electron/native_mate/native_mate/converter.h
Charles Kerr f6fb877de9
chore: pass base::StringPiece args by value (#19432)
https://cs.chromium.org/chromium/src/base/strings/string_piece.h?l=14
discusses this, saying "Prefer passing StringPieces by value" because
"[p]assing by value generates slightly smaller code."
2019-07-25 10:19:04 -05:00

351 lines
11 KiB
C++

// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE.chromium file.
#ifndef NATIVE_MATE_NATIVE_MATE_CONVERTER_H_
#define NATIVE_MATE_NATIVE_MATE_CONVERTER_H_
#include <map>
#include <set>
#include <string>
#include <type_traits>
#include <utility>
#include <vector>
#include "base/strings/string_piece.h"
#include "gin/converter.h"
#include "v8/include/v8.h"
namespace mate {
template <typename KeyType>
bool SetProperty(v8::Isolate* isolate,
v8::Local<v8::Object> object,
KeyType key,
v8::Local<v8::Value> value) {
auto maybe = object->Set(isolate->GetCurrentContext(), key, value);
return !maybe.IsNothing() && maybe.FromJust();
}
template <typename T>
struct ToV8ReturnsMaybe {
static const bool value = false;
};
template <typename T, typename Enable = void>
struct Converter {};
template <>
struct Converter<void*> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, void* val) {
return v8::Undefined(isolate);
}
};
template <>
struct Converter<std::nullptr_t> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, std::nullptr_t val) {
return v8::Null(isolate);
}
};
template <>
struct Converter<bool> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, bool val);
static bool FromV8(v8::Isolate* isolate, v8::Local<v8::Value> val, bool* out);
};
#if !defined(OS_LINUX) && !defined(OS_FREEBSD)
template <>
struct Converter<unsigned long> { // NOLINT(runtime/int)
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
unsigned long val); // NOLINT(runtime/int)
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
unsigned long* out); // NOLINT(runtime/int)
};
#endif
template <>
struct Converter<int32_t> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, int32_t val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
int32_t* out);
};
template <>
struct Converter<uint32_t> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, uint32_t val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
uint32_t* out);
};
template <>
struct Converter<int64_t> {
// Warning: JavaScript cannot represent 64 integers precisely.
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, int64_t val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
int64_t* out);
};
template <>
struct Converter<uint64_t> {
// Warning: JavaScript cannot represent 64 integers precisely.
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, uint64_t val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
uint64_t* out);
};
template <>
struct Converter<float> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, float val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
float* out);
};
template <>
struct Converter<double> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, double val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
double* out);
};
template <>
struct Converter<const char*> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, const char* val);
};
template <>
struct Converter<base::StringPiece> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, base::StringPiece val);
// No conversion out is possible because StringPiece does not contain storage.
};
template <>
struct Converter<std::string> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
const std::string& val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
std::string* out);
};
v8::Local<v8::String> StringToSymbol(v8::Isolate* isolate,
base::StringPiece input);
template <>
struct Converter<v8::Local<v8::Function>> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
v8::Local<v8::Function> val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
v8::Local<v8::Function>* out);
};
template <>
struct Converter<v8::Local<v8::Object>> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
v8::Local<v8::Object> val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
v8::Local<v8::Object>* out);
};
template <>
struct Converter<v8::Local<v8::String>> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
v8::Local<v8::String> val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
v8::Local<v8::String>* out);
};
template <>
struct Converter<v8::Local<v8::External>> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
