public void Should_Output5Point2_WhenDoind2Point1Add3Point1()
        {
            //arrange
            var outputServise = new Mock<IOutputServise>();
            var calculator = new CalculatorEngine(outputServise.Object);

            //act
            calculator.Add(2.1, 3.1);

            //assert
            outputServise.Verify(x => x.Output(5.2), Times.Once());
        }
        public void Should_Return5Poin2_WhenDoind2Point1Add3Point1()
        {
            //arrange
            var outputServise = new Mock<IOutputServise>();
            var calculator = new CalculatorEngine(outputServise.Object);
            string expectedResult = "5,2000";

            //act
            calculator.Add(2.1, 3.1);

            //assert
            Assert.AreEqual(calculator.correctResult, expectedResult);
        }