用SaveChanges上发生的验证来模拟EF6

我找到了一篇体面的文章，让我开始使用Moq对基于实体框架的应用程序进行单元测试:https://msdn.microsoft.com/en-us/data/dn314429.aspx

我遇到的问题是Mock的SaveChanges方法似乎不像通常那样触发ValidateEntity方法。我在EntityTypeConfiguration中配置的所有验证设置都没有作为DbEntityValidationException抛出。

例如，我的AddRoles_Fails_For_Empty_Name测试以确保服务不能添加具有空名称的角色。要么没有应用IsRequired()配置，要么没有调用ValidateEntity方法。我应该提到，如果我在web应用程序中使用实际上下文，它会正确工作。

我在下面包含了一些相关的单元测试、DbContext和Service代码。

我做错了什么吗?是否有任何已知的问题或解决方法?

Role DB Map

public class RoleMap : EntityTypeConfiguration<Role>
{
    public RoleMap()
    {
        ToTable("bm_Roles");
        HasKey(r => r.Id);
        Property(r => r.Name).IsRequired().HasMaxLength(100).HasIndex(new IndexAttribute("UX_Role_Name") { IsUnique = true });
        Property(r => r.Description).HasMaxLength(500);
    }
}

DbContext

public class BlueMoonContext : DbContext, IBlueMoonContext
{
    public BlueMoonContext() : base("name=BlueMoon")
    {
    }
    public DbSet<Role> Roles { get; set; }
    public DbSet<User> Users { get; set; }
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);
        modelBuilder.Configurations.AddFromAssembly(typeof(BlueMoonContext).Assembly);
    }
    public void MarkAsModified<T>(T entity) where T : class
    {
        entity.ThrowIfNull("entity");
        Entry<T>(entity).State = EntityState.Modified;
    }
    protected override DbEntityValidationResult ValidateEntity(DbEntityEntry entityEntry, IDictionary<object, object> items)
    {
        var result = base.ValidateEntity(entityEntry, items);
        if (entityEntry.State == EntityState.Added || entityEntry.State == EntityState.Modified)
        {
            // Perform validations that require database lookups
            if (entityEntry.Entity is Role)
            {
                ValidateRole((Role)entityEntry.Entity, result);
            }
            else if (entityEntry.Entity is User)
            {
                ValidateUser((User)entityEntry.Entity, result);                    
            }
        }
        return result;
    }
    private void ValidateRole(Role role, DbEntityValidationResult result)
    {
        if (role.Name.HasValue() && !Roles.NameAvailable(role.Name, role.Id))
        {
            result.ValidationErrors.Add(new DbValidationError("Name", "Already in use"));
        }
    }
    private void ValidateUser(User user, DbEntityValidationResult result)
    {
        if (user.UserName.HasValue() && !Users.UserNameAvailable(user.UserName, user.Id))
        {
            result.ValidationErrors.Add(new DbValidationError("UserName", "Already in use"));
        }
        if (user.Email.HasValue() && !Users.UserNameAvailable(user.UserName, user.Id))
        {
            result.ValidationErrors.Add(new DbValidationError("Email", "Already in use"));
        }
    }
}

public class AccountService : BaseService, IAccountService
{
    private IPasswordHasher _passwordHasher;
    public AccountService(IBlueMoonContext context, IPasswordHasher passwordHasher) : base(context)
    {
        _passwordHasher = passwordHasher;
    }
    public ServiceResult CreateRole(Role role)
    {
        role.ThrowIfNull("role");
        Context.Roles.Add(role);
        return Save();
    }
    // Copied from base service class
    protected ServiceResult Save()
    {
        var result = new ServiceResult();
        try
        {
            Context.SaveChanges();
        }
        catch (DbEntityValidationException validationException)
        {
            foreach (var validationError in validationException.EntityValidationErrors)
            {
                foreach (var error in validationError.ValidationErrors)
                {
                    result.AddError(error.ErrorMessage, error.PropertyName);
                }
            }
        }
        return result;
    }
}

[TestFixture]
public class AccountServiceTests : BaseTest
{
    protected Mock<MockBlueMoonContext> _context;
    private IAccountService _accountService;
    [TestFixtureSetUp]
    public void Setup()
    {
        _context = new Mock<BlueMoonContext>();
        var data = new List<Role>
        {
            new Role { Id = 1, Name = "Super Admin" },
            new Role { Id = 2, Name = "Catalog Admin" },
            new Role { Id = 3, Name = "Order Admin" }
        }.AsQueryable();
        var roleSet = CreateMockSet<Role>(data);
        roleSet.Setup(m => m.Find(It.IsAny<object[]>())).Returns<object[]>(ids => data.FirstOrDefault(d => d.Id == (int)ids[0]));
        _context.Setup(m => m.Roles).Returns(roleSet.Object);
        // _context.Setup(m => m.SaveChanges()).Returns(0);
        _accountService = new AccountService(_context.Object, new CryptoPasswordHasher());
    }
    [Test]
    public void AddRole_Fails_For_Empty_Name()
    {
        var role = new Role { Id = 4, Name = "" };
        var result = _accountService.CreateRole(role);
        Assert.False(result.Success);
    }
}