Mock Object Won't Return an int (i.e. Value Type)

[Alfetta159]

When setting up a method in the interface to return an int, I just get a zero (default int).

    public class UnitTest1
    {
        [Fact]
        public async Task Test1()
        {
            var mockRepo1 = new Mock<IToBeTested>();
            mockRepo1.Setup(r => r.Method(45)).Returns(42);

            var mockRepo2 = new Mock<IToBeTested>();
            mockRepo2.Setup(r => r.MethodAsync(42)).ReturnsAsync(45);
           
            //I just get a zero returned.
            Assert.Equal(42, mockRepo1.Object.Method(45));
            Assert.Equal(45, await mockRepo1.Object.MethodAsync(42));
        }

        public interface IToBeTested
        {
            int Method(int input);
            Task<int> MethodAsync(int input);
        }
    }

[stakx]

You've got a typo:

Assert.Equal(45, await mockRepo1.Object.MethodAsync(42));

should be:

Assert.Equal(45, await mockRepo2.Object.MethodAsync(42));
//                             ^

[Alfetta159]

Thank you, I thought I was getting the same error because of a possible bug, but I see it was a mistake in my example.

So I went back and looked at what I was actually doing and realized that my example was using a Value type and not a class, and my original code is using two separate instances of the same class, and I did not override the Equals method.

Thx.

    public class UnitTest1
    {
        [Fact]
        public async Task Test1()
        {
            var mockRepo1 = new Mock<IToBeTested>();
            mockRepo1.Setup(r => r.MethodAsync(null)).ReturnsAsync(45);

            var result1 = await mockRepo1.Object.MethodAsync(null);

            Assert.Equal(45, result1);//Good

            var testinstance = new TestClass
            {
                Id = 0,
                DisplayName = "Display",
            };
            var mockRepo3 = new Mock<IToBeTested>();
            mockRepo3.Setup(r => r.MethodAsync(testinstance)).ReturnsAsync(45);

            var result3 = await mockRepo3.Object.MethodAsync(testinstance);//Good

            //I just get a zero returned.
            Assert.Equal(45, result3);

            var mockRepo2 = new Mock<IToBeTested>();
            mockRepo2.Setup(r => r.MethodAsync(new TestClass
            {
                Id = 0,
                DisplayName = "Display",
            })).ReturnsAsync(45);

            var result2 = await mockRepo2.Object.MethodAsync(new TestClass
            {
                Id = 0,
                DisplayName = "Display",
            });

            Assert.Equal(45, result2);//Only works if Equals is overridden

        }

        public interface IToBeTested
        {
            Task<int> MethodAsync(object input);
        }

        class TestClass
        {
            public int Id { get; set; }
            public string Name { get; set; }
            public string DisplayName { get; set; }

            public override bool Equals(object obj)
            {
                var input = obj as TestClass;

                if (input != null)
                    return Id == input.Id && Name == input.Name && DisplayName == input.DisplayName;
                else
                    return false;
            }

            //public override int GetHashCode()
            //{
            //    return Id.GetHashCode() ^ Name.GetHashCode() ^ DisplayName.GetHashCode();
            //}
        }
    }