爲什麼不使用AutoFixture Freeze，SemanticComparison Likeness和CreateProxy進行簡單測試？

Question

我想了解如何使用Likeness<T>()的CreateProxy()功能使用兩個簡單類的實例。

public class Band 
{ 
    public string Strings { get; set; } 
    public string Brass { get; set; } 
} 

具有以下測試中，我用一個Fixture到Create<T>一個Band實例與兩個字符串屬性的值。

[Fact] 
public void Equality_Behaves_As_Expected() 
{ 
    // arrange 
    var fixture = new Fixture(); 
    fixture.Customize(new AutoMoqCustomization()); 

    var original = fixture.Create<Band>(); 
    // Brass something like --> "Brass65756b89-d9f3-42f8-88fc-ab6de5ae65cd" 
    // Strings something like --> "Strings7439fa1b-014d-4544-8428-baea66858940" 

    // act 
    var dupe = new Band {Brass = original.Brass, 
         Strings = original.Strings}; 
    // Brass same as original's like --> "Brass65756b89-d9f3-42f8-88fc-ab6de5ae65cd" 
    // Strings same as original's like --> "Strings7439fa1b-014d-4544-8428-baea66858940" 

我已經嘗試了很多不同的說法，但問題的關鍵似乎是，該CreateProxy方法不填充的Band的性質，因此，即使當我嘗試兩個實例與比較Band相同的屬性值，CreateProxy方法的實例始終爲空值。

// assert 
    var likeness = dupe.AsSource().OfLikeness<Band>() 
         .Without(x => x.Brass).CreateProxy(); 
    // Brass & String properties are null using dupe as source of likeness (!) 

    //var likeness = original.AsSource().OfLikeness<Band>() 
    //      .Without(x => x.Brass).CreateProxy(); 
    // Brass & String properties are null using original as source of likeness (!) 

    //Assert.True(likeness.Equals(original)); // Fails 
    //Assert.True(original.Equals(likeness)); // Fails 

    // below are using FluentAssertions assembly 
    //likeness.Should().Be(original);   // Fails (null properties) 
    //original.Should().Be(likeness);   // Fails (null properties) 
    //likeness.ShouldBeEquivalentTo(original); // Fails (null properties) 
    //original.ShouldBeEquivalentTo(likeness); // Fails (null properties) 
} 

我得做一些錯的，但我讀過的一切，我可以找到Ploeh博客等，以及我在做什麼不能找到合適的很簡單的比較爲例。有任何想法嗎？

Answer 1

如果分配在代理實例的值（調用CreateProxy方法後）測試通過：

[Fact] 
public void Equality_Behaves_As_Expected() 
{ 
    // AutoMoqCustomization is not necessary. 
    var original = new Fixture().Create<Band>(); 

    var likeness = original 
     .AsSource() 
     .OfLikeness<Band>() 
     .Without(x => x.Brass) 
     .CreateProxy(); 

    likeness.Brass = "foo"; // Ignored. 
    likeness.Strings = original.Strings; 

    Assert.True(likeness.Equals(original)); 
    likeness.Should().Be(original); 
    likeness.ShouldBeEquivalentTo(original); 
} 

記住Likeness創建於目標類型，只有該類型的實例的代理重寫Equals。

由於源型保持不變，以下斷言將不會成功：

Assert.True(original.Equals(likeness));
original.Should().Be(likeness);
original.ShouldBeEquivalentTo(likeness);

更新

從3.0.4版本及以上值自動複製到代理實例（w這意味着，likeness.Strings = original.Strings;將自動發生）。