public void GivenInput_asdf_ShouldThrowException()
        {
            _inputManager.GetInput().Returns("asdf");
            var numberGetter = new NumberGetter(_inputManager, _displayManager);

            Assert.Throws <ArgumentException>(() => numberGetter.GetNumber());
        }
        public void GivenInput_10_ShouldReturn10()
        {
            _inputManager.GetInput().Returns("10");
            var numberGetter = new NumberGetter(_inputManager, _displayManager);

            var actual = numberGetter.GetNumber();

            Assert.AreEqual(10, actual);
        }