使用基础 class 进行集成测试

Question

我的基础 class 集成测试：

[TestClass]
public class BaseIntegrationTest
{
    protected readonly ApplicationDbContext _dbContext;

    public BaseIntegrationTest()
    {
        _dbContext = new ApplicationDbContext("DefaultConnectionTest");
    }

    [ClassInitialize]
    public void Initialize()
    {
        InsertTestData();
    }

    public void InsertTestData()
    {
        _dbContext.Users.Add(new User { Name = "John Doe" });
    }
}

这是一个继承自 BaseIntegrationTest 的测试 class：

[TestClass]
public class UserRepositoryTests : BaseIntegrationTest
{
    // how to lose this method here and use the one in the BaseIntegrationTest?
    //[ClassInitialize]
    //public static void Setup(TestContext context)
    //{
    //  BaseIntegrationTest test = new BaseIntegrationTest();
    //  test.InsertTestData();
    //}

    [TestMethod]
    public void GetUser()
    {
        Filter f = new Filter()
        {
            Name = "John Doe"
        };

        UserRepository fr = new UserRepository(_dbContext);
        var result = fr.GetUser(f);

        Assert.IsTrue(result.Any(x => x.Name == "John Doe"));
    }
}

BaseIntegrationTest 中用 [ClassInitialize] 属性修饰的方法永远不会执行，因此，我的测试失败了。没有数据被插入到数据库中。

但是如果我取消注释 UserRepositoryTests 中的 public static void Setup(TestContext context) 它会起作用。

我还有几个要测试的存储库。我希望将数据插入到数据库中并在基础 class 中完成，这样我就可以运行所有测试，而无需为我要测试的每个存储库重新创建数据库。

将public void Initialize()转换为public static void Initialize(TestContext context)也不起作用。 Initialize() 不会得到 executed/called。

我错过了什么吗？还是单元 test/integration 测试的这些限制？我对单元 testing/integration 测试还很陌生。

Answer 1

来自 MSDN：

Will the same approach that was used for [TestInitialize] work with [ClassInitialize] in a base class?

Not exactly, if you create a [ClassInitialize] attributed method in the base class it won’t ever get called unless you explicitly call it at the beginning of your derived test classes ClassInitialize method; which of course is nowhere near as nice as the above approach.

http://blogs.msdn.com/b/densto/archive/2008/05/16/using-a-base-class-for-your-unit-test-classes.aspx

稍后介绍如何在继承任何方法之前进行初始化class:

How can I create an initialization method that will run before any class initialization methods in my test project?

Building on the common base class approach described above you could simply add a static constructor to your base class and either perform the initialization there or call the method that will perform the desired initialization. The resulting base class might look like this:

[TestClass]
public class TestBase
{
    static TestBase()
    {
        s_log = new StringBuilder();
        Log.AppendLine("TestBase.ctor()");
    }

    [TestInitialize]
    public void BaseTestInit()
    {
        Log.AppendLine("TestBase.BaseTestInit()");
    }

    [TestCleanup]
    public void BaseTestCleanup()
    {
        Console.WriteLine(Log.ToString());
    }

    public static StringBuilder Log
    {
        get { return s_log; }
    }

    static StringBuilder s_log;
}

Answer 2

虽然此模式适用于 nunit，但似乎不适用于 mstest，因为无法继承 ClassInitializeAttribute。

一种变通方法是在基础的构造函数中进行初始化 class。

类似于：

[TestClass]
public class BaseIntegrationTest
{
    protected readonly ApplicationDbContext _dbContext;

    public BaseIntegrationTest()
    {
        _dbContext = new ApplicationDbContext("DefaultConnectionTest");
         InsertTestData();
    }

    public void InsertTestData()
    {
        _dbContext.Users.Add(new User { Name = "John Doe" });
    }
}

您可以添加一个静态标志来防止它运行每次测试：

[TestClass]
public class BaseIntegrationTest
{
    private static bool _testsInitialized = false;

    protected readonly ApplicationDbContext _dbContext;

    public BaseIntegrationTest()
    {
        if(!_testsInitialized) {
            _dbContext = new ApplicationDbContext("DefaultConnectionTest");
             InsertTestData();
            _testsInitialized = true;
        }
    }

    public void InsertTestData()
    {
        _dbContext.Users.Add(new User { Name = "John Doe" });
    }
}

..相当不优雅，但可能比将 ApplicationDbContext 设为静态（以及从静态 ctor 调用的所有其他方法）更优雅

使用基础 class 进行集成测试

Using a base class for an integration test

c#

unit-testing

integration-testing