Issue 5570 - Make V8 isolate injectable into JsEngine

src/JsEngine.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 54 matching lines @@
     }
     v8::Platform* platform;
   public:
     static void Init()
     {
       // it's threadsafe since C++11 and it will be instantiated only once and
       // destroyed at the application exit
       static V8Initializer initializer;
     }
   };
+
+  /**
+  * Scope based isolate manager. Creates a new isolate instance on
+  * constructing and disposes it on destructing. In addition it initilizes V8.
+  */
+  class ScopedV8Isolate : public AdblockPlus::IV8IsolateProvider
+  {
+  public:
+    ScopedV8Isolate()
+    {
+      V8Initializer::Init();
+      v8::Isolate::CreateParams isolateParams;
+      isolateParams.array_buffer_allocator = v8::ArrayBuffer::Allocator::NewDefaultAllocator();
+      isolate = v8::Isolate::New(isolateParams);
+    }
+
+    ~ScopedV8Isolate()
+    {
+      isolate->Dispose();
+      isolate = nullptr;
+    }
+
+    v8::Isolate* Get() override
+    {
+      return isolate;
+    }
+  private:
+    ScopedV8Isolate(const ScopedV8Isolate&);
+    ScopedV8Isolate& operator=(const ScopedV8Isolate&);
+
+    v8::Isolate* isolate;
+  };
 }
 
 using namespace AdblockPlus;
 
-AdblockPlus::ScopedV8Isolate::ScopedV8Isolate()
-{
-  V8Initializer::Init();
-  v8::Isolate::CreateParams isolateParams;
-  isolateParams.array_buffer_allocator = v8::ArrayBuffer::Allocator::NewDefaultAllocator();
-  isolate = v8::Isolate::New(isolateParams);
-}
-
-AdblockPlus::ScopedV8Isolate::~ScopedV8Isolate()
-{
-  isolate->Dispose();
-  isolate = nullptr;
-}
-
 JsEngine::JsWeakValuesList::~JsWeakValuesList()
 {
 }
 
 void JsEngine::NotifyLowMemory()
 {
   const JsContext context(*this);
   GetIsolate()->MemoryPressureNotification(v8::MemoryPressureLevel::kCritical);
 }
 
@@ skipping 20 matching lines @@
 void JsEngine::CallTimerTask(const JsWeakValuesID& timerParamsID)
 {
   auto timerParams = TakeJsValues(timerParamsID);
   JsValue callback = std::move(timerParams[0]);
 
   timerParams.erase(timerParams.begin()); // remove callback placeholder
   timerParams.erase(timerParams.begin()); // remove timeout param
   callback.Call(timerParams);
 }
 
-AdblockPlus::JsEngine::JsEngine(Platform& platform)
+AdblockPlus::JsEngine::JsEngine(Platform& platform, std::unique_ptr<IV8IsolateProvider> isolate)
   : platform(platform)
+  , isolate(std::move(isolate))
 {
 }
 
 AdblockPlus::JsEnginePtr AdblockPlus::JsEngine::New(const AppInfo& appInfo,
-  Platform& platform)
+  Platform& platform, std::unique_ptr<IV8IsolateProvider> isolate)
 {
-  JsEnginePtr result(new JsEngine(platform));
+  if (!isolate)
+  {
+    isolate.reset(new ScopedV8Isolate());
+  }
+  JsEnginePtr result(new JsEngine(platform, std::move(isolate)));
 
   const v8::Locker locker(result->GetIsolate());
   const v8::Isolate::Scope isolateScope(result->GetIsolate());
   const v8::HandleScope handleScope(result->GetIsolate());
 
   result->context.reset(new v8::Global<v8::Context>(result->GetIsolate(),
     v8::Context::New(result->GetIsolate())));
   auto global = result->GetGlobalObject();
   AdblockPlus::GlobalJsObject::Setup(*result, appInfo, global);
   return result;
@@ skipping 148 matching lines @@
     list.push_back(JsValue(shared_from_this(), arguments[i]));
   return list;
 }
 
 void AdblockPlus::JsEngine::SetGlobalProperty(const std::string& name,
                                               const AdblockPlus::JsValue& value)
 {
   auto global = GetGlobalObject();
   global.SetProperty(name, value);
 }