How to use an enum when resolving an external key in a federated graph?

[SebBrookfield]

Hi,

I'm not sure if this is a bug or not, but I'm struggling to use an enum as a key when resolving an external reference.
If I try to use the ResolveReferenceWith() extension, I find that the enum is defaulted to the default value.

Take the following example:

using HotChocolate.Types;

namespace HotChocolateExample;

public enum Options
{
    OptionA,
    OptionB
}

public class Example
{
    public string Id { get; set; }
    public Options Option { get; set; }
}

public class ExampleType : ObjectType<Example>
{
    protected override void Configure(IObjectTypeDescriptor<Example> descriptor)
    {
        descriptor
            .ExtendServiceType()
            .Key("id option")
            .ResolveReferenceWith(example => CreateExample(example.Id, example.Option));

        descriptor
            .Field(t => t.Id)
            .External();

        descriptor
            .Field(t => t.Option)
            .External();
    }

    private static Example CreateExample(string id, Options option) => new() { Id = id, Option = option};
}

In the above example, the option passed to CreateExample is always "OptionA". If I change the type to String and don't update the supergraph schema, it works. (But I can't now compile the supergraph because the types don't match anymore)

My way around this at the moment is to access the LocalContextData["data"] and manually parse the enum.
I'm assuming this is to do with the fact that it's a string value being passed to the subgraph.

I've tried using a EnumType class, but this doesn't seem to do anything.

Could anyone help at all?
Hopefully this is clear.