gin: Add the concept of named and indexed interceptors.

This will allow for using gin as a drop-in replacement for NPObject.

BUG=347565
R=abarth@chromium.org,dcarney@chromium.org,aa@chromium.org

Review URL: https://codereview.chromium.org/194603003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256431 0039d316-1c4b-4281-b951-d872f2087c98

gin/gin.gyp

@@ -35,6 +35,8 @@
         'function_template.h',
         'gin_export.h',
         'handle.h',
+        'interceptor.cc',
+        'interceptor.h',
         'isolate_holder.cc',
         'modules/console.cc',
         'modules/console.h',
@@ -117,6 +119,7 @@
       ],
       'sources': [
         'converter_unittest.cc',
+        'interceptor_unittest.cc',
         'modules/module_registry_unittest.cc',
         'modules/timer_unittest.cc',
         'per_context_data_unittest.cc',

gin/interceptor.cc

@@ -0,0 +1,64 @@
+// 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.
+
+#include "gin/interceptor.h"
+
+#include <map>
+
+#include "gin/per_isolate_data.h"
+
+namespace gin {
+
+NamedPropertyInterceptor::NamedPropertyInterceptor(v8::Isolate* isolate,
+                                                   WrappableBase* base)
+    : isolate_(isolate), base_(base) {
+  PerIsolateData::From(isolate_)->SetNamedPropertyInterceptor(base_, this);
+}
+
+NamedPropertyInterceptor::~NamedPropertyInterceptor() {
+  PerIsolateData::From(isolate_)->ClearNamedPropertyInterceptor(base_, this);
+}
+
+v8::Local<v8::Value> NamedPropertyInterceptor::GetNamedProperty(
+    v8::Isolate* isolate,
+    const std::string& property) {
+  return v8::Local<v8::Value>();
+}
+
+void NamedPropertyInterceptor::SetNamedProperty(v8::Isolate* isolate,
+                                                const std::string& property,
+                                                v8::Local<v8::Value> value) {}
+
+std::vector<std::string> NamedPropertyInterceptor::EnumerateNamedProperties(
+    v8::Isolate* isolate) {
+  return std::vector<std::string>();
+}
+
+IndexedPropertyInterceptor::IndexedPropertyInterceptor(v8::Isolate* isolate,
+                                                       WrappableBase* base)
+    : isolate_(isolate), base_(base) {
+  PerIsolateData::From(isolate_)->SetIndexedPropertyInterceptor(base_, this);
+}
+
+IndexedPropertyInterceptor::~IndexedPropertyInterceptor() {
+  PerIsolateData::From(isolate_)->ClearIndexedPropertyInterceptor(base_, this);
+}
+
+v8::Local<v8::Value> IndexedPropertyInterceptor::GetIndexedProperty(
+    v8::Isolate* isolate,
+    uint32_t index) {
+  return v8::Local<v8::Value>();
+}
+
+void IndexedPropertyInterceptor::SetIndexedProperty(
+    v8::Isolate* isolate,
+    uint32_t index,
+    v8::Local<v8::Value> value) {}
+
+std::vector<uint32_t> IndexedPropertyInterceptor::EnumerateIndexedProperties(
+    v8::Isolate* isolate) {
+  return std::vector<uint32_t>();
+}
+
+}  // namespace gin

