gin: Add the concept of named and indexed interceptors.

gin/interceptor.h

+// Copyright 2014 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_INTERCEPTOR_H_
+#define GIN_INTERCEPTOR_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "gin/gin_export.h"
+#include "v8/include/v8.h"
+
+namespace gin {
+
+class WrappableBase;
+
+// Base class for gin::Wrappable-derived classes that want to implement a
+// property interceptor.
+class GIN_EXPORT NamedPropertyInterceptor {
+ public:
+  NamedPropertyInterceptor(v8::Isolate* isolate, WrappableBase* base);
+  virtual ~NamedPropertyInterceptor();
+
+  virtual v8::Local<v8::Value> GetNamedProperty(v8::Isolate* isolate,
+                                                const std::string& property);
+  virtual void SetNamedProperty(v8::Isolate* isolate,
+                                const std::string& property,
+                                v8::Local<v8::Value> value);
+  virtual std::vector<std::string> EnumerateNamedProperties(
+      v8::Isolate* isolate);
+
+ private:
+  v8::Isolate* isolate_;
+  WrappableBase* base_;
+
+  DISALLOW_COPY_AND_ASSIGN(NamedPropertyInterceptor);
+};
+
+class GIN_EXPORT IndexedPropertyInterceptor {
+ public:
+  IndexedPropertyInterceptor(v8::Isolate* isolate, WrappableBase* base);
+  virtual ~IndexedPropertyInterceptor();
+
+  virtual v8::Local<v8::Value> GetIndexedProperty(v8::Isolate* isolate,
+                                                  uint32_t index);
+  virtual void SetIndexedProperty(v8::Isolate* isolate,
+                                  uint32_t index,
+                                  v8::Local<v8::Value> value);
+  virtual std::vector<uint32_t> EnumerateIndexedProperties(
+      v8::Isolate* isolate);
+
+ private:
+  v8::Isolate* isolate_;
+  WrappableBase* base_;
+
+  DISALLOW_COPY_AND_ASSIGN(IndexedPropertyInterceptor);
+};
+
+}  // namespace gin
+
+#endif  // GIN_INTERCEPTOR_H_