How to reset the state of the engine between calls?

[smadurange]

I'm using Jint 2.11.58v. I'm trying to understand how to use the engine's EnterExecutionContext/LeaveExecutionContext methods. I would like to reset the engine after a certain operation. For example, in the following code, I don't expect to see name printed as foo but it does.

static void Main(string[] args)
{
    var engine = new Engine();

    for (int i = 0; i < 2; i++)
    {
        if (i == 0)
        {
            var ctx = engine.ExecutionContext;
            var lexEnv = LexicalEnvironment.NewDeclarativeEnvironment(engine, ctx.LexicalEnvironment);
            var varEnv = LexicalEnvironment.NewDeclarativeEnvironment(engine, ctx.VariableEnvironment);
            engine.EnterExecutionContext(lexEnv, varEnv, ctx.ThisBinding);
            var x = engine.SetValue("name", "foo");
            Console.WriteLine("First " + engine.GetValue("name"));
            engine.LeaveExecutionContext();
        }
        else
        {
            Console.WriteLine("Second " + engine.GetValue("name"));
        }
    }
}

Is there any other way I can reset the state of the engine between calls?

[lahma]

#789 tries to solve this by allowing you to enter temporary context which is tried to be cleaned after usage.

[lahma]

ShadowRealm was merged to main and it might contain the functionality requested here, see Jint test case how it isolates a playground from the actual engine.

[scarletquasar]

Currently, in MelonJS I am using a quick "dirty" hack: recreating the engine as new everytime I want to restart it and injecting what I want. It is not the best solution here, but for a PoC is working fine.

engine.SetValue("__reset_current_execution__", new Action(() => {
  EngineManager.ResetEngine();
  engine.SetupFor(BuiltInJsModule.LibrariesAndPolyfills, currentApp, container);
  engine.SetupFor(BuiltInJsModule.Engine, currentApp, container);
  engine.SetupFor(BuiltInJsModule.Application, currentApp, container);
  engine.SetupFor(BuiltInJsModule.Environment, currentApp, container);
  engine.SetupFor(BuiltInJsModule.InputOutput, currentApp, container);
  engine.SetupFor(BuiltInJsModule.UnsafeScripting, currentApp, container);
  engine.SetupFor(BuiltInJsModule.DataManagement, currentApp, container);
  engine.SetupFor(BuiltInJsModule.HttpOperations, currentApp, container);
  engine.SetupFor(BuiltInJsModule.Tools, currentApp, container);
  engine.SetupFor(BuiltInJsModule.Debug, currentApp, container);
  engine.SetupFor(BuiltInJsModule.Database, currentApp, container);
}));

public static void ResetEngine()
{
    JintStatic.CurrentJintEngine = new();
}