Lazy load chrome.* APIs

chrome/renderer/extensions/module_system.cc

 // Copyright (c) 2012 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 "chrome/renderer/extensions/module_system.h"
 
 #include "base/bind.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebScopedMicrotaskSuppression.h"
 
 namespace {
@@ skipping 85 matching lines @@
       stack_trace.assign(*stack_value, stack_value.length());
     else
       stack_trace = "<could not convert stack trace to string>";
   }
 
   LOG(ERROR) << "[" << resource_name << "(" << message->GetLineNumber() << ")] "
              << error_message
              << "{" << stack_trace << "}";
 }
 
-void ModuleSystem::Require(const std::string& module_name) {
+v8::Handle<v8::Value> ModuleSystem::Require(const std::string& module_name) {
   v8::HandleScope handle_scope;
-  RequireForJsInner(v8::String::New(module_name.c_str()));
+  return handle_scope.Close(
+      RequireForJsInner(v8::String::New(module_name.c_str())));
 }
 
 v8::Handle<v8::Value> ModuleSystem::RequireForJs(const v8::Arguments& args) {
   v8::HandleScope handle_scope;
   v8::Handle<v8::String> module_name = args[0]->ToString();
   return handle_scope.Close(RequireForJsInner(module_name));
 }
 
 v8::Handle<v8::Value> ModuleSystem::RequireForJsInner(
     v8::Handle<v8::String> module_name) {
@@ skipping 42 matching lines @@
                                     const std::string& method_name) {
   v8::HandleScope handle_scope;
   v8::Local<v8::Value> module =
       v8::Local<v8::Value>::New(
           RequireForJsInner(v8::String::New(module_name.c_str())));
   if (module.IsEmpty() || !module->IsObject())
     return;
   v8::Local<v8::Value> value =
       v8::Handle<v8::Object>::Cast(module)->Get(
           v8::String::New(method_name.c_str()));
+  CallModuleMethod(value, 0, NULL);
+}
+
+v8::Handle<v8::Value> ModuleSystem::CallModuleMethod(
+    v8::Local<v8::Value> value,
+    int argc,
+    v8::Handle<v8::Value> argv[]) {
   if (value.IsEmpty() || !value->IsFunction())
-    return;
+    return v8::Handle<v8::Value>();
   v8::Handle<v8::Function> func =
       v8::Handle<v8::Function>::Cast(value);
   // TODO(jeremya/koz): refer to context_ here, not the current context.
   v8::Handle<v8::Object> global(v8::Context::GetCurrent()->Global());
+  v8::Handle<v8::Value> ret;
   {
     WebKit::WebScopedMicrotaskSuppression suppression;
     v8::TryCatch try_catch;
     try_catch.SetCaptureMessage(true);
-    func->Call(global, 0, NULL);
+    ret = func->Call(global, argc, argv);
     if (try_catch.HasCaught())
       HandleException(try_catch);
   }
+  return ret;
+}
+
+bool ModuleSystem::HasNativeHandler(const std::string& name) {
+  return native_handler_map_.find(name) != native_handler_map_.end();
 }
 
 void ModuleSystem::RegisterNativeHandler(const std::string& name,
     scoped_ptr<NativeHandler> native_handler) {
   native_handler_map_[name] =
       linked_ptr<NativeHandler>(native_handler.release());
 }
 
 void ModuleSystem::OverrideNativeHandler(const std::string& name) {
   overridden_native_handlers_.insert(name);
 }
 
 void ModuleSystem::RunString(const std::string& code, const std::string& name) {
   v8::HandleScope handle_scope;
   RunString(v8::String::New(code.c_str()), v8::String::New(name.c_str()));
 }
 
+v8::Handle<v8::Object> ModuleSystem::GetModule(
+    v8::Handle<v8::Object> parameters) {
+  NativesEnabledScope scope(this);
+  v8::Handle<v8::Object> module = v8::Handle<v8::Object>::Cast(
+      RequireForJsInner(
+          parameters->Get(v8::String::New(kModuleName))->ToString()));
+  return module;
+}
+
+v8::Handle<v8::Object> ModuleSystem::GetNativeModule(
+    v8::Handle<v8::Object> parameters) {
+  NativesEnabledScope scope(this);
+  std::string name = *v8::String::AsciiValue(
+      parameters->Get(v8::String::New(kModuleName))->ToString());
+  v8::Handle<v8::Object> module = v8::Handle<v8::Object>::Cast(
+      GetNativeFromString(name));
+  return module;
+}
+
+// static
+v8::Handle<v8::Value> ModuleSystem::NativeLazyFieldGetter(
+    v8::Local<v8::String> property, const v8::AccessorInfo& info) {
+  return BaseLazyFieldGetter(property, info, &ModuleSystem::GetNativeModule);
+}
+
 // static
 v8::Handle<v8::Value> ModuleSystem::LazyFieldGetter(
     v8::Local<v8::String> property, const v8::AccessorInfo& info) {
+  return BaseLazyFieldGetter(property, info, &ModuleSystem::GetModule);
+}
+
+// static
+v8::Handle<v8::Value> ModuleSystem::BaseLazyFieldGetter(
+    v8::Local<v8::String> property,
+    const v8::AccessorInfo& info,
+    GetModuleFunc get_module) {
   CHECK(!info.Data().IsEmpty());
   CHECK(info.Data()->IsObject());
   v8::HandleScope handle_scope;
   v8::Handle<v8::Object> parameters = v8::Handle<v8::Object>::Cast(info.Data());
   v8::Handle<v8::Object> global(v8::Context::GetCurrent()->Global());
   v8::Handle<v8::Value> module_system_value =
       global->GetHiddenValue(v8::String::New(kModuleSystem));
   if (module_system_value->IsUndefined()) {
     // ModuleSystem has been deleted.
     return v8::Undefined();
   }
   ModuleSystem* module_system = static_cast<ModuleSystem*>(
       v8::Handle<v8::External>::Cast(module_system_value)->Value());
 
