Why is Unit Testing So Hard? - Example 1

why-is-unit-testing-so-hard-1.cs

public class StrongWeapon : Weapon
{
  public override double Damage => 5.0;
}

public class Player
{
  private Weapon _weapon;
  
  public double Damage => _weapon.Damage;
}

public class PlayerView
{
  private Player _player;
  
  public string WeaponLabelText => $"Weapon Damage: {_player.Damage}";
}

why-is-unit-testing-so-hard-2.cs

public class PlayerTests
{
  [Test]
  public void StrongWeaponDamage()
  {
    var weapon = new StrongWeapon();
    
    Assert.AreEqual(5.0, new Player(weapon).Damage);
  }
}

public class PlayerViewTests
{
  [Test]
  public void StrongWeaponLabelText()
  {
    var weapon = new StrongWeapon();
    var player = new Player(weapon);
    
    Assert.AreEqual("Weapon Damage: 5", new PlayerView(player).WeaponLabelText);
  }
}