c# – 如何单元测试使用Entity Framework的存储库模式？

我正在尝试单元测试通过实体框架进行的存储库：

我想要发生的是测试存储库而不实际发送/连接到实际的数据库,我想这样做,而不使用任何嘲笑的框架.

目前我的测试是将数据发送到数据库,我想要发生的是测试add / remove等方法,而不会将实际数据发送到数据库,因为它仅用于测试.

这是存储库：

namespace AbstractFactory.Repository
{
    using System.Collections.Generic;
    using System.Data.Entity;
    using System.Linq;

    /// <summary>
    /// This class serves as the structure of the Author repository using a database
    /// </summary>
    public class DbAuthorRepository : IRepository<AuthorEntity>
    {

        private AbstractFactoryPatternEntities context;

        public DbAuthorRepository(AbstractFactoryPatternEntities context)
        {
            this.context = context;
        }

        /// <summary>
        /// Adds the specified author.
        /// </summary>
        /// <param name="author">The author.</param>
        public void Add(AuthorEntity author)
        {
            context.AuthorEntities.Add(author);
        }

        /// <summary>
        /// Removes the specified author.
        /// </summary>
        /// <param name="author">The author.</param>
        public void Remove(AuthorEntity author)
        {
            this.context.AuthorEntities.Remove(author);
        }

        /// <summary>
        /// Saves this instance.
        /// </summary>
        public void Save()
        {
            this.context.SaveChanges();
        }

        /// <summary>
        /// Gets all.
        /// </summary>
        /// <returns>returns a list of all the authors</returns>
        public IEnumerable<AuthorEntity> GetAll()
        {
            List<AuthorEntity> result = this.context.AuthorEntities.Include(a => a.Books).ToList();

            return result;
        }

        /// <summary>
        /// Gets the author by id.
        /// </summary>
        /// <param name="id">The id.</param>
        /// <returns>returns an entity</returns>
        public AuthorEntity GetById(int id)
        {
            AuthorEntity result = this.context.AuthorEntities.Single(a => a.AuthorId == id);

            return result;
        }
    }
}

以下是单元测试的当前代码：

[TestMethod]
        public void Add_MethodisCalled_EntityCountIsIncrementedByOne()
        {
            using (ShimsContext.Create())
            {
                ShimAbstractFactoryPatternEntities context = new ShimAbstractFactoryPatternEntities(new AbstractFactoryPatternEntities());
                DbAuthorRepository repository = new DbAuthorRepository(context);
                repository.Add(new AuthorEntity { FirstName = "Test",LastName = "testing=" });
                var actual = repository.GetAll().Count();
                repository.Save();
                var expected = repository.GetAll().Count();
                Assert.AreNotEqual(actual,expected);
            }

            //AbstractFactoryPatternEntities context = new AbstractFactoryPatternEntities();
            //DbAuthorRepository repository = new DbAuthorRepository(context);
            //var actual = repository.GetAll().Count();
            //repository.Add(new AuthorEntity { FirstName = "Testing",LastName = "MyTest" });
            //repository.Save();
            //var expected = repository.GetAll().Count();
            //Assert.AreNotEqual(actual,expected);
        }

        [TestMethod]
        public void Remove_MethodisCalled_EntityCountRemainsTheSame()
        {
            AbstractFactoryPatternEntities context = new AbstractFactoryPatternEntities();
            DbAuthorRepository repository = new DbAuthorRepository(context);
            AuthorEntity newAuthor = new AuthorEntity { FirstName = "Testing",LastName = "MyTest" };
            repository.Add(newAuthor);
            repository.Save();
            var actual = repository.GetAll().Count();
            Console.WriteLine(actual);
            repository.Remove(newAuthor);
            var expected = repository.GetAll().Count();
            Console.WriteLine(expected);
            Assert.AreEqual(actual,expected);
        }

        [TestMethod]
        public void Get_MethodisCalled_CorrectAuthorIsRetrieved()
        {
            AbstractFactoryPatternEntities context = new AbstractFactoryPatternEntities();
            DbAuthorRepository repository = new DbAuthorRepository(context);
            int target = 4;
            AuthorEntity author = repository.GetById(target);
            Assert.AreEqual(target,author.AuthorId);
        }

我想使用垫片/存根/假货来进行测试.

解决方法

实体框架存储库是您的存储库接口的具体实现.因为它是具体的,你不能抽象和测试没有数据库 – 这一具体实现的全部要写数据到数据库！

这意味着,测试EF存储库应该是旨在验证存储库写入实际数据库 – 在您调用存储库方法的测试的行为阶段,在断言阶段,您可以使用从数据库获取数据的任何其他方式(ado.net也许？)来检查存储库是否完成其工作.

另一个无关紧要的是,您可以使用存储库的另一个实现,该存储库使用内存中的数据存储,并将这些内存中的存储库注入到其他服务中,可以在不写入物理数据库的情况下测试这些服务.您甚至可以模拟一个注册到其他服务的存储库,只是为了执行一些行为测试,即测试您的服务是否正确使用您的存储库.

原文地址：https://www.jb51.cc/csharp/96875.html