how to test IQueryable of strongly typed using xUnit in .NET CORE - asp.net-web-api

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);
}