Adding objects to a ShadowRealm

[AaronRPrince]

After reading through #789 I've been trying to set up a shadow realm to use as an isolated context. It looks like it could work, but I don't see an easy way to dynamically add objects from C#.

// manually writing the object works as expected
var engine = new Engine();
var sr = engine.Realm.Intrinsics.ShadowRealm.Construct();
sr.Evaluate("var obj = { prop: 100 };");

sr.Evaluate("obj.prop + 100");     // output: 200               - expected
engine.Evaluate("obj.prop + 100"); // error: obj is not defined - expected

What I've tried:

// JsObject.ToString() doesn't serialize the object to JSON.
sr.Evaluate($"var obj = {JsObject.FromObject(sr.Engine, new { prop = 100 })};"); // error: unexpected token

// value passing between realms must be callable or primitive
var func = sr.Evaluate("(obj) => obj.prop + 100");
Engine.Invoke(func, new { Prop = 1 }); // error: result is not callable - sort of expected

// this just sets a prop on the ShadowRealm object itself
sr.Set("obj", JsValue.FromObject(sr.Engine, new { prop = 100 })); 

sr.Evaluate("obj.prop + 100");     // error: obj is not defined - expected
engine.Evaluate("obj.prop + 100"); // error: obj is not defined - expected

// both of these set the value in the global realm not the shadow realm
sr.Engine.SetValue("obj", new { prop = 100 });    
sr.Engine.Realm.GlobalObject.Set("obj", JsValue.FromObject(sr.Engine, new { prop = 100 }));

sr.Evaluate("obj.prop + 100");                    // Cross-Realm Error: obj is not defined
engine.Evaluate("obj.prop + 100");                // output: 200

A work around is either manually serializing the object with Json.NET, System.Text.Json, etc. -- or reflecting the internal realm from the ShadowRealm and setting the global state of that:

var realm = (Realm) sr.GetType().GetField("_shadowRealm", BindingFlags.NonPublic | BindingFlags.Instance)!.GetValue(sr);
realm.GlobalObject.Set("obj", JsValue.FromObject(sr.Engine, new { prop = 100 }));

sr.Evaluate("obj.prop + 100");     // output: 200               - works
engine.Evaluate("obj.prop + 100"); // error: obj is not defined - expected

Question
My question is,from the C# side, am I missing a way to add non-primitive values to a ShadowRealm before or after creating it?

Request
If I'm not, my request is to add a SetValue method to ShadowRealm. That would help make it more usable for non-primitive values. I understand that within JavaScript non-callable, non-primitive values can't cross realms, but between JavaScript and C# we should be able to inject dynamic objects when creating a ShadowRealm. Otherwise re-looking at #789 would be nice.

[lahma]

Seems that you are after #1573

[AaronRPrince]

I missed that. Thanks for the quick answer.