Question

结构：

DAL - 实体框架，通用存储库，工作单元
BLL - service，automapper（将实体生成的类/对象映射到业务对象）
接口 - iservice
模型 - 业务对象Web - mvc
测试 - 单元测试

通用存储库

public class EntityRepository<T> : IEntityRepository<T> where T : class
{
    internal MyDB_Entities context;
    internal DbSet<T> dbSet;

    public EntityRepository(MyDB_Entities context)
    {
        this.context = context;
        this.dbSet = context.Set<T>();
    }

    public virtual T GetByID(object id)
    {
        return dbSet.Find(id);
    }

    // more code
}

通用存储库的接口

public interface IEntityRepository<T> where T : class
{ 
    IEnumerable<T> Get(Expression<Func<T, bool>> filter = null, Func<IQueryable<T>, IOrderedQueryable<T>> orderBy = null, string includeProperties = "");
    T GetByID(object id);
    // more code
}

工作单元

public class UnitOfWork : IUnitOfWork, IDisposable
{
    MyDB_Entities _context;
    public IEntityRepository<Customer> customerRepository { get; set; }
    public IEntityRepository<Product> productRepository { get; set; }

    public UnitOfWork(MyDB_Entities context)
    {
        _context = context;
        customerRepository = new EntityRepository<Customer>(_context);
        productRepository = new EntityRepository<Product>(_context); 
    }

    public void Save()
    {
        _context.SaveChanges();
    }
    // more code
}

工作单位界面

public interface IUnitOfWork
{
    IEntityRepository<Customer> customerRepository { get; set; }
    IEntityRepository<Product> productRepository { get; set; }
    void Dispose();
    void Save();
}

服务

public class SomeService : ISomeService 
{
    readonly IUnitOfWork _unitOfWork;
    public SomeService (IUnitOfWork unitOfWork)
    {
        _unitOfWork = unitOfWork;
    }
    // DoSomethingMethod
}

服务界面

public interface ISomeService
{
    // IDoSomethingMethod 
}

扩展

public static class MockDBSetExtension
{
    public static void SetSource<T>(this Mock<DbSet<T>> mockSet, IList<T> source) where T : class
    {
        var data = source.AsQueryable();
        mockSet.As<IQueryable<T>>().Setup(m => m.Provider).Returns(data.Provider);
        mockSet.As<IQueryable<T>>().Setup(m => m.Expression).Returns(data.Expression);
        mockSet.As<IQueryable<T>>().Setup(m => m.ElementType).Returns(data.ElementType);
        mockSet.As<IQueryable<T>>().Setup(m => m.GetEnumerator()).Returns(data.GetEnumerator());
    }
}

测试类

[TestClass]
public class My_Test
{
    Mock<DbSet<Product>> _mockProductDBSet;
    Mock<MyDB_Entities> mockContext;

    [TestInitialize]
    public void TestInitialize()
    {
        _mockProductDBSet = new Mock<DbSet<Product>>();
        mockContext = new Mock<MyDB_Entities>();
        mockContext.Setup(s => s.Products).Returns(_mockProductDBSet.Object);
    }

    [TestMethod]
    public void TestMocking()
    {
       var prod = new Product() { ProductName= "AAA", ProductID = 1 };
        _mockProductDBSet.SetSource(new List<Product> { prod });
       // more code here (new up the service, then test the service method, etc)
    }
}

问题/问题

我无法通过测试，因为通用存储库类 this.dbSet = context.Set（）; 总是 null 。如您所见，我模拟了dbset和上下文。我还设置了模拟的上下文来返回模拟的DBSet。 EnityRepository构造函数按预期方式获取模拟上下文，但是 this.dbSet = context.Set（）; 不会拾取我的模拟DBSet。我不确定我做错了什么。我没有以正确的方式测试/嘲笑吗？

Answer 1

假设您将IProuctService定义为

public interface IProductService {
    string GetProductName(int productId);
}

具体实施取决于IUnitOfWork

public class ProductService : IProductService {
    readonly IUnitOfWork _unitOfWork;
    public ProductService(IUnitOfWork unitOfWork) {
        _unitOfWork = unitOfWork;
    }

    public string GetProductName(int productId) {
        var item = _unitOfWork.productRepository.GetByID(productId);

        if (item != null) {
            return item.ProductName;
        }

        throw new ArgumentException("Invalid product id");
    }
}

如果测试的方法是IProductService.GetProductName，这里有一个可以进行测试的例子。

[TestMethod]
public void ProductService_Given_Product_Id_Should_Get_Product_Name() {
    //Arrange
    var productId = 1;
    var expected = "AAA";
    var product = new Product() { ProductName = expected, ProductID = productId };

    var productRepositoryMock = new Mock<IEntityRepository<Product>>();
    productRepositoryMock.Setup(m => m.GetByID(productId)).Returns(product).Verifiable();

    var unitOfWorkMock = new Mock<IUnitOfWork>();
    unitOfWorkMock.Setup(m => m.productRepository).Returns(productRepositoryMock.Object);

    IProductService sut = new ProductService(unitOfWorkMock.Object);
    //Act
    var actual = sut.GetProductName(productId);

    //Assert
    productRepositoryMock.Verify();//verify that GetByID was called based on setup.
    Assert.IsNotNull(actual);//assert that a result was returned
    Assert.AreEqual(expected, actual);//assert that actual result was as expected
}

在这种情况下，不需要模拟DbSet或DbContext，因为SUT不需要依赖接口的实现。它们可以被模拟以供被测系统使用。

使用Moq的单元测试enity框架通用存储库

1 个答案: