测试工厂模式

Question

我有小样本工厂模式实现的下方,并想知道如果有人可以帮我写正确的起订量的单元测试用例,最大代码覆盖率:

public class TestClass
{ 
    private readonly IService service;

    public TestClass(Iservice service)
    {
        this.service = service;
    }

    public void Method(string test)
    {
        service = TestMethod(test);
        service.somemethod();
    }

    private IService TestMethod(string test)
    {
        if(test == 'A')
            service = new A();
        if(test == 'B')
            service = new B();
        return service;
    }
}

我正在寻找测试TestClass的一些帮助,更重要的是我发送Mock时的TestMethod,例如我的测试方法如下:

[TestMethod]
public void TestCaseA()
{
    Mock<IService> serviceMock = new Mock<Iservice>(MockBehaviour.strict);
    TestClass tClass = new TestClass(serviceMock.Object);

    // The Question is, what is best approach to test this scenario ?
    // If i go with below approach, new A() will override serviceMock
    // which i am passing through constructor.
    var target = tClass.Method("A");
}

Answer 1

你不会嘲笑TestClass,因为那是你正在测试的.

为此,您需要为其创建只读属性service.

public IService Service { get; private set; }

您需要测试构造函数的方式并Method修改实例的状态(在本例中Service)TestClass.

您的测试将类似于用于测试下面Method的B测试案例:

[TestMethod]
public void TestSomeMethod()
{
    // Arrange/Act
    var target = new TestClass((new Mock<IService>()).Object);
    target.Method("B");

    // Assert
    Assert.IsInstanceOfType(target.Service, typeof(B));
}

为测试测试用例的构造函数,您的测试看起来类似于以下内容A:

[TestMethod()]
public void TestCasesA()
{
    // Arrange/Act
    var target = new TestClass("A");

    // Assert
    Assert.IsInstanceOfType(target.service, typeof(A));
}

我建议只使用构造函数方法来注入你的IService.这允许您拥有一个不可变对象,这将减少您的应用程序的状态.