public void GetsPriceOnInstantiation()
{
//Arrange
PricingManager manager = new PricingManager(1.00);
//Act
FuelPriceDisplay display = new FuelPriceDisplay(manager);
//Assert
Assert.AreEqual(1.0, display.FuelPrice);
}
public void AddObserverAddsObserver()
{
//Arrange
PricingManager manager = new PricingManager();
FuelPriceDisplay display = new FuelPriceDisplay(manager);
//Act
manager.AddObserver(display);
//Assert
Assert.AreEqual(1, manager.Observers.Count);
}
public void GetsNotifiedonFuelPriceChange()
{
//Arrange
PricingManager manager = new PricingManager();
FuelPriceDisplay display = new FuelPriceDisplay(manager);
manager.AddObserver(display);
//Act
manager.UpdateFuelPrice(1.78);
//Assert
Assert.AreEqual(1.78, display.FuelPrice);
}
public void RemoveObserverRemovesObserver()
{
//Arrange
PricingManager manager = new PricingManager();
FuelPriceDisplay display = new FuelPriceDisplay(manager);
Terminal terminal = new Terminal(manager);
//Act
manager.AddObserver(display);
manager.AddObserver(terminal);
manager.RemoveObserver(display);
//Assert
Assert.AreEqual(1, manager.Observers.Count);
}