I have Video Service class as follows:
public class VideoService
{
private IFileReader _fileReader;
private IVideoRepository _repository;
public string _videoPath;
public VideoService(IFileReader fileReader, IVideoRepository repository)
{
_fileReader = fileReader;
_repository = repository;
}
public string ReadVideoTitle()
{
var str = _fileReader.Read(_videoPath);
if (str == "")
{
return "";
}
else
{
return "b";
}
}
}
then there is IFileReader and FileReader as below:
public interface IFileReader
{
string Read(string path);
}
public class FileReader : IFileReader
{
public string Read(string path)
{
return File.ReadAllText(path);
}
}
Now i have my unit test:
[TestFixture]
public class VideoServiceTests
{
private VideoService _videoService;
private Mock<IFileReader> _fileReader;
private Mock<IVideoRepository> _repository;
private string _videoPath;
[SetUp]
public void SetUp()
{
_fileReader = new Mock<IFileReader>();
_repository = new Mock<IVideoRepository>();
_videoPath = #"test.txt";
_videoService = new VideoService(_fileReader.Object, _repository.Object);
}
[Test]
public void ReadVideoTitle_EmptyFile_ReturnError()
{
_fileReader.Setup(fr => fr.Read(_videoPath)).Returns("");
var result = _videoService.ReadVideoTitle();
Assert.That(result, Does.Contain("").IgnoreCase);
}
My problem is and what i am not understanding. When i do _fileReader.Setup ..
My understanding is it is a fake reader and not FileReader class right?, therefore when i say put whatever in Read parameter like: test.txt then i say i am expecting Returns "". In Assert i am comparing it to what i get from ReadVideoTitle. However what is the sense of Assert here? Since _fileReader is just interface and not real class it will not really look and try to read fake test.txt file and look for output. Therefore first question why i always get test Success whatever i put in _fileReader.Setup. How it checks whether is Success? Shouldn'e it be just Vlaidate() if Read was really called, since it's nt really testing values? Can anyone be so kind and explain me how current example test works and what is really testing because so far i am lost.
Related
Why does this unit test not fail when no guard clause is present?
[Test]
public void ConstructorLooksGuardedAgainstNulls()
{
// ARRANGE
var fixture = new Fixture();
var assertion = fixture.Create<GuardClauseAssertion>();
// ACT & ASSERT
assertion.Verify(typeof(TestClass).GetConstructors(BindingFlags.Public));
}
Classes used in unit test:
public class TestBaseClass
{
private readonly string _firstDependency;
private readonly string _secondDependency;
protected TestBaseClass(string firstDependency, string secondDependency)
{
_firstDependency = firstDependency;
_secondDependency = secondDependency;
}
}
public class TestClass : TestBaseClass
{
public TestClass(string firstDependency)
: base(firstDependency, string.Empty)
{
}
}
I removed all the irrelevant lines.
This will return all public constructors, and then the test will fail as expected:
typeof(TestClass).GetConstructors()
The version with the BindingFlags parameter doesn't return the public constructors (although it reads like it really should do). Because no constructor are found, the test passes
typeof(TestClass).GetConstructors(BindingFlags.Public)
I've written unit tests using NSubstitute library and faced with odd Records behavior.
Assuming I have the code:
public record SomeModel
{
//fields
}
public interface ISomeService
{
public string DoSmth(SomeModel model);
}
public class SomeClass
{
private ISomeService _service;
public SomeClass(ISomeService service)
{
_service = service;
}
public string MethodToTest(SomeModel model)
{
return _service.DoSmth(model);
}
}
And I want to cover it with the Unit test:
[Fact]
public void Test()
{
var model = Substitute.For<SomeModel>();
var service = Substitute.For<ISomeService>();
service.DoSmth(model).Returns("1234");
var sut = new SomeClass(service);
var value = sut.MethodToTest(model); //it returns Empty sting here
value.Should().Be("1234");
}
But it Fails, because MethodToTest returns Empty string.
If I change SomeModel from record to class it is working fine.
Could someone point me to what I missed here?
Update: I changed the model initialization in my test method:
[Fact]
public void Test()
{
var model = new SomeModel();
//other code
}
In this case, it is working. But I still don't understand why it isn't working in the initial example?
Update 2. It is even working if I use Substitute.ForPartsOf:
[Fact]
public void Test()
{
var model = Substitute.ForPartsOf<SomeModel>();
//other code
}
I can't get Moq to mock an object that gets created in a static method.
Here is my moq and code
code:
public interface IConfigHelper
{
string GetConfiguration(string sectionName, string elementName);
}
public class ConfigHelper : IConfigHelper
{
public ConfigHelper() { }
public virtual string GetConfiguration(string sectionName, string elementName)
{
string retValue = String.Empty;
//Does things to get configuration and return a value
return retValue;
}
}
public class myRealClass
{
public myRealClass(){}
public string myworkingMethod()
{
var retValue = String.Empty;
retValue = utilSvc.GetConfigurationValue();
return retValue;
}
}
public static class utilSvc
{
public static string GetConfigurationValue()
{
ConfigHelper configUtil = new ConfigHelper(); //NOT BEING MOCKED
return configUtil.GetConfiguration("sectionName/sectionElement", "ClinicalSystem");
}
}
the Test using Moq
[TestFixture(TestName = "Tests")]
public class Tests
{
private Mock<IConfigHelper> configHelperMOCK;
[SetUp]
public void Setup()
{
configHelperMOCK = new Mock<IConfigHelper>();
}
[Test]
public void serviceIsBPManagementForValidSource()
{
//Arrange
string sectionName = "sectionName/sectionElement";
string clinicalElementName = "ClinicalSystem";
string clinicalElementValue = "Zedmed";
configHelperMOCK.Setup(s => s.GetConfiguration(sectionName, clinicalElementName)).Returns(clinicalElementValue);
//act
// the call to myRealClass
//assert
// test assertions
}
}
The issue that I am having is with this line:
ConfigHelper configUtil = new ConfigHelper(); //NOT BEING MOCKED
I cannot get the moq to Mock the object.
I do not want the code to read the config file. I wish to moq away this instance of ConfigHelper
You can't wrap the static class/method but you can redirect it
public static class UtilSvc
{
static UtilSvc()
{
CreatorFunc = () => new ConfigHelper();
}
public static Func<IConfigHelper> CreatorFunc { get; set; }
public static string GetConfigurationValue()