why-unit-testing-is-so-hard-6.cs

public class Player
{
  private const double MaxPowerups = 2;
  
  private Weapon _weapon;
  
  public List<IPowerup> Powerups { get; } = new List<IPowerup>();
  
  public double Damage => _weapon.Damage * Powerups.Take(MaxPowerups).Sum(p => p.Multiplier);
}