Incorrect configuration for a non-virtual participant - on the interface?

Question

During unit testing using Moq, I get the following error:

Message: System.NotSupportedException : 
    Invalid setup on non-virtual (overridable in VB) member: 
    cm => cm.AppSettings[It.IsAny<string>()]

In these conclusions, I understand that it is preferable to use abstract classes or interfaces with Moq.

• Why should the property I want to make fun of be virtual?
• Moq throws wrong setting for uncaught member when class is in Service Project
• Incorrect setting for a non-virtual (redefined in VB) member
• Moq: invalid setting for uncaught member: x => x.GetByTitle ("asdf")

In short, I did my homework. =)

But what if I really use the interface?

ConfigurationServiceTests

[TestFixture]
public class ConfigurationServiceTests {
    [Test]
    public void DialectShouldQueryConfigurationManagerAppSettings() {
        // Given
        configurationManagerMock
            .Setup(cm => cm.AppSettings[It.IsAny<string>()])
            .Returns(It.IsAny<string>());

        // When
        var dialect = configurationService.Dialect;

        // Then
        dialect.Should().BeOfType<string>();
        configurationManagerMock.Verify(cm => cm.AppSettings[It.IsAny<string>()]);
    }

    [SetUp]
    public void ConfigurationServiceSetUp() {
        configurationManagerMock = new Mock<IConfigurationManager>();
        configurationService = 
            new ConfigurationService(configurationManagerMock.Object);
    }

    private Mock<IConfigurationManager> configurationManagerMock;
    private IConfigurationService configurationService;
}

IConfigurationManager

public interface IConfigurationManager {
    NameValueCollection AppSettings { get; }
    ConnectionStringSettingsCollection ConnectionStrings { get; }
}

IConfigurationService

public interface IConfigurationService {
    string ConnectionDriver { get; }
    string ConnectiongString { get; }
    string Dialect { get; }
}

ConfigurationService

public class ConfigurationService : IConfigurationService {
    public ConfigurationService(IConfigurationManager configurationManager) {
        this.configurationManager = configurationManager;
    }

    public string ConnectionDriver {
        get { return configurationManager.AppSettings["ConnectionDriver"]; }
    }

    public string ConnectionString {
        get { 
            return configurationManager
                .ConnectionStrings[ConnectionStringKey]
                .ConnectionString; 
        }
    }

    public string Dialect { 
        get { return configurationManager.AppSettings[DialectKey]; } 
    }

    private readonly IConfigurationManager configurationManager;

    private const string ConnectionStringKey = "DefaultConnectionString";
    private const string DialectKey = "Dialect";
}

Why did I create an interface IConfigurationManager?

• Configuration Manager

Ninject . , .

kernel.Bind<IConfiguration>().To<ConfigurationManager>().InSingletonScope();

unit test my ConfigurationService.

?

Answer 1

NameValueCollection .

- ( SetupGet Setup):

  .SetupGet(cm => cm.AppSettings).Returns(....)

, "" "- ", (, ).

, - Mock :

 configurationManagerMock  
   .SetupGet(cm => cm.AppSettings)
   .Returns(new NameValueCollection { {"SettingName", "Value"}});

- - IDictionary<string,string>, :

interface IConfigurationManager 
{
   IDictionary<string,string> AppSettings { get; }
   ...