为什么即使我在 NSubstitute 中安排方法，它总是返回 Null 结果？

Question

I try to Arrange a factory to return a service instance.

And then I arrange this service, however the method in the service always return null, even I arrange the mehod, why?

Here is my sample code, could somebody help me on this? Thanks in advance!

using Moq;
using NSubstitute;
using Xunit;

namespace ConsoleApp1
{
    public interface IFactory
    {
        IMyService CreateInService(int number);
    }
    public  interface IMyService
    {
        (Status?,Status?)GetName(string name);
    }
    
    public enum Status
    {
        UnKnown = 0,
    }
    
    public class TupleTest
    {

        [Fact]
        public void GetTupleTest()
        {
            (Status?,Status?) exceptedStatusTuple = (Status.UnKnown,Status.UnKnown);
            
            var factory = Substitute.For<IFactory>();
            var myService = Substitute.For<IMyService>();

            factory.CreateInService(It.IsAny<int>()).Returns(myService);
            myService.GetName(It.IsAny<string>()).ReturnsForAnyArgs(exceptedStatusTuple);

            var result = factory.CreateInService(100).GetName("test");
            
            //result.item1 is null, it should be Status.UnKnown!
            Assert.Equal(result.Item1,exceptedStatusTuple.Item1);
            //result.item2 is null,it should be Status.UnKnown!
            Assert.Equal(result.Item2,exceptedStatusTuple.Item2);
        }
    }
}

Answer 1

It looks like you are mixing up Moq and NSubstitute calls. Try commenting out the using Moq; line and fix the compile errors with that test.

One example I can see is It.IsAny is a Moq call. It will need to be Arg.Any for NSubstitute.