| // Copyright 2017 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 file. |
| |
| #ifndef GIN_DATA_OBJECT_BUILDER_H_ |
| #define GIN_DATA_OBJECT_BUILDER_H_ |
| |
| #include <utility> |
| |
| #include "base/check.h" |
| #include "base/macros.h" |
| #include "base/strings/string_piece.h" |
| #include "gin/converter.h" |
| #include "gin/gin_export.h" |
| #include "v8/include/v8.h" |
| |
| namespace gin { |
| |
| // Constructs a JavaScript object with a series of data properties. |
| // (As with default data properties in JavaScript, these properties are |
| // configurable, writable and enumerable.) |
| // |
| // Values are automatically converted using gin::Converter, though if |
| // using a type where the conversion may fail, callers must convert ahead of |
| // time. |
| // |
| // This class avoids the pitfall of using v8::Object::Set, which may invoke |
| // setters on the object prototype. |
| // |
| // Expected usage: |
| // v8::Local<v8::Object> object = gin::DataObjectBuilder(isolate) |
| // .Set("boolean", true) |
| // .Set("integer", 42) |
| // .Build(); |
| // |
| // Because this builder class contains local handles, callers must ensure it |
| // does not outlive the scope in which it is created. |
| class GIN_EXPORT DataObjectBuilder { |
| public: |
| explicit DataObjectBuilder(v8::Isolate* isolate); |
| |
| template <typename T> |
| DataObjectBuilder& Set(base::StringPiece key, T&& value) { |
| DCHECK(!object_.IsEmpty()); |
| v8::Local<v8::String> v8_key = StringToSymbol(isolate_, key); |
| v8::Local<v8::Value> v8_value = |
| ConvertToV8(isolate_, std::forward<T>(value)); |
| CHECK(object_->CreateDataProperty(context_, v8_key, v8_value).ToChecked()); |
| return *this; |
| } |
| |
| template <typename T> |
| DataObjectBuilder& Set(uint32_t index, T&& value) { |
| DCHECK(!object_.IsEmpty()); |
| v8::Local<v8::Value> v8_value = |
| ConvertToV8(isolate_, std::forward<T>(value)); |
| CHECK(object_->CreateDataProperty(context_, index, v8_value).ToChecked()); |
| return *this; |
| } |
| |
| v8::Local<v8::Object> Build() { |
| DCHECK(!object_.IsEmpty()); |
| v8::Local<v8::Object> result = object_; |
| object_.Clear(); |
| return result; |
| } |
| |
| private: |
| v8::Isolate* isolate_; |
| v8::Local<v8::Context> context_; |
| v8::Local<v8::Object> object_; |
| |
| DISALLOW_COPY_AND_ASSIGN(DataObjectBuilder); |
| }; |
| |
| } // namespace gin |
| |
| #endif // GIN_DATA_OBJECT_BUILDER_H_ |