始终使用AutoFixture,XUnit和Moq冻结模拟

Question

我正在使用AutoFixture,Moq和XUnit扩展([Theory]属性),如本博客文章http://blog.ploeh.dk/2010/10/08/AutoDataTheorieswithAutoFixture中所述.

我注意到大多数单元测试看起来像这样:

[Theory, AutoMoqData]
public void Test(
    [Frozen] Mock<IServiceOne> serviceOne,
    [Frozen] Mock<IServiceTwo> serviceTwo,

    MyClass classUnderTest)
{
    // Arrange
    serviceOne
        .Setup(m => m.Get(It.IsAny<int>()));

    serviceTwo
        .Setup(m => m.Delete(It.IsAny<int>()));

    // MyClass has a constructor with arguments for IServiceOne, and IServiceTwo
    // classUnderTest will use the two mocks specified above

    // Act
    var result = classUnderTest.Foo();

    // Assert
    Assert.True(result);
}

与总是装饰模具相反[Frozen],是否有办法设置夹具以始终冻结模具？

这是AutoMoqData属性:

public class AutoMoqDataAttribute : AutoDataAttribute
{
    public AutoMoqDataAttribute()
        : base(new Fixture().Customize(new AutoMoqCustomization()))
    {
    }
}

Answer 1

虽然它目前不是内置的,但是编写一个通用的装饰器很容易,当它们离开AutoFixture树的责任时冻结对象:

public class MemoizingBuilder : ISpecimenBuilder
{
    private readonly ISpecimenBuilder builder;
    private readonly ConcurrentDictionary<object, object> instances;

    public MemoizingBuilder(ISpecimenBuilder builder)
    {
        this.builder = builder;
        this.instances = new ConcurrentDictionary<object, object>();
    }

    public object Create(object request, ISpecimenContext context)
    {
        return this.instances.GetOrAdd(
            request,
            r => this.builder.Create(r, context));
    }
}

请注意,它装饰了另一个ISpecimenBuilder,但在返回之前记住所有值.如果同一请求再次到达,它将返回memoized值.

虽然你无法扩展 AutoMoqCustomization,但你可以复制它的作用(它只有两行代码),并使用它MemoizingBuilder周围:

public class AutoFreezeMoq : ICustomization
{
    public void Customize(IFixture fixture)
    {
        if (fixture == null)
            throw new ArgumentNullException("fixture");

        fixture.Customizations.Add(
            new MemoizingBuilder(
                new MockPostprocessor(
                    new MethodInvoker(
                        new MockConstructorQuery()))));
        fixture.ResidueCollectors.Add(new MockRelay());
    }
}

用它AutoFreezeMoq代替AutoMoqCustomization.它将冻结所有模拟,以及从这些模拟创建的所有接口和抽象基类.

public class AutoMoqDataAttribute : AutoDataAttribute
{
    public AutoMoqDataAttribute()
        : base(new Fixture().Customize(new AutoFreezeMoq()))
    {
    }
}