I'm trying to learn Moq by writing some simple unit tests. Some of them have to do with a class called AppSettingsReader:
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; }
}
}
The interface for the class is defined like this:
public interface IBackgroundCheckServiceAppSettingsReader
{
string SomeAppSetting { get; }
}
And the IWorkHandlerConfigReader (which I do not have permission to modify) is defined like so:
public interface IWorkHandlerConfigReader
{
AppSettingsSection AppSettingsSection { get; }
ConnectionStringsSection ConnectionStringsSection { get; }
ConfigurationSectionCollection Sections { get; }
ConfigurationSection GetSection(string sectionName);
}
When I write the unit test, I create a Mock of the IWorkHandlerConfigReader and try to set up the expected behavior:
//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);
This compiles, but when I run the test, I see the following error: System.NotSupportedException : Invalid setup on a non-virtual (overridable in VB) member: cr => cr.AppSettingsSection.Settings["SomeAppSetting"].Value
Is there another way to approach this other than a Mock object? Am I misunderstanding how it should be used?
You are actually asking dependency for AppSettingsSection instance. So, you should setup this property getter to return some section instance with data you need:
// 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);
Related
I have a custom implementation of CodeAccessSecurityAttribute that is connecting external sources to do a validation.
[Serializable]
[AttributeUsage(AttributeTargets.Method)]
public class IsAuthorizedAttribute : CodeAccessSecurityAttribute
{
private static readonly PrincipalPermission Allowed = new PrincipalPermission(PermissionState.None);
private static readonly PrincipalPermission NotAllowed = new PrincipalPermission(PermissionState.Unrestricted);
public string EntityObject { get; set; }
public string Field { get; set; }
public char Expected { get; set; }
public IsAuthorizedAttribute(SecurityAction action)
: base(action)
{
//setup
}
public override IPermission CreatePermission()
{
return IsAuthorised(EntityObject, Field, Expected, ServicesConfiguration) ? Allowed : NotAllowed;
}
private static bool IsAuthorised(string entityObject, string field, char expected, ServicesConfiguration servicesConfiguration)
{
bool? response = null;
//check external stuff
return response ?? false;
}
}
I have decorated my methods with this attribute:
[IsAuthorized(SecurityAction.Demand, EntityObject = Fields.UserManagement, Field = Fields.AllowDisplay, Expected = '1')]
public List<Group> GetUserGroups()
{
var response = new List<Group>();
//Get the groups from the database
var groups = groupManager.FindAll();
//Map them to the output group type
response = groups.Select(x => new Group()
{
ID = x.ID,
Name = x.Name,
Alias = x.Alias,
Description = x.Description
}).ToList();
return response;
}
I now want to unit test this method, but the attribute is fired. I have tried some things to mock the attribute, but without success.
I'm using Moq and Smocks.
This is my unit test without a mocked instance of the attribute:
[TestMethod]
public void GetUserGroups_UserGroupsFound_UserGroupsReturned()
{
Smock.Run(context =>
{
//Arrange
Setup();
m_Container
.RegisterMock<IGroupManager>()
.Setup(x => x.FindAllFromCache())
.Returns(new List<Concept.Security.MasterData.Domain.Group>()
{
new Concept.Security.MasterData.Domain.Group()
{
Name = "MyUserGroup",
Alias = "My User Group",
Description = "My user group description",
System = false,
Authorizations = "000001111100000000"
},
new Concept.Security.MasterData.Domain.Group()
{
Name = "MySecondUserGroup",
Alias = "My Second User Group",
Description = "My second user group description",
System = false,
Authorizations = "000000000000000000"
}
});
var identityService = new UserManagementService(m_Container, m_UserAuthorizationManager.Object, m_IdentityService.Object);
//** begin add mocked attribute **//
//** end add mocked attribute **//
//Act
var response = identityService.GetUserGroups();
//Assert
Assert.AreEqual(2, response.Count);
Assert.AreEqual(1, response.Where(x => x.Alias == "MyUserGroup").Count());
Assert.AreEqual(1, response.Where(x => x.Alias == "MySecondUserGroup").Count());
Assert.AreEqual(2, response.Where(x => x.Authorizations == null).Count());
});
}
Running this results in an exception because the attribute tries to connect the external services and they aren't (and can't be) setup to receive requests.
