public void Custom_Test()
{
    var first = new Argument<string>(name: "first", parse: ctx =>
    {
        ctx.OnlyTake(0);
        return null;
    })
    {
        Arity = ArgumentArity.ZeroOrOne
    };

    var second = new Argument<string[]>(name: "second", parse: ctx =>
    {
        ctx.OnlyTake(0);
        return null;
    })
    {
        Arity = ArgumentArity.ZeroOrMore
    };

    var third = new Argument<string[]>(name: "third")
    {
        Arity = ArgumentArity.ZeroOrMore
    };

    var command = new RootCommand
    {
        first,
        second,
        third
    };

    var result = command.Parse("1");

    result.GetValueForArgument(first).Should().BeNull();
    result.GetValueForArgument(second).Should().BeEmpty();
    result.GetValueForArgument(third).Should().BeEquivalentSequenceTo("1");
           
}