Make JsEngine::Evaluate() return a wrapper for v8::Value to accessdifferent variable types easily

src/JsEngine.cpp

 #include <AdblockPlus.h>
 #include <sstream>
 
 #include "GlobalJsObject.h"
+#include "Utils.h"
 
 namespace
 {
   v8::Handle<v8::Context> CreateContext(
-    AdblockPlus::ErrorCallback& errorCallback,
-    AdblockPlus::WebRequest& webRequest)
+    v8::Isolate* isolate,
+    AdblockPlus::FileSystem& fileSystem,
+    AdblockPlus::WebRequest& webRequest,
+    AdblockPlus::ErrorCallback& errorCallback)
   {
-    const v8::Locker locker(v8::Isolate::GetCurrent());
+    const v8::Locker locker(isolate);
     const v8::HandleScope handleScope;
     const v8::Handle<v8::ObjectTemplate> global =
-      AdblockPlus::GlobalJsObject::Create(errorCallback, webRequest);
+      AdblockPlus::GlobalJsObject::Create(fileSystem, webRequest,
+                                          errorCallback);
     return v8::Context::New(0, global);
   }
 
   v8::Handle<v8::Script> CompileScript(const std::string& source, const std::string& filename)
   {
     const v8::Handle<v8::String> v8Source = v8::String::New(source.c_str());
     if (filename.length())
     {
       const v8::Handle<v8::String> v8Filename = v8::String::New(filename.c_str());
       return v8::Script::Compile(v8Source, v8Filename);
     }
     else
       return v8::Script::Compile(v8Source);
   }
 
   void CheckTryCatch(const v8::TryCatch& tryCatch)
   {
     if (tryCatch.HasCaught())
       throw AdblockPlus::JsError(tryCatch.Exception(), tryCatch.Message());
-  }
-
-  std::string Slurp(std::istream& stream)
-  {
-    std::stringstream content;
-    content << stream.rdbuf();
-    return content.str();
   }
 
   std::string ExceptionToString(const v8::Handle<v8::Value> exception,
       const v8::Handle<v8::Message> message)
   {
     std::stringstream error;
     error << *v8::String::Utf8Value(exception);
     if (!message.IsEmpty())
     {
       error << " at ";
       error << *v8::String::Utf8Value(message->GetScriptResourceName());
       error << ":";
       error << message->GetLineNumber();
     }
     return error.str();
   }
 }
 
 AdblockPlus::JsError::JsError(const v8::Handle<v8::Value> exception,
     const v8::Handle<v8::Message> message)
   : std::runtime_error(ExceptionToString(exception, message))
 {
 }
 
-AdblockPlus::JsEngine::JsEngine(const FileReader* const fileReader,
+AdblockPlus::JsEngine::JsEngine(FileSystem* const fileSystem,
                                 WebRequest* const webRequest,
                                 ErrorCallback* const errorCallback)
-  : fileReader(fileReader), context(CreateContext(*errorCallback, *webRequest))
+  : fileSystem(fileSystem), isolate(v8::Isolate::GetCurrent()),
+    context(CreateContext(isolate, *fileSystem, *webRequest, *errorCallback))
 {
 }
 
 AdblockPlus::JsValuePtr AdblockPlus::JsEngine::Evaluate(const std::string& source,
     const std::string& filename)
 {
-  const v8::Locker locker(v8::Isolate::GetCurrent());
-  const v8::HandleScope handleScope;
-  const v8::Context::Scope contextScope(context);
+  const Context context(*this);
   const v8::TryCatch tryCatch;
   const v8::Handle<v8::Script> script = CompileScript(source, filename);
   CheckTryCatch(tryCatch);
   v8::Local<v8::Value> result = script->Run();
   CheckTryCatch(tryCatch);
-  return JsValuePtr(new JsValue(v8::Isolate::GetCurrent(), context, result));
+  return JsValuePtr(new JsValue(*this, result));
 }
 
 void AdblockPlus::JsEngine::Load(const std::string& scriptPath)
 {
-  const std::auto_ptr<std::istream> file = fileReader->Read(scriptPath);
-  if (!*file)
+  const std::tr1::shared_ptr<std::istream> file = fileSystem->Read(scriptPath);
+  if (!file || !*file)
     throw std::runtime_error("Unable to load script " + scriptPath);
-  Evaluate(Slurp(*file));
+  Evaluate(Utils::Slurp(*file));
 }
 
 void AdblockPlus::JsEngine::Gc()
 {
   while (!v8::V8::IdleNotification());
 }
+
+AdblockPlus::JsValuePtr AdblockPlus::JsEngine::NewValue(const std::string& val)
+{
+  const Context context(*this);
+  return JsValuePtr(new JsValue(*this, v8::String::New(val.c_str(), val.length())));
+}
+
+AdblockPlus::JsValuePtr AdblockPlus::JsEngine::NewValue(int64_t val)
+{
+  const Context context(*this);
+  return JsValuePtr(new JsValue(*this, v8::Integer::New(val)));
+}
+
+AdblockPlus::JsValuePtr AdblockPlus::JsEngine::NewValue(bool val)
+{
+  const Context context(*this);
+  return JsValuePtr(new JsValue(*this, v8::Boolean::New(val)));
+}
+
+AdblockPlus::JsEngine::Context::Context(const JsEngine& jsEngine)
+    : locker(jsEngine.isolate), handleScope(),
+      contextScope(jsEngine.context)
+{
+}