v8::Local<v8::External> val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
v8::Local<v8::External>* out);
};
template <>
struct Converter<v8::Local<v8::Array>> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
v8::Local<v8::Array> val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
v8::Local<v8::Array>* out);
};
template <>
struct Converter<v8::Local<v8::Value>> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
v8::Local<v8::Value> val);
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
v8::Local<v8::Value>* out);
};
template <>
struct Converter<v8::Local<v8::Promise>> {
static v8::Local<v8::Promise> ToV8(v8::Isolate* isolate,
v8::Local<v8::Promise> val);
// static bool FromV8(v8::Isolate* isolate,
// v8::Local<v8::Value> val,
// v8::Local<v8::Value>* out);
};
template <typename T>
struct Converter<std::vector<T>> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
const std::vector<T>& val) {
v8::Local<v8::Array> result(
v8::Array::New(isolate, static_cast<int>(val.size())));
auto context = isolate->GetCurrentContext();
for (size_t i = 0; i < val.size(); ++i) {
result
->Set(context, static_cast<int>(i),
Converter<T>::ToV8(isolate, val[i]))
.Check();
}
return result;
}
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
std::vector<T>* out) {
if (!val->IsArray())
return false;
auto context = isolate->GetCurrentContext();
std::vector<T> result;
v8::Local<v8::Array> array(v8::Local<v8::Array>::Cast(val));
uint32_t length = array->Length();
for (uint32_t i = 0; i < length; ++i) {
T item;
if (!Converter<T>::FromV8(isolate,
array->Get(context, i).ToLocalChecked(), &item))
return false;
result.push_back(item);
}
out->swap(result);
return true;
}
};
template <typename T>
struct Converter<std::set<T>> {
static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
const std::set<T>& val) {
v8::Local<v8::Array> result(
v8::Array::New(isolate, static_cast<int>(val.size())));
auto context = isolate->GetCurrentContext();
typename std::set<T>::const_iterator it;
int i;
for (i = 0, it = val.begin(); it != val.end(); ++it, ++i)
result->Set(context, i, Converter<T>::ToV8(isolate, *it)).Check();
return result;
}
static bool FromV8(v8::Isolate* isolate,
v8::Local<v8::Value> val,
std::set<T>* out) {
if (!val->IsArray())
return false;
auto context = isolate->GetCurrentContext();
std::set<T> result;
v8::Local<v8::Array> array(v8::Local<v8::Array>::Cast(val));
uint32_t length = array->Length();
for (uint32_t i = 0; i < length; ++i) {
T item;
if (!Converter<T>::FromV8(isolate,
array->Get(context, i).ToLocalChecked(), &item))
return false;
result.insert(item);
}
out->swap(result);
return true;
}
};
// Convenience functions that deduce T.
template <typename T>
v8::Local<v8::Value> ConvertToV8(v8::Isolate* isolate, const T& input) {
return Converter<T>::ToV8(isolate, input);
}
template <typename T>
v8::Local<v8::Value> ConvertToV8(v8::Isolate* isolate, T&& input) {
return Converter<typename std::remove_reference<T>::type>::ToV8(
isolate, std::move(input));
}
inline v8::Local<v8::Value> ConvertToV8(v8::Isolate* isolate,
const char* input) {
return Converter<const char*>::ToV8(isolate, input);
}
template <typename T>
v8::MaybeLocal<v8::Value> ConvertToV8(v8::Local<v8::Context> context,
const T& input) {
return Converter<T>::ToV8(context, input);
}
template <typename T, bool = ToV8ReturnsMaybe<T>::value>
struct ToV8Traits;
template <typename T>
struct ToV8Traits<T, true> {
static bool TryConvertToV8(v8::Isolate* isolate,
const T& input,
v8::Local<v8::Value>* output) {
auto maybe = ConvertToV8(isolate->GetCurrentContext(), input);
if (maybe.IsEmpty())
return false;
*output = maybe.ToLocalChecked();
return true;
}
};
template <typename T>
struct ToV8Traits<T, false> {
static bool TryConvertToV8(v8::Isolate* isolate,
const T& input,
v8::Local<v8::Value>* output) {
*output = ConvertToV8(isolate, input);
return true;
}
};
template <typename T>
bool TryConvertToV8(v8::Isolate* isolate,
const T& input,
v8::Local<v8::Value>* output) {
return ToV8Traits<T>::TryConvertToV8(isolate, input, output);
}
template <typename T>
bool ConvertFromV8(v8::Isolate* isolate,
v8::Local<v8::Value> input,
T* result) {
return Converter<T>::FromV8(isolate, input, result);
}
inline v8::Local<v8::String> StringToV8(v8::Isolate* isolate,
base::StringPiece input) {
return ConvertToV8(isolate, input).As<v8::String>();
}
} // namespace mate
#endif // NATIVE_MATE_NATIVE_MATE_CONVERTER_H_