gin/interceptor.h

@@ -0,0 +1,63 @@
+// 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_

gin/interceptor_unittest.cc

@@ -0,0 +1,159 @@
+// 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.
+
+#include "base/logging.h"
+#include "gin/arguments.h"
+#include "gin/handle.h"
+#include "gin/interceptor.h"
+#include "gin/object_template_builder.h"
+#include "gin/per_isolate_data.h"
+#include "gin/public/isolate_holder.h"
+#include "gin/test/v8_test.h"
+#include "gin/try_catch.h"
+#include "gin/wrappable.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace gin {
+
+class MyInterceptor : public Wrappable<MyInterceptor>,
+                      public NamedPropertyInterceptor,
+                      public IndexedPropertyInterceptor {
+ public:
+  static WrapperInfo kWrapperInfo;
+
+  static gin::Handle<MyInterceptor> Create(v8::Isolate* isolate) {
+    return CreateHandle(isolate, new MyInterceptor(isolate));
+  }
+
+  int value() const { return value_; }
+  void set_value(int value) { value_ = value; }
+
+  // gin::NamedPropertyInterceptor
+  virtual v8::Local<v8::Value> GetNamedProperty(v8::Isolate* isolate,
+                                                const std::string& property)
+      OVERRIDE {
+    if (property == "value") {
+      return ConvertToV8(isolate, value_);
+    } else if (property == "func") {
+      return CreateFunctionTemplate(isolate,
+                                    base::Bind(&MyInterceptor::Call),
+                                    HolderIsFirstArgument)->GetFunction();
+    } else {
+      return v8::Local<v8::Value>();
+    }
+  }
+  virtual void SetNamedProperty(v8::Isolate* isolate,
+                                const std::string& property,
+                                v8::Local<v8::Value> value) OVERRIDE {
+    if (property != "value")
+      return;
+    ConvertFromV8(isolate, value, &value_);
+  }
+  virtual std::vector<std::string> EnumerateNamedProperties(
+      v8::Isolate* isolate) OVERRIDE {
+    std::vector<std::string> result;
+    result.push_back("func");
+    result.push_back("value");
+    return result;
+  }
+
+  // gin::IndexedPropertyInterceptor
+  virtual v8::Local<v8::Value> GetIndexedProperty(v8::Isolate* isolate,
+                                                  uint32_t index) OVERRIDE {
+    if (index == 0)
+      return ConvertToV8(isolate, value_);
+    return v8::Local<v8::Value>();
+  }
+  virtual void SetIndexedProperty(v8::Isolate* isolate,
+                                  uint32_t index,
+                                  v8::Local<v8::Value> value) OVERRIDE {
+    if (index != 0)
+      return;
+    ConvertFromV8(isolate, value, &value_);
+  }
+  virtual std::vector<uint32_t> EnumerateIndexedProperties(v8::Isolate* isolate)
+      OVERRIDE {
+    std::vector<uint32_t> result;
+    result.push_back(0);
+    return result;
+  }
+
+ private:
+  explicit MyInterceptor(v8::Isolate* isolate)
+      : NamedPropertyInterceptor(isolate, this),
+        IndexedPropertyInterceptor(isolate, this),
+        value_(0) {}
+  virtual ~MyInterceptor() {}
+
+  // gin::Wrappable
+  virtual ObjectTemplateBuilder GetObjectTemplateBuilder(v8::Isolate* isolate)
+      OVERRIDE {
+    return Wrappable<MyInterceptor>::GetObjectTemplateBuilder(isolate)
+        .AddNamedPropertyInterceptor()
+        .AddIndexedPropertyInterceptor();
+  }
+
+  int Call(int value) {
+    int tmp = value_;
+    value_ = value;
+    return tmp;
+  }
+
+  int value_;
+};
+
+WrapperInfo MyInterceptor::kWrapperInfo = {kEmbedderNativeGin};
+
+class InterceptorTest : public V8Test {
+ public:
+  void RunInterceptorTest(const std::string& script_source) {
+    v8::Isolate* isolate = instance_->isolate();
+    v8::HandleScope handle_scope(isolate);
+
+    gin::Handle<MyInterceptor> obj = MyInterceptor::Create(isolate);
+
+    obj->set_value(42);
+    EXPECT_EQ(42, obj->value());
+
+    v8::Handle<v8::String> source = StringToV8(isolate, script_source);
+    EXPECT_FALSE(source.IsEmpty());
+
+    gin::TryCatch try_catch;
+    v8::Handle<v8::Script> script = v8::Script::Compile(source);
+    EXPECT_FALSE(script.IsEmpty());
+    v8::Handle<v8::Value> val = script->Run();
+    EXPECT_FALSE(val.IsEmpty());
+    v8::Handle<v8::Function> func;
+    EXPECT_TRUE(ConvertFromV8(isolate, val, &func));
+    v8::Handle<v8::Value> argv[] = {ConvertToV8(isolate, obj.get()), };
+    func->Call(v8::Undefined(isolate), 1, argv);
+    EXPECT_FALSE(try_catch.HasCaught());
+    EXPECT_EQ("", try_catch.GetStackTrace());
+
+    EXPECT_EQ(191, obj->value());
+  }
+};
+
+TEST_F(InterceptorTest, NamedInterceptor) {
+  RunInterceptorTest(
+      "(function (obj) {"
+      "   if (obj.value !== 42) throw 'FAIL';"
+      "   else obj.value = 191; })");
+}
+
+TEST_F(InterceptorTest, NamedInterceptorCall) {
+  RunInterceptorTest(
+      "(function (obj) {"
+      "   if (obj.func(191) !== 42) throw 'FAIL';"
+      "   })");
+}
+
+TEST_F(InterceptorTest, IndexedInterceptor) {
+  RunInterceptorTest(
+      "(function (obj) {"
+      "   if (obj[0] !== 42) throw 'FAIL';"
+      "   else obj[0] = 191; })");
+}
+
+}  // namespace gin