Len metamethod returns nil regardless of implementation

[julcreutz]

The Len metamethod does not return the value its given by the context return value.

[Metamethods.Len] = new LuaFunction(Metamethods.Index, (context, _) =>
{
    var userData = context.GetArgument<LuaVariable>(0);
    return new ValueTask<int>(context.Return(userData.count));
})

At the point of call, userData.count was 3.
When printing out the result to the console from within the lua state, nil is printed however.