模拟AsNoTracking实体框架

问题描述

我如何嘲笑AsNoTracking方法？结果在下面的例子中，已经的DbContext注入，如果我remove从GetOrderedProducts方法AsNoTracking扩展方法class.It工作正常服务，但由于AsNoTracking返回null测试失败。
我还试图嘲弄AsNoTracking返回正确的值，但没有奏效。

How do I mock AsNoTracking method?
In below example, DbContext has injected to the service class.It works fine if I remove AsNoTracking extension method from GetOrderedProducts method, but with AsNoTracking test fails because it returns null.I've also tried to mock AsNoTracking to return proper value but it didn't work.

public interface IUnitOfWork
{
    IDbSet<TEntity> Set<TEntity>() where TEntity : class;
    int SaveAllChanges();
}

public class Entites : DbContext, IUnitOfWork
{
    public virtual DbSet<Product> Products { get; set; }  // This is virtual because Moq needs to override the behaviour

    public new virtual IDbSet<TEntity> Set<TEntity>() where TEntity : class   // This is virtual because Moq needs to override the behaviour
    {
        return base.Set<TEntity>();
    }

    public int SaveAllChanges()
    {
        return base.SaveChanges();
    }
}

    public class ProductService
{
    private readonly IDbSet<Product> _products;
    private readonly IUnitOfWork _uow;

    public ProductService(IUnitOfWork uow)
    {
        _uow = uow;
        _products = _uow.Set<Product>();
    }
    public IEnumerable<Product> GetOrderedProducts()
    {
        return _products.AsNoTracking().OrderBy(x => x.Name).ToList();
    }
}

    [TestFixture]
public class ProductServiceTest
{
    private readonly ProductService _productService;

    public ProductServiceTest()
    {
        IQueryable<Product> data = GetRoadNetworks().AsQueryable();
        var mockSet = new Mock<DbSet<Product>>();
        mockSet.As<IQueryable<Product>>().Setup(m => m.Provider).Returns(data.Provider);
        mockSet.As<IQueryable<Product>>().Setup(m => m.Expression).Returns(data.Expression);
        mockSet.As<IQueryable<Product>>().Setup(m => m.ElementType).Returns(data.ElementType);
        mockSet.As<IQueryable<Product>>().Setup(m => m.GetEnumerator()).Returns(data.GetEnumerator());
        var context = new Mock<Entites>();
        context.Setup(c => c.Products).Returns(mockSet.Object);
        context.Setup(m => m.Set<Product>()).Returns(mockSet.Object);
        context.Setup(c => c.Products.AsNoTracking()).Returns(mockSet.Object);
        _productService = new ProductService(context.Object);
    }

    private IEnumerable<Product> GetRoadNetworks()
    {
        return new List<Product>
        {
            new Product
            {
                Id = 1,
                Name = "A"
            },
            new Product
            {
                Id = 2,
                Name = "B"
            },
            new Product
            {
                Id = 1,
                Name = "C"
            }
        };
    }

    [Test]
    public void GetOrderedProductTest()
    {
        IEnumerable<Product> products = _productService.GetOrderedProducts();
        List<string> names = products.Select(x => x.Name).ToList();
        var expected = new List<string> {"A", "B", "C"};
        CollectionAssert.AreEqual(names, expected);
    }
}

问题是AsNoTracking返回空单元测试

The problem is AsNoTracking returns null in unit test

推荐答案

综观的中的 AsNoTracking（）扩展方法：

public static IQueryable AsNoTracking(this IQueryable source)
{
    var asDbQuery = source as DbQuery;
    return asDbQuery != null ? asDbQuery.AsNoTracking() : CommonAsNoTracking(source);
}

由于源（你的 DbSet<产品> 你试图嘲弄）确实是一个的DBQuery （因为 DbSet 是的DBQuery ），它试图调用真实（非轻慢） AsNoTracking（）派生方法，它理所当然地返回null。

Since source (your DbSet<Product> you're trying to mock) is indeed a DbQuery (because DbSet is deriving from DbQuery), it tries to invoke the 'real' (non-mocked) AsNoTracking() method which rightfully returns null.

尝试嘲笑 AsNoTracking（）方法，以及：

mockSet.Setup(x => x.AsNoTracking()).Returns(mockSet.Object);

这篇关于模拟AsNoTracking实体框架的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！