[Experimental] Fixes promises evaluation

src/Context.cpp

@@ -199,7 +199,17 @@ py::object CContext::Evaluate(const std::string& src,
 
     CScriptPtr script = engine.Compile(src, name, line, col);
 
-    return script->Run();
+    boost::python::api::object result = script->Run();
+
+    while (v8::platform::PumpMessageLoop(
+        CPlatform::GetPlatform(),
+        v8::Isolate::GetCurrent(),
+        v8::platform::MessageLoopBehavior::kDoNotWait
+    )) {
+        v8::Isolate::GetCurrent()->PerformMicrotaskCheckpoint();
+    }
+
+    return result;
 }
 
 py::object CContext::EvaluateW(const std::wstring& src,
@@ -210,5 +220,15 @@ py::object CContext::EvaluateW(const std::wstring& src,
 
     CScriptPtr script = engine.CompileW(src, name, line, col);
 
-    return script->Run();
+    boost::python::api::object result = script->Run();
+
+    while (v8::platform::PumpMessageLoop(
+        CPlatform::GetPlatform(),
+        v8::Isolate::GetCurrent(),
+        v8::platform::MessageLoopBehavior::kDoNotWait
+    )) {
+        v8::Isolate::GetCurrent()->PerformMicrotaskCheckpoint();
+    }
+
+    return result;
 }

src/Platform.cpp

@@ -20,3 +20,8 @@ void CPlatform::Init()
 
     inited = true;
 }
+
+v8::Platform *CPlatform::GetPlatform(void)
+{
+    return CPlatform::platform.get();
+}

src/Platform.h

@@ -29,4 +29,5 @@ class CPlatform
     CPlatform(std::string argv0) : argv(argv0) {};
     ~CPlatform() {};
     void Init();
+    static v8::Platform *GetPlatform(void);
 };