-  v8::Handle<v8::Object> module;
-  {
-    NativesEnabledScope scope(module_system);
-    module = v8::Handle<v8::Object>::Cast(module_system->RequireForJsInner(
-        parameters->Get(v8::String::New(kModuleName))->ToString()));
-  }
+  v8::Handle<v8::Object> module = (module_system->*get_module)(parameters);
   if (module.IsEmpty())
     return handle_scope.Close(v8::Handle<v8::Value>());
 
   v8::Handle<v8::String> field =
       parameters->Get(v8::String::New(kModuleField))->ToString();
 
   return handle_scope.Close(module->Get(field));
 }
 
 void ModuleSystem::SetLazyField(v8::Handle<v8::Object> object,
                                 const std::string& field,
                                 const std::string& module_name,
                                 const std::string& module_field) {
+  SetLazyField(object, field, module_name, module_field,
+      &ModuleSystem::LazyFieldGetter);
+}
+
+void ModuleSystem::SetLazyField(v8::Handle<v8::Object> object,
+                                const std::string& field,
+                                const std::string& module_name,
+                                const std::string& module_field,
+                                v8::AccessorGetter getter) {
   v8::HandleScope handle_scope;
   v8::Handle<v8::Object> parameters = v8::Object::New();
   parameters->Set(v8::String::New(kModuleName),
                   v8::String::New(module_name.c_str()));
   parameters->Set(v8::String::New(kModuleField),
                   v8::String::New(module_field.c_str()));
 
   object->SetAccessor(v8::String::New(field.c_str()),
-                      &ModuleSystem::LazyFieldGetter,
+                      getter,
                       NULL,
                       parameters);
 }
 
+void ModuleSystem::SetNativeLazyField(v8::Handle<v8::Object> object,
+                                      const std::string& field,
+                                      const std::string& module_name,
+                                      const std::string& module_field) {
+  SetLazyField(object, field, module_name, module_field,
+      &ModuleSystem::NativeLazyFieldGetter);
+}
+
 v8::Handle<v8::Value> ModuleSystem::RunString(v8::Handle<v8::String> code,
                                               v8::Handle<v8::String> name) {
   v8::HandleScope handle_scope;
   WebKit::WebScopedMicrotaskSuppression suppression;
   v8::Handle<v8::Value> result;
   v8::TryCatch try_catch;
   try_catch.SetCaptureMessage(true);
   v8::Handle<v8::Script> script(v8::Script::New(code, name));
   if (try_catch.HasCaught()) {
     HandleException(try_catch);
@@ skipping 11 matching lines @@
     v8::Handle<v8::String> source_name) {
   v8::HandleScope handle_scope;
   std::string module_name = *v8::String::AsciiValue(source_name);
   if (!source_map_->Contains(module_name))
     return v8::Undefined();
   return handle_scope.Close(source_map_->GetSource(module_name));
 }
 
 v8::Handle<v8::Value> ModuleSystem::GetNative(const v8::Arguments& args) {
   CHECK_EQ(1, args.Length());
+  std::string native_name = *v8::String::AsciiValue(args[0]->ToString());
+  return GetNativeFromString(native_name);
+}
+
+v8::Handle<v8::Value> ModuleSystem::GetNativeFromString(
+    const std::string& native_name) {
   if (natives_enabled_ == 0)
     return ThrowException("Natives disabled");
-  std::string native_name = *v8::String::AsciiValue(args[0]->ToString());
   if (overridden_native_handlers_.count(native_name) > 0u)
-    return RequireForJs(args);
+    return RequireForJsInner(v8::String::New(native_name.c_str()));
   NativeHandlerMap::iterator i = native_handler_map_.find(native_name);
   if (i == native_handler_map_.end())
     return v8::Undefined();
   return i->second->NewInstance();
 }
 
 v8::Handle<v8::String> ModuleSystem::WrapSource(v8::Handle<v8::String> source) {
   v8::HandleScope handle_scope;
   v8::Handle<v8::String> left =
       v8::String::New("(function(require, requireNative, exports) {");
   v8::Handle<v8::String> right = v8::String::New("\n})");
   return handle_scope.Close(
       v8::String::Concat(left, v8::String::Concat(source, right)));
 }
 
 v8::Handle<v8::Value> ModuleSystem::ThrowException(const std::string& message) {
   return v8::ThrowException(v8::String::New(message.c_str()));
 }
 
 }  // extensions