So, I try to add a mocked attribute:
//** begin add mocked attribute **//
var identityService = new UserManagementService(m_Container, m_UserAuthorizationManager.Object, m_IdentityService.Object);
var IsAuthorizedAttribute = new Mock<IsAuthorizedAttribute>(MockBehavior.Strict, new object[] { SecurityAction.Demand });
IsAuthorizedAttribute.Setup(x => x.CreatePermission()).Returns(new PrincipalPermission(PermissionState.None));
TypeDescriptor.AddAttributes(identityService, IsAuthorizedAttribute.Object);
//** end add mocked attribute **//
But this one is calling the constructor of the attribute where I set up the external source. When I put this constructor in a try/catch and silently disposing the exception, I have an error on IsAuthorizedAttribute.Object object can't be found.
What are other options to not fire the attribute?
Constructors should not access externals; otherwise it will be difficult to bypass for testing, as you know.
A simple way is to make static bool field to bypass. This does not look so good but maybe enough.
public class IsAuthorizedAttribute : CodeAccessSecurityAttribute
{
// set true in the test initialization
private static bool s_byPass;
public IsAuthorizedAttribute(SecurityAction action) : base(action)
{
if (!s_byPass)
{
// setup
}
}
private static bool IsAuthorised(string entityObject, string field, char expected, ServicesConfiguration servicesConfiguration)
{
if (s_byPass) { return true; }
//check external stuff
}
}
Another better approach is to extract the external dependency to another class so that you can mock it. Mocking external dependencies is a typical pattern of a unit test.
public class IsAuthorizedAttribute : CodeAccessSecurityAttribute
{
// set mock here in the test initialization.
// I assume external accessor can be a static field.
private static ExternalAccessor m_accessor = new ExternalAccessor();
private static bool IsAuthorised(string entityObject, string field, char expected, ServicesConfiguration servicesConfiguration)
{
return m_accessor.Check();
}
}
public class ExternalAccessor
{
private bool m_initialized;
private void Setup()
{
// setup
m_initialized = true;
}
public virtual bool Check()
{
// You can call setup anytime but the constructor.
if (!m_initialized) { Setup(); }
// check external stuff
}
}
My unit testing method is as follows
[Test]
public void TrackPublicationChangesOnCDSTest()
{
//Arrange
// objDiskDeliveryBO = new DiskDeliveryBO();
//Act
var actualResult = objDiskDeliveryBO.TrackPublicationChangesOnCDS();
//Assert
var expectedZipName = 0;
Assert.AreEqual(expectedZipName, actualResult);
}
The Actual method TrackPublicationChangesOnCDS in BO is as follows
public int TrackPublicationChangesOnCDS()
{
var resultFlag = -1;
try
{
string pubUpdateFileCDSPath = CommonCalls.PubUpdateFileCDSPath;
string pubUpdateFileLocalPath = CommonCalls.PubUpdateFileLocalPath;
if (File.Exists(pubUpdateFileCDSPath))
File.Copy(pubUpdateFileCDSPath, pubUpdateFileLocalPath, true);
if (File.Exists(pubUpdateFileLocalPath))
{
string[] pubRecords = File.ReadAllLines(pubUpdateFileLocalPath);
var pubRecordsExceptToday = pubRecords.Where(p => !p.Trim().EndsWith(DateTime.Now.ToString("dd/MM/yy"))).ToList();
resultFlag = new DiskDeliveryDAO().TrackPublicationChangesOnCDS(pubRecordsExceptToday);
File.WriteAllText(pubUpdateFileLocalPath, string.Empty);
string[] pubRecordsCDS = File.ReadAllLines(pubUpdateFileCDSPath);
var pubRecordsTodayCDS = pubRecordsCDS.Where(p => p.Trim().EndsWith(DateTime.Now.ToString("dd/MM/yy"))).ToList();
File.WriteAllLines(pubUpdateFileCDSPath, pubRecordsTodayCDS);
}
return resultFlag;
}
catch (Exception)
{
return -1;
}
}
While debugging Debugger comes till
string pubUpdateFileCDSPath = CommonCalls.PubUpdateFileCDSPath;
But CommonCalls.PubUpdateFileCDSPath; return empty string . It should return a file path . when the method is called directly it works fine . It doesn't work when it is called inside a unit testing method.
CommonCalls.PubUpdateFileCDSPath is a static property defined as below .
public static string PubUpdateFileCDSPath
{
get { return GetXmlConfigValue("PubUpdateFileCDSPath"); }
}
public static string GetXmlConfigValue(string nodeName)
{
var xml = new XmlDocument();
xml.Load(ConfigValuesXml);
var node = xml.SelectSingleNode("JanesOfflineDeliveryService/" + nodeName);
return node != null ? node.InnerText : string.Empty;
}
Configvaluesxml is a xml file path . Contents of the file is
<JanesOfflineDeliveryService>
<PubUpdateFileCDSPath>D:\OfflineDelivery\CDS\pub_update.txt</PubUpdateFileCDSPath>
<PubUpdateFileLocalPath>D:\pub_update.txt</PubUpdateFileLocalPath>
</JanesOfflineDeliveryService>
In your test scenario GetXmlConfigValue("PubUpdateFileCDSPath") does not exist, so string empty is returned. Thats why you should avoid static methods, because they are not mockable. A workaround could be to pass the path variables into the method.
Using static dependencies make unit testing code in isolation difficult. invert the dependency by abstracting and injecting them into the dependent class.
public interface ICommonCalls {
string PubUpdateFileCDSPath { get; }
string PubUpdateFileLocalPath { get; }
}
the implementation of the above interface would either wrap the your static calls or better yet just implement them.
The dependent class would be refactored to allow for the dependency inversion.
public class DiskDeliveryBO {
private readonly ICommonCalls CommonCalls;
public DiskDeliveryBO(ICommonCalls common) {
this.CommonCalls = common;
}
//...other code removed for brevity.
}
However the target method also has a lot of tight coupling to implementation concerns like the file system. That too should be abstracted and inverted out of the dependent class.
I have the followed function and trying to add Unit Test on a old project. I'm a beginner in Unit Test so forgive me if the question is stupid ...
public static string GetDefaultName(bool isResponsive)
{
//Read web.config file
Configuration configuration = WebConfigurationManager.OpenWebConfiguration(System.Web.HttpContext.Current.Request.ApplicationPath);
if (!isResponsive)
{
if (configuration.AppSettings.Settings.AllKeys.Contains("defaultTheme"))
{
return configuration.AppSettings.Settings["defaultTheme"].Value;
}
else
return "default";
}
else
{
// ...
}
}
And I'm trying to write an Unit Test in this way :
[TestMethod]
public void ReturnDefaulThemeNametIfThemeIsResponsive()
{
var theme = new Theme {isResponsive = true};
var defaultName = Themes.GetDefaultName(theme.isResponsive);
Assert.AreEqual(defaultName, "defaultThemeResponsive");
}
I wonder what is the best way to test this static function, and how to mock the part who read the web.config file ?
I try to stay away from static utilities that have dependencies as they are difficult to unit test. But in this case it is possible. You will have to do some refactoring.
First you need to abstract all calls to access configuration.
public interface IThemeSettings {
bool Contains(string key);
string this[string key] { get; }
}
You can then update the static Themes utility class to use this abstraction as a dependency
public static class Themes {
private static IThemeSettings themes;
public static void Configure(Func<IThemeSettings> factory) {
if (factory == null) throw new InvalidOperationException("Must provide a valid factory method");
themes = factory();
}
public static string GetDefaultName(bool isResponsive) {
if (themes == null) throw new InvalidOperationException("Themes has not been configured.");
string result = string.Empty;
if (!isResponsive) {
if (themes.Contains("defaultTheme")) {
result = themes["defaultTheme"];
} else
result = "default";
} else {
// ...
}
return result;
}
//...
}
That wat you can now configure the utility to use mocks when testing
[TestMethod]
public void ReturnDefaulThemeNametIfThemeIsResponsive() {
//Arrange
var key = "defaultTheme";
var expected = "defaultThemeResponsive";
var mockSettings = new Mock<IThemeSettings>();
mockSettings.Setup(m => m.Contains(key)).Returns(true);
mockSettings.Setup(m => m[key]).Returns(expected);
//In production you would also do something like this with
//the actual production implementation, not a mock
Themes.Configure(() => mockSettings.Object);
var theme = new Theme { isResponsive = true };
//Act
var defaultName = Themes.GetDefaultName(theme.isResponsive);
//Assert
Assert.AreEqual(expected, defaultName);
}
In this case I used Moq as the mocking framework.
