public void Attack_ShouldThrowInvalidOperationExceptionWhenTheHeroHasNoHealth()
{
//Arrange
IHero hero = new HeroBuilder().WithHealth(0).Build();
IHero opponent = new HeroBuilder().Build();
//Act + Assert
Assert.That(() => hero.Attack(opponent), Throws.InstanceOf <InvalidOperationException>());
}
public void DefendAgainstAttack_SuperMode_ShouldDecrementHealthWithHalfAttackStrength()
{
//Arrange
int health = Random.Next(50, 100);
IHero hero = new HeroBuilder().WithSuperModeLikeliness(1).WithHealth(health).Build();
int attackStrength = Random.Next(1, hero.Health);
//Act
hero.DefendAgainstAttack(attackStrength);
//Assert
Assert.That(hero.Health, Is.EqualTo(health - attackStrength / 2));
}
public void Attack_SuperMode_ShouldAttackOpponentWithDoubleStrength()
{
//Arrange
IHero hero = new HeroBuilder().WithSuperModeLikeliness(1.0f).Build();
Mock <IHero> opponentMock = new HeroMockBuilder().Build();
//Act
hero.Attack(opponentMock.Object);
//Assert
opponentMock.Verify(opponent => opponent.DefendAgainstAttack(hero.Strength * 2), Times.Once,
$"Should call 'DefendAgainstAttack' of opponent with strength {hero.Strength * 2}.");
}
private static void AssertSuperModeLikelinessForDefend(float superModeLikeliness)
{
int numberOfDefends = 200;
int numberOfNormalDefends = 0;
int numberOfSuperDefends = 0;
for (int i = 0; i < numberOfDefends; i++)
{
int startHealth = Random.Next(60, 101);
int attackStrength = Random.Next(2, 20);
if (attackStrength % 2 != 0)
{
attackStrength += 1;
}
IHero hero = new HeroBuilder().WithSuperModeLikeliness(superModeLikeliness).WithHealth(startHealth).Build();
hero.DefendAgainstAttack(attackStrength);
int expectedHealthNormal = startHealth - attackStrength;
int expectedHealthSuperMode = startHealth - attackStrength / 2;
Assert.That(hero.Health, Is.EqualTo(expectedHealthNormal).Or.EqualTo(expectedHealthSuperMode),
$"After defending an attack of strength {attackStrength} with an initial health of {startHealth}, " +
$"the health of the hero should be {expectedHealthNormal} or {expectedHealthSuperMode}.");
if (hero.Health == expectedHealthNormal)
{
numberOfNormalDefends++;
}
else
{
numberOfSuperDefends++;
}
}
string staticRandomTip =
"Tip: make sure all 'Hero' instances use the same 'Random' instance by declaring a static field like this: 'private static Random Random = new Random();'";
Assert.That(numberOfNormalDefends, Is.GreaterThan(0),
$"Out of {numberOfDefends} defends, no normal defend happened. That is not random enough. {staticRandomTip}");
Assert.That(numberOfSuperDefends, Is.GreaterThan(0),
$"Out of {numberOfDefends} defends, no supermode defend happened. That is not random enough. {staticRandomTip}");
double actualSuperMode = numberOfSuperDefends / (double)numberOfDefends;
Assert.That(actualSuperMode, Is.EqualTo(superModeLikeliness).Within(0.15),
$"After {numberOfDefends} defends the supermode likeliness seems to be around {Convert.ToInt32(actualSuperMode * 100)}%. " +
$"It should be around {Convert.ToInt32(superModeLikeliness * 100)}%. {staticRandomTip}");
}
private void AssertSuperModeLikelinessForAttack(float superModeLikeliness)
{
IHero hero = new HeroBuilder().WithSuperModeLikeliness(superModeLikeliness).Build();
int numberOfAttacks = 200;
int numberOfNormalAttacks = 0;
int numberOfSuperAttacks = 0;
for (int i = 0; i < numberOfAttacks; i++)
{
Mock <IHero> opponentMock = new HeroMockBuilder().Build();
opponentMock.Setup(opponent => opponent.DefendAgainstAttack(It.IsAny <int>()))
.Callback((int attackStrength) =>
{
if (attackStrength == hero.Strength)
{
numberOfNormalAttacks++;
}
else if (attackStrength == hero.Strength * 2)
{
numberOfSuperAttacks++;
}
});
hero.Attack(opponentMock.Object);
}
Assert.That(numberOfNormalAttacks, Is.GreaterThan(0),
$"Out of {numberOfAttacks} attacks, no normal attack happened. That is not random enough.");
Assert.That(numberOfSuperAttacks, Is.GreaterThan(0),
$"Out of {numberOfAttacks} attacks, no supermode attack happened. That is not random enough.");
Assert.That(numberOfSuperAttacks + numberOfNormalAttacks, Is.EqualTo(numberOfAttacks),
$"The amount of normal attacks ({numberOfNormalAttacks}) " +
$"added with the number of supermode attacks ({numberOfSuperAttacks}) " +
$"should be equal to the total number of attacks ({numberOfAttacks}).");
double actualSuperMode = numberOfSuperAttacks / (double)numberOfAttacks;
Assert.That(actualSuperMode, Is.EqualTo(hero.SuperModeLikeliness).Within(0.15),
$"After {numberOfAttacks} attacks the supermode likeliness seems to be around {Convert.ToInt32(actualSuperMode * 100)}%. " +
$"It should be around {Convert.ToInt32(hero.SuperModeLikeliness * 100)}%.");
}
public void ShouldNotifyChangesInHealth()
{
HeroBuilder builder = new HeroBuilder().WithHealth(100);
IHero hero = builder.Build();
INotifyPropertyChanged notifier = hero as INotifyPropertyChanged;
Assert.That(notifier, Is.Not.Null,
"Hero class should implement an interface that enables property change notifications.");
IList <string> changedProperties = new List <string>();
notifier.PropertyChanged += (sender, args) =>
{
changedProperties.Add(args.PropertyName);
};
//trigger Health change
builder.WithHealth(50);
Assert.That(changedProperties.FirstOrDefault(), Is.EqualTo(nameof(IHero.Health)), "A change in Health is not notified.");
}