Initial commit.

native_mate/object_template_builder.h

@@ -0,0 +1,123 @@
+// 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_OBJECT_TEMPLATE_BUILDER_H_
+#define NATIVE_MATE_OBJECT_TEMPLATE_BUILDER_H_
+
+#include "base/bind.h"
+#include "base/callback.h"
+#include "base/strings/string_piece.h"
+#include "base/template_util.h"
+#include "native_mate/converter.h"
+#include "native_mate/function_template.h"
+#include "v8/include/v8.h"
+
+namespace mate {
+
+namespace {
+
+// Base template - used only for non-member function pointers. Other types
+// either go to one of the below specializations, or go here and fail to compile
+// because of base::Bind().
+template<typename T, typename Enable = void>
+struct CallbackTraits {
+  static v8::Handle<v8::FunctionTemplate> CreateTemplate(v8::Isolate* isolate,
+                                                         T callback) {
+    return CreateFunctionTemplate(isolate, base::Bind(callback));
+  }
+};
+
+// Specialization for base::Callback.
+template<typename T>
+struct CallbackTraits<base::Callback<T> > {
+  static v8::Handle<v8::FunctionTemplate> CreateTemplate(
+      v8::Isolate* isolate, const base::Callback<T>& callback) {
+    return CreateFunctionTemplate(isolate, callback);
+  }
+};
+
+// Specialization for member function pointers. We need to handle this case
+// specially because the first parameter for callbacks to MFP should typically
+// come from the the JavaScript "this" object the function was called on, not
+// from the first normal parameter.
+template<typename T>
+struct CallbackTraits<T, typename base::enable_if<
+                           base::is_member_function_pointer<T>::value>::type> {
+  static v8::Handle<v8::FunctionTemplate> CreateTemplate(v8::Isolate* isolate,
+                                                         T callback) {
+    return CreateFunctionTemplate(isolate, base::Bind(callback),
+                                  HolderIsFirstArgument);
+  }
+};
+
+// This specialization allows people to construct function templates directly if
+// they need to do fancier stuff.
+template<>
+struct CallbackTraits<v8::Handle<v8::FunctionTemplate> > {
+  static v8::Handle<v8::FunctionTemplate> CreateTemplate(
+      v8::Handle<v8::FunctionTemplate> templ) {
+    return templ;
+  }
+};
+
+}  // namespace
+
+
+// ObjectTemplateBuilder provides a handy interface to creating
+// v8::ObjectTemplate instances with various sorts of properties.
+class ObjectTemplateBuilder {
+ public:
+  explicit ObjectTemplateBuilder(v8::Isolate* isolate);
+  ~ObjectTemplateBuilder();
+
+  // It's against Google C++ style to return a non-const ref, but we take some
+  // poetic license here in order that all calls to Set() can be via the '.'
+  // operator and line up nicely.
+  template<typename T>
+  ObjectTemplateBuilder& SetValue(const base::StringPiece& name, T val) {
+    return SetImpl(name, ConvertToV8(isolate_, val));
+  }
+
+  // In the following methods, T and U can be function pointer, member function
+  // pointer, base::Callback, or v8::FunctionTemplate. Most clients will want to
+  // use one of the first two options. Also see mate::CreateFunctionTemplate()
+  // for creating raw function templates.
+  template<typename T>
+  ObjectTemplateBuilder& SetMethod(const base::StringPiece& name,
+                                   const T& callback) {
+    return SetImpl(name, CallbackTraits<T>::CreateTemplate(isolate_, callback));
+  }
+  template<typename T>
+  ObjectTemplateBuilder& SetProperty(const base::StringPiece& name,
+                                     const T& getter) {
+    return SetPropertyImpl(name,
+                           CallbackTraits<T>::CreateTemplate(isolate_, getter),
+                           v8::Local<v8::FunctionTemplate>());
+  }
+  template<typename T, typename U>
+  ObjectTemplateBuilder& SetProperty(const base::StringPiece& name,
+                                     const T& getter, const U& setter) {
+    return SetPropertyImpl(name,
+                           CallbackTraits<T>::CreateTemplate(isolate_, getter),
+                           CallbackTraits<U>::CreateTemplate(isolate_, setter));
+  }
+
+  v8::Local<v8::ObjectTemplate> Build();
+
+ private:
+  ObjectTemplateBuilder& SetImpl(const base::StringPiece& name,
+                                 v8::Handle<v8::Data> val);
+  ObjectTemplateBuilder& SetPropertyImpl(
+      const base::StringPiece& name, v8::Handle<v8::FunctionTemplate> getter,
+      v8::Handle<v8::FunctionTemplate> setter);
+
+  v8::Isolate* isolate_;
+
+  // ObjectTemplateBuilder should only be used on the stack.
+  v8::Local<v8::ObjectTemplate> template_;
+};
+
+}  // namespace mate
+
+#endif  // NATIVE_MATE_OBJECT_TEMPLATE_BUILDER_H_