c# - 单元测试重构

Question

我在为业务逻辑层编写单元测试时遇到了一些问题，请为我指出正确的方向。任何意见，将不胜感激。

业务逻辑

public class TitleLogic
{
    private readonly TitleDAL titleDAL = new TitleDAL();
    private readonly List<TitleEntity> titleEntities;

    public TitleLogic()
    {
        titleEntities = titleDAL.GetAllTitles().ToList();
    }

    public TitleEntity InsertTitle(TitleEntity titleEntity)
    {
        if (!titleEntity.IsValid)
        {
            throw new EntityException<TitleEntity>("Invalid Title.", titleEntity);
        }

        titleEntity.TitleName.TrimSize(TitleEntity.TitleName_Length);

        var createdTitle = titleDAL.InsertTitle(titleEntity);

        titleEntities.Add(createdTitle);

        return createdTitle;
    }

    public TitleEntity FindTitle(string titleName)
    {
        return titleEntities.Find(p => p.TitleName == titleName);
    }
}

数据层

public class TitleDAL
{
    private readonly NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger();

    public TitleEntity InsertTitle(TitleEntity titleEntity)
    {
        XTime900Entities xTime900Entities = new XTime900Entities();

        //Find the next CodeId to use
        var titleCodeId = xTime900Entities.TITLEs.Max(p => p.TITLE_CODEID) + 1;

        TITLE title = new TITLE
        {
            TITLE_CODEID = (short) titleCodeId,
            TITLE_ACTIVE = Convert.ToInt16(titleEntity.TitleActive),
            TITLE_NAME = titleEntity.TitleName
        };

        xTime900Entities.TITLEs.InsertOnSubmit(title);
        xTime900Entities.SubmitChanges();
        logger.Debug("Inserted New Title CodeId: {0}", titleCodeId);
        xTime900Entities.Dispose();

        return titleEntity.Clone((short)titleCodeId);
    }

    public ICollection<TitleEntity> GetAllTitles()
    {
        logger.Debug("Retrieving List all Titles from XTime900 database.");
        List<TitleEntity> titleEntities = new List<TitleEntity>();

        using (XTime900Entities XTEntities = new XTime900Entities())
        {
            var titlesInDB = from p in XTEntities.TITLEs
                                  select p;

            foreach (var titlesInDb in titlesInDB)
            {
                TitleEntity genderEntity = new TitleEntity(titlesInDb.TITLE_CODEID)
                {
                    TitleActive = Convert.ToBoolean(titlesInDb.TITLE_ACTIVE),
                    TitleName = titlesInDb.TITLE_NAME
                };

                titleEntities.Add(genderEntity);
            }
        }

        logger.Debug("Found {0} Titles.", titleEntities.Count);
        return titleEntities;
    }
}

实体

public class TitleEntity
{
    public const int TitleName_Length = 30;

    public short TitleCodeId { get; private set; }
    public bool TitleActive { get; set; }
    public string TitleName { get; set; }
    public bool IsValid
    {
        get
        {
            return !String.IsNullOrEmpty(TitleName);
        }
    }

    public TitleEntity()
    {
        this.TitleCodeId = -1;
    }
    public TitleEntity(short titleCodeId)
    {
        this.TitleCodeId = titleCodeId;
    }

    public TitleEntity Clone(short titleCodeId)
    {
        TitleEntity genderEntity = new TitleEntity(titleCodeId)
        {
            TitleActive = this.TitleActive,
            TitleName = this.TitleName
        };

        return genderEntity;
    }

    public override string ToString()
    {
        StringBuilder sb = new StringBuilder();
        sb.AppendLine(String.Format("TitleCodeId : {0}", TitleCodeId));
        sb.AppendLine(String.Format("TitleActive : {0}", TitleActive));
        sb.AppendLine(String.Format("TitleName : {0}", TitleName));
        return sb.ToString();
    }

    public static bool operator ==(TitleEntity x, TitleEntity y)
    {
        return (x.Equals(y));
    }

    public static bool operator !=(TitleEntity x, TitleEntity y)
    {
        return !(x.Equals(y));
    }

    public bool Equals(TitleEntity other)
    {
        if (ReferenceEquals(null, other)) return false;
        if (ReferenceEquals(this, other)) return true;
        return other.TitleCodeId == TitleCodeId && other.TitleActive.Equals(TitleActive) && Equals(other.TitleName, TitleName);
    }

    public override bool Equals(object obj)
    {
        if (ReferenceEquals(null, obj)) return false;
        if (ReferenceEquals(this, obj)) return true;
        return obj.GetType() == typeof(TitleEntity) && Equals((TitleEntity)obj);
    }

    public override int GetHashCode()
    {
        unchecked
        {
            var result = TitleCodeId.GetHashCode();
            result = (result * 397) ^ TitleActive.GetHashCode();
            result = (result * 397) ^ (TitleName != null ? TitleName.GetHashCode() : 0);
            return result;
        }
    }
}

Answer 1

您无法轻松测试您的业务逻辑，因为您已经在 TitleLogic 中创建了 DAL 组件。类。

我要做的第一件事就是制作 TitleDAL实现 ITitleDAL接口(interface)和制作 TitleLogic类采用 ITitleDAL 的实例界面。

然后当您测试InsertTitle时您可以通过以下方法进行测试:

• 检查当 TitleEntity 无效时给出 EntityException被抛出
• 当实体有效时 ITitleDAL.InsertTitle被称为。
• 正确插入标题后，可以使用FindTitle找到它。方法

在您的测试中，您需要创建一个模拟 ITitleDAL实现(或使用 mocking library 为您创建一个)，以便您的测试返回已知的预期数据，而不依赖于实际的 DAL。

您可能还想考虑测试:

• 如果InsertTitle会发生什么方法ITitleDAL失败？