如何在 .NET CORE 中使用 xUnit 测试强类型的 IQueryable

Question

I am working on a test project for .NET CORE Web API project. I have SchoolService class that implements numbers of methods as some of them below

Service Class

 public class SchoolService : ISchoolService
{
    private readonly ISchoolEntity schoolEntity;

    public SchoolService(ISchoolEntity schoolEntity)
    {
        this.schoolEntity = schoolEntity;
    }


    public IQueryable<SchoolDataView> GetAllSchools()
    {
        var query = this.schoolEntity.GetAllSchool();
        return query;
    }

    public SchoolDataView GetSchoolById(Guid Id)
    {
        var query = this.schoolEntity.GetSchoolById(Id);
        return query;
    }

I want to test 1- GetAllSchools return object type is of IQueryable? 2- How I use autofix or by another way for schoolEntity.GetAllSchool() return fake IQueryable?

Service Test

 public class SchoolServiceTests
{
    private readonly ISchoolService schoolService;
    private readonly ISchoolEntity schoolEntity = Substitute.For<ISchoolEntity>();

    public SchoolServiceTests()
    {
        schoolService = new SchoolService(schoolEntity);
    }

    [Fact]
    public void GetAllSchool_ShouldReturn_IQueryableOfSchoolDataView()
    {
        //Arrange


        //Act
        var a = schoolEntity.GetAllSchool();

        //Assert
        Assert.??
    }
}

Answer 1

I have written following test to achieve behaviour that I have stated in my question. Open to hearing more feedback and suggestions on it. Thanks

    [Fact]
    public void GetAllSchool_ShouldReturn_IQueryableOfSchoolDataView()
    {
        //Arrange
  
        var schoolDataViewList = new List<SchoolDataView>
        {
            new SchoolDataView { SchoolID = Guid.NewGuid(), Name = "London Primary School"},
            new SchoolDataView { SchoolID = Guid.NewGuid(), Name = "Windsor Gramer School"},
            new SchoolDataView { SchoolID = Guid.NewGuid(), Name = "Kings College"},
            new SchoolDataView { SchoolID = Guid.NewGuid(), Name = "Reading School"}
        }.AsQueryable();

        schoolEntity.GetAllSchool().Returns(schoolDataViewList);

        //Act
        var actualSchoolList = sut.GetAllSchools();

        //Assert
        Assert.IsAssignableFrom<IQueryable<SchoolDataView>>(actualSchoolList);
    }

OR Using AutoFixture

 [Fact]
    public void GetAllSchool_ShouldReturn_IQueryableOfSchoolDataView()
    {
        //Arrange
        var fixture = new Fixture();

        var schoolDataViewMock = fixture.CreateMany<SchoolDataView>();
       
        schoolEntity.GetAllSchool().Returns(schoolDataViewMock.AsQueryable());

        //Act
        var actualSchoolDataList = sut.GetAllSchools();

        //Assert
        Assert.IsAssignableFrom<IQueryable<SchoolDataView>>(actualSchoolDataList);
    }