.Escape(tpl->GetFunction()));

if (static_property_count > 0) {

std::vector<napi_property_descriptor> static_descriptors;

static_descriptors.reserve(static_property_count);

for (size_t i = 0; i < property_count; i++) {

const napi_property_descriptor* p = properties + i;

if ((p->attributes & napi_static) != 0) {

static_descriptors.push_back(*p);

}

}

napi_status status =

napi_define_properties(env,

*result,

static_descriptors.size(),

static_descriptors.data());

if (status != napi_ok) return status;

}

return GET_RETURN_STATUS(env);

}

napi_status napi_get_property_names(napi_env env,

napi_value object,

napi_value* result) {

NAPI_PREAMBLE(env);

CHECK_ARG(env, result);

v8::Isolate* isolate = env->isolate;

v8::Local<v8::Context> context = isolate->GetCurrentContext();

v8::Local<v8::Object> obj;

CHECK_TO_OBJECT(env, context, obj, object);

auto maybe_propertynames = obj->GetPropertyNames(context);

CHECK_MAYBE_EMPTY(env, maybe_propertynames, napi_generic_failure);

*result = v8impl::JsValueFromV8LocalValue(

maybe_propertynames.ToLocalChecked());

return GET_RETURN_STATUS(env);

}

napi_status napi_set_property(napi_env env,

napi_value object,

napi_value key,

napi_value value) {

NAPI_PREAMBLE(env);

v8::Isolate* isolate = env->isolate;

v8::Local<v8::Context> context = isolate->GetCurrentContext();

v8::Local<v8::Object> obj;

CHECK_TO_OBJECT(env, context, obj, object);

v8::Local<v8::Value> k = v8impl::V8LocalValueFromJsValue(key);

v8::Local<v8::Value> val = v8impl::V8LocalValueFromJsValue(value);

v8::Maybe<bool> set_maybe = obj->Set(context, k, val);

RETURN_STATUS_IF_FALSE(env, set_maybe.FromMaybe(false), napi_generic_failure);

return GET_RETURN_STATUS(env);

}

napi_status napi_has_property(napi_env env,

napi_value object,

napi_value key,

bool* result) {

NAPI_PREAMBLE(env);

CHECK_ARG(env, result);

v8::Isolate* isolate = env->isolate;

v8::Local<v8::Context> context = isolate->GetCurrentContext();

v8::Local<v8::Object> obj;

CHECK_TO_OBJECT(env, context, obj, object);

v8::Local<v8::Value> k = v8impl::V8LocalValueFromJsValue(key);

v8::Maybe<bool> has_maybe = obj->Has(context, k);

CHECK_MAYBE_NOTHING(env, has_maybe, napi_generic_failure);

*result = has_maybe.FromMaybe(false);

return GET_RETURN_STATUS(env);

}

napi_status napi_get_property(napi_env env,

napi_value object,

napi_value key,

napi_value* result) {

NAPI_PREAMBLE(env);

CHECK_ARG(env, result);

v8::Isolate* isolate = env->isolate;

v8::Local<v8::Context> context = isolate->GetCurrentContext();

v8::Local<v8::Value> k = v8impl::V8LocalValueFromJsValue(key);

v8::Local<v8::Object> obj;

CHECK_TO_OBJECT(env, context, obj, object);

auto get_maybe = obj->Get(context, k);

CHECK_MAYBE_EMPTY(env, get_maybe, napi_generic_failure);

v8::Local<v8::Value> val = get_maybe.ToLocalChecked();

*result = v8impl::JsValueFromV8LocalValue(val);

return GET_RETURN_STATUS(env);

}

napi_status napi_set_named_property(napi_env env,

napi_value object,

const char* utf8name,

napi_value value) {

NAPI_PREAMBLE(env);

v8::Isolate* isolate = env->isolate;

v8::Local<v8::Context> context = isolate->GetCurrentContext();

v8::Local<v8::Object> obj;

CHECK_TO_OBJECT(env, context, obj, object);

v8::Local<v8::Name> key;

CHECK_NEW_FROM_UTF8(env, key, utf8name);

v8::Local<v8::Value> val = v8impl::V8LocalValueFromJsValue(value);

v8::Maybe<bool> set_maybe = obj->Set(context, key, val);

RETURN_STATUS_IF_FALSE(env, set_maybe.FromMaybe(false), napi_generic_failure);

return GET_RETURN_STATUS(env);

}

napi_status napi_has_named_property(napi_env env,

napi_value object,

const char* utf8name,

bool* result) {