Random relay customization

RandomRelayCustomization.cs

public class RandomRelayCustomization : ISpecimenBuilder
{
    private readonly List<ISpecimenBuilder> builders;
    private readonly IEnumerator<int> randomizer;

    public RandomRelayCustomization(params ISpecimenBuilder[] builders)
        : this(builders.AsEnumerable())
    {
    }

    public RandomRelayCustomization(IEnumerable<ISpecimenBuilder> builders)
    {
        if (builders is null)
        {
            throw new ArgumentNullException(nameof(builders));
        }

        this.builders = builders.ToList();
        this.randomizer = new RoundRobinSequence(0, this.builders.Count - 1)
            .GetEnumerator();
    }

    public object Create(object request, ISpecimenContext context)
    {
        this.randomizer.MoveNext();
        var builder = this.builders[this.randomizer.Current];
        return builder.Create(request, context);
    }
}

RoundRobinSequence.cs

public class RoundRobinSequence : IEnumerable<int>
{
    private readonly int min;
    private readonly int max;
    private int current;

    public RoundRobinSequence(int min, int max)
    {
        this.min = min;
        this.max = max;
        this.current = min;
    }

    public IEnumerator<int> GetEnumerator()
    {
        while (true)
        {
            this.current++;
            if (this.current > this.max)
            {
                this.current = this.current % 2 == 0 ? this.min + 1 : this.min;
            }
            yield return this.current;
            this.current++;
        }
    }

    IEnumerator IEnumerable.GetEnumerator()
    {
        return this.GetEnumerator();
    }
}