private static UnityContainer Init(string fileName)
        {
            var container = new UnityContainer();

            var directoryName = Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
            container.RegisterInstance(FILE_PATH, Path.Combine(directoryName, fileName));

            var calculator = new Model.Calculator();
            container.RegisterInstance<ICalculator>(calculator);
            container.RegisterType(typeof(ICommand), typeof(AddCommand), ADD);
            container.RegisterType(typeof(ICommand), typeof(MultiplyCommand), MULTIPLY);
            container.RegisterType(typeof(ICommand), typeof(ApplyCommand), APPLY);

            return container;
        }
 public void SetUp()
 {
     calculator = new Model.Calculator();
 }