c# – 在AutoFixture自定义上调用Dispose方法

我正在使用AutoFixture自定义来测试访问sql Compact DB的存储库.

测试完成后立即删除此数据库对我非常有帮助.因为db是在自定义构造函数中创建的,所以我认为删除它的最佳位置是dispose方法.

我想的代码是：

internal class ProjectRepositoryCustomization : ICustomization
{
    private readonly String _dbLocation;

    public ProjectRepositoryCustomization()
    {
        var tempDbLocation = Path.Combine(Path.GetTempPath(),"TempDbToDelete");
        if (!Directory.Exists(tempDbLocation))
        {
            Directory.CreateDirectory(tempDbLocation);
        }

        _dbLocation = Path.Combine(tempDbLocation,Guid.NewGuid().ToString("N") + ".sdf");
    }

    public void Customize(IFixture fixture)
    {   
        DataContextConfiguration.database = _dbLocation;

        var dataContextFactory = new BaseDataContextFactory();
        var projRepository = new ProjectRepository(dataContextFactory);
        fixture.Register(() => projRepository);
    }

    public void dispose()
    {
        if (File.Exists(_dbLocation))
        {
            File.Delete(_dbLocation);
        }
    }
}

有可能做类似的事情吗？

解决方法

正如@Ruben Bartelink在评论中指出的那样,这是有可能的.但是,我会推荐一种不同的方法,这就是原因.

管理对象的生命周期是您通常希望能够对IoC容器执行的操作.但是,AutoFixture虽然看起来像IoC容器,但它确实是not meant to be one：

AutoFixture shares a lot of similarities with DI Containers. It
supports auto-wiring and it can be configured to create instances in
lots of interesting ways. However,since the focus is different,it
does some things better and some things not as well as a DI Container.

AutoFixture的主要目标是在一些可配置的范围内轻松创建anonymous test data.它的API专注于允许程序员自定义测试数据的生成方式,而不是生成测试数据的时间,因为假设它只被消耗within the context of a test：

AutoFixture is weaker when it comes to lifetime
management. A Fixture is never expected to exist for more than a
single test case,so it makes no sense to model any other lifestyle
than Transient and Singleton. […] It doesn’t have
to,because it’s not a DI Container.

另一方面,测试框架非常擅长管理测试夹具的使用寿命.由于您所描述的内容通常是管理集成测试的上下文的一部分,因此我会在执行夹具中的所有测试之前和之后运行它.

例如：

[TestFixture]
public class WithDatabaseContext
{
    private string dbLocation;
    private BaseDataContextFactory dataContextFactory

    protected BaseDataContextFactory DataContextFactory
    {
        get { return this.dataContextFactory; }
    }

    [TestFixtureSetUp]
    public void FixtureInit()
    {
        // Initialize dbLocation
        // Initialize dataContextFactory
    }

    [TestFixtureTearDown]
    public void Fixturedispose()
    {
        // Delete file at dbLocation
    } 
}

然后,您的测试可以继承上下文并使用它来配置AutoFixture：

[TestFixture]
public void SomeTest : WithDatabaseContext
{
    private IFixture fixture;

    [SetUp]
    public void Init()
    {
        this.fixture = new Fixture();
        this.fixture.Register(
            () => new ProjectRepository(base.DataContextFactory));
    }

    [Test]
    public void Doing_something_should_return_something_else()
    {
        // ...
    }
}

在这种情况下,利用测试框架来管理临时数据库的生命周期,可以在测试环境中清楚地传达其边界.在我看来,将它隐藏在AutoFixture定制中会使它更不明显,并且可以说更难以使用.