how to resolve dependency injection in xunit? - unit-testing

Question

I have a problem in creating a test unit using xunit for my services that use dependency injection.
How can i send my dependency to test class?
[Fact]
public async Task GetAllRequestsHavePagingNoFilterNoSortAsync()
{
requestViewModel.RemotePaging = true;
requestViewModel.PageSize = 10;
requestViewModel.Page = 1;
var x = await requestService.GetAsync(requestViewModel);
Assert.NotNull(x);
Assert.True(x.PageCount == requestViewModel.PageSize);
}

Answer 1

You need to mock the dependencies using another library, the most popular one is Moq
So, assuming you have a class like this with a dependency injected:
public class ScrapedJobService : IScrapedJobService
{
private readonly IScrapedJobRepository _scrapedJobRepository;
public ScrapedJobService(IScrapedJobRepository scrapedJobRepository)
{
_scrapedJobRepository = scrapedJobRepository;
}
public WorkingPlace FindWorkingPlace(string title)
{
...
}
}
You need mock that dependency like this:
using Moq;
using Xunit;
private readonly ScrapedJobService _sut;
private readonly Mock<IScrapedJobRepository> _scrapedJobRepo = new Mock<IScrapedJobRepository>();
public ScrapedJobServiceTest()
{
_sut = new ScrapedJobService(_scrapedJobRepo.Object);
}
[Fact]
public void Test()
{
var result = _sut.FindWorkingPlace("Remote");
Assert.Equal(WorkingPlace.Remote, result);
}

Answer 2

Create a startup.cs file then map the dbcontext and the irepositoryDB specification to RepositoryDB concrete class. Dependency inject the IrepositoryDB in the xunit class constructor.
namespace XUnitTestProject1
{
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
var configuration = new ConfigurationBuilder()
.SetBasePath(System.IO.Directory.GetCurrentDirectory())
.AddJsonFile("appsettings.Development.json", false, true)
.Build();
services.AddControllers();
var connectionString = configuration.GetConnectionString("My_DbCoreConnectionString");
services.AddDbContext<MY_DB_Context>(options2 => options2.UseSqlServer(connectionString));
services.AddTransient<IRepositoryDB, RepositoryDB>();
}
}
}
XUnit
public class UnitTest1
{
private readonly IRepositoryDB _repository;
public UnitTest1(IRepositoryDB repository)
{
_repository = repository;
}
public async Task GetItems(long id)
{
IList<myItem> list= await _repository.GetItems(id);
Assert.True(list.Count>0);
}