Question

我正在尝试通过编写一些简单的单元测试来学习Moq。其中一些与名为AppSettingsReader的类有关：

public class BackgroundCheckServiceAppSettingsReader : IBackgroundCheckServiceAppSettingsReader
{
    private string _someAppSetting;

    public BackgroundCheckServiceAppSettingsReader(IWorkHandlerConfigReader configReader) 
    {
        if (configReader.AppSettingsSection.Settings["SomeAppSetting"] != null)
            this._someAppSetting = configReader.AppSettingsSection.Settings["SomeAppSetting"].Value;
    }        

    public string SomeAppSetting
    {
        get { return _someAppSetting; }
    }
}

类的接口定义如下：

public interface IBackgroundCheckServiceAppSettingsReader
{
    string SomeAppSetting { get; }
}

IWorkHandlerConfigReader（我无权修改）的定义如下：

public interface IWorkHandlerConfigReader
{
    AppSettingsSection AppSettingsSection { get; }
    ConnectionStringsSection ConnectionStringsSection { get; }
    ConfigurationSectionCollection Sections { get; }

    ConfigurationSection GetSection(string sectionName);
}

当我编写单元测试时，我创建Mock的{{1}}并尝试设置预期的行为：

IWorkHandlerConfigReader

这是编译，但是当我运行测试时，我看到以下错误：//Arrange string expectedReturnValue = "This_is_from_the_app_settings"; var configReaderMock = new Mock<IWorkHandlerConfigReader>(); configReaderMock.Setup(cr => cr.AppSettingsSection.Settings["SomeAppSetting"].Value).Returns(expectedReturnValue); //Act var reader = new BackgroundCheckServiceAppSettingsReader(configReaderMock.Object); var result = reader.SomeAppSetting; //Assert Assert.Equal(expectedReturnValue, result);

除了Mock对象之外，还有其他方法可以解决这个问题吗？我误解了它应该如何使用？

Answer 1

您实际上是在询问AppSettingsSection实例的依赖关系。因此，您应该设置此属性getter以返回包含所需数据的部分实例：

// Arrange
string expectedReturnValue = "This_is_from_the_app_settings";
var appSettings = new AppSettingsSection(); 
appSettings.Settings.Add("SomeAppSetting", expectedReturnValue);

var configReaderMock = new Mock<IWorkHandlerConfigReader>();
configReaderMock.Setup(cr => cr.AppSettingsSection).Returns(appSettings);
var reader = new BackgroundCheckServiceAppSettingsReader(configReaderMock.Object);

// Act
var result = reader.SomeAppSetting;

// Assert
Assert.Equal(expectedReturnValue, result);

设置模拟配置读取器时出错

1 个答案: