c# - 防止 Autofixture 填充子集合

Question

我正在使用最新版本的 Autofixture，我想阻止它自动填充子集合。

例如，我有一个具有 List 属性的类 Person。我想要填充所有属性，但列表除外。

我试过使用这个定制:

public class RemoveMultiples : ICustomization
{
    public void Customize(IFixture fixture)
    {
        fixture.Customizations
            .OfType<FilteringSpecimenBuilder>()
            .Where(x => x.Specification is DictionarySpecification)
            .ToList().ForEach(c => fixture.Customizations.Remove(c));
        fixture.Customizations
            .OfType<FilteringSpecimenBuilder>()
            .Where(x => x.Specification is CollectionSpecification)
            .ToList().ForEach(c => fixture.Customizations.Remove(c));
        fixture.Customizations
            .OfType<FilteringSpecimenBuilder>()
            .Where(x => x.Specification is HashSetSpecification)
            .ToList().ForEach(c => fixture.Customizations.Remove(c));
        fixture.Customizations
            .OfType<FilteringSpecimenBuilder>()
            .Where(x => x.Specification is ListSpecification)
            .ToList().ForEach(c => fixture.Customizations.Remove(c));
    }
}

但它也阻止我使用 .CreateMany()。

编辑:我可以使用 .CreateMany(3) 并且它有效。

有什么设置可以让我只在需要时自动填充收藏吗？

edit2:类人应该是这样的:

[Serializable]
public class Person
{
    private ICollection<OtherClass> _otherClasses; 
    private string _something;
    public virtual ICollection<OtherClass> OtherClasses
    {
        get { return _otherClasses; }
        set { _otherClasses = value; }
    }
}

请注意，它并不总是一个Collection，有时是IList

注意 2:我刚刚意识到有人还删除了 IEnumerable 的自定义，因此 CreateMany() 没有创建任何东西。

Answer 1

这是一种方法。

首先实现一个 SpecimenBuilder，告诉 AutoFixture 跳过为集合属性赋值:

public class CollectionPropertyOmitter : ISpecimenBuilder
{
    public object Create(object request, ISpecimenContext context)
    {
        var pi = request as PropertyInfo;
        if (pi != null
            && pi.PropertyType.IsGenericType
            && pi.PropertyType.GetGenericTypeDefinition() == typeof(ICollection<>))
            return new OmitSpecimen();

        return new NoSpecimen(request);
    }
}

然后将其封装在自定义中:

public class DoNotFillCollectionProperties : ICustomization
{
    public void Customize(IFixture fixture)
    {
        fixture.Customizations.Add(new CollectionPropertyOmitter());
    }
}

现在通过了以下测试:

[Fact]
public void CreatePersonWithoutFillingCollectionProperty()
{
    var fixture = new Fixture().Customize(new DoNotFillCollectionProperties());
    var actual = fixture.Create<Person>();
    Assert.Null(actual.OtherClasses);
}

[Fact]
public void CreateManyStillWorks()
{
    var fixture = new Fixture().Customize(new DoNotFillCollectionProperties());
    var actual = fixture.CreateMany<Person>();
    Assert.NotEmpty(actual);
}

[Fact]
public void CreatListStillWorks()
{
    var fixture = new Fixture().Customize(new DoNotFillCollectionProperties());
    var actual = fixture.Create<List<Person>>();
    Assert.NotEmpty(actual);
}

[Fact]
public void CreateCollectionStillWorks()
{
    var fixture = new Fixture().Customize(new DoNotFillCollectionProperties());
    var actual = fixture.Create<ICollection<Person>>();
    Assert.NotEmpty(actual);
}