Some advice. Try not to have your classes tightly coupled to HttpContext. Your classes should depend on abstractions and not on concretions.
The way your method is designed at the moment does not allow you to mock the part that reads the config file. If you want to be able to do that you need to make it a parameter to your method. One way to make that easier is to define an interface like
public interface ISetting
{
string GetConfigItem(string itemName);
}
Then wrap the Configuration object in a settings manager class that implements this.
public class MySettings:ISetting
{
public string GetConfigItem(string ItemName)
{
// return value of the setting. In your case code that gets value of "defaultTheme"
}
}
Your method will now have a dependency on ISetting.
For testing purposes you can create a mock that implements the interface and will return what ever value you want independent of the current state and content of the web.config
public class SettingsTestHelper:ISetting
{
private _valueToReturn;
public SettingsTestHelper(string valueToReturn)
{
_valueToReturn=valueToReturn;
}
public string GetConfigItem(string itemName)
{
return valueToReturn;
}
}
With this you can now create a unit test(doesn't compile, but you'll get the idea)
[TestMethod]
public void CanGetSetting()
{
var helper = new SettingsTestHelper("default");
var result = ClasThatImplementsYourStaticMethod.GetDefaultName(helper, true);
Assert.AreEqual(expected, actual);
}
I have a custom DisconnectedDbContext for use with self state tracking POCOs in a web app.
public abstract class DisconnectedDbContext : DbContext
{
protected DisconnectedDbContext()
{
var objAdapterContext = ((IObjectContextAdapter)this).ObjectContext;
}
}
I subclass this for some unit testing:
public class FruityContext : DisconnectedDbContext
{
public virtual DbSet<FruitBowl> FruitBowls { get; set; }
public virtual DbSet<Fruit> Fruits { get; set; }
}
And using Moq in a TestMethod as below:
[TestMethod]
public void CreateAFruityContext()
{
var dbc = new FruityContext();
Assert.IsNotNull(dbc);
var mockSet = new Mock<DbSet<FruitBowl>>();
var mockContext = new Mock<FruityContext>();
mockContext.Setup(m => m.FruitBowls).Returns(mockSet.Object);
var mo = mockContext.Object;
Assert.IsNotNull(mo);
}
Now this is not an actual TestMethod so I don't want to get sidetracked about that.
My problem is that for the creation of var dbc in this method, objAdapterContext in the constructor call is not null however for var mo it is null. I need objAdapterContext to be not null, as per non-mocked objects because I tap into this to handle the ObjectMaterialized event of the ObjectContext.
So the Moq wrapper is changing the behaviour of my code. Is there something I can do about this?
Use this:
mockSet.CallBase = true;
mockContext.CallBase = true;
I encountered a class during my work that looks like this:
public class MyObject
{
public int? A {get; set;}
public int? B {get; set;}
public int? C {get; set;}
public virtual int? GetSomeValue()
{
//simplified behavior:
return A ?? B ?? C;
}
}
The issue is that I have some code that accesses A, B and C and calls the GetSomeValue() method (now, I'd say this is not a good design, but sometimes my hands are tied ;-)). I want to create a mock of this object, which, at the same time, has A, B and C set to some values. So, when I use moq as such:
var m = new Mock<MyObject>() { DefaultValue = DefaultValue.Mock };
lets me setup a result on GetSomeValue() method, but all the properties are set to null (and setting up all of them using Setup() is quite cumbersome, since the real object is a nasty data object and has more properties than in above simplified example).
So on the other hand, using AutoFixture like this:
var fixture = new Fixture();
var anyMyObject = fixture.CreateAnonymous<MyObject>();
Leaves me without the ability to stup a call to GetSomeValue() method.
Is there any way to combine the two, to have anonymous values and the ability to setup call results?
Edit
Based on nemesv's answer, I derived the following utility method (hope I got it right):
public static Mock<T> AnonymousMock<T>() where T : class
{
var mock = new Mock<T>();
fixture.Customize<T>(c => c.FromFactory(() => mock.Object));
fixture.CreateAnonymous<T>();
fixture.Customizations.RemoveAt(0);
return mock;
}
This is actually possible to do with AutoFixture, but it does require a bit of tweaking. The extensibility points are all there, but I admit that in this case, the solution isn't particularly discoverable.
It becomes even harder if you want it to work with nested/complex types.
Given the MyObject class above, as well as this MyParent class:
public class MyParent
{
public MyObject Object { get; set; }
public string Text { get; set; }
}
these unit tests all pass:
public class Scenario
{
[Fact]
public void CreateMyObject()
{
var fixture = new Fixture().Customize(new MockHybridCustomization());
var actual = fixture.CreateAnonymous<MyObject>();
Assert.NotNull(actual.A);
Assert.NotNull(actual.B);
Assert.NotNull(actual.C);
}
[Fact]
public void MyObjectIsMock()
{
var fixture = new Fixture().Customize(new MockHybridCustomization());
var actual = fixture.CreateAnonymous<MyObject>();
Assert.NotNull(Mock.Get(actual));
}
[Fact]
public void CreateMyParent()
{
var fixture = new Fixture().Customize(new MockHybridCustomization());
var actual = fixture.CreateAnonymous<MyParent>();
Assert.NotNull(actual.Object);
Assert.NotNull(actual.Text);
Assert.NotNull(Mock.Get(actual.Object));
}
[Fact]
public void MyParentIsMock()
{
var fixture = new Fixture().Customize(new MockHybridCustomization());
var actual = fixture.CreateAnonymous<MyParent>();
Assert.NotNull(Mock.Get(actual));
}
}
What's in MockHybridCustomization? This:
public class MockHybridCustomization : ICustomization
{
public void Customize(IFixture fixture)
{
fixture.Customizations.Add(
new MockPostprocessor(
new MethodInvoker(
new MockConstructorQuery())));
fixture.Customizations.Add(
new Postprocessor(
new MockRelay(t =>
t == typeof(MyObject) || t == typeof(MyParent)),
new AutoExceptMoqPropertiesCommand().Execute,
new AnyTypeSpecification()));
}
}
The MockPostprocessor, MockConstructorQuery and MockRelay classes are defined in the AutoMoq extension to AutoFixture, so you'll need to add a reference to this library. However, note that it's not required to add the AutoMoqCustomization.
The AutoExceptMoqPropertiesCommand class is also custom-built for the occasion:
public class AutoExceptMoqPropertiesCommand : AutoPropertiesCommand<object>
{
public AutoExceptMoqPropertiesCommand()
: base(new NoInterceptorsSpecification())
{
}
protected override Type GetSpecimenType(object specimen)
{
return specimen.GetType();
}
private class NoInterceptorsSpecification : IRequestSpecification
{
public bool IsSatisfiedBy(object request)
{
var fi = request as FieldInfo;
if (fi != null)
{
if (fi.Name == "__interceptors")
return false;
}
return true;
}
}
}
This solution provides a general solution to the question. However, it hasn't been extensively tested, so I'd love to get feedback on it.
Probably there is a better why, but this works:
var fixture = new Fixture();
var moq = new Mock<MyObject>() { DefaultValue = DefaultValue.Mock };
moq.Setup(m => m.GetSomeValue()).Returns(3);
fixture.Customize<MyObject>(c => c.FromFactory(() => moq.Object));
var anyMyObject = fixture.CreateAnonymous<MyObject>();
Assert.AreEqual(3, anyMyObject.GetSomeValue());
Assert.IsNotNull(anyMyObject.A);
//...
Initially I tried to use fixture.Register(() => moq.Object); instead of fixture.Customize but it registers the creator function with OmitAutoProperties() so it wouldn't work for you case.
As of 3.20.0, you can use AutoConfiguredMoqCustomization. This will automatically configure all mocks so that their members' return values are generated by AutoFixture.
var fixture = new Fixture().Customize(new AutoConfiguredMoqCustomization());
var mock = fixture.Create<Mock<MyObject>>();
Assert.NotNull(mock.Object.A);
Assert.NotNull(mock.Object.B);
Assert.NotNull(mock.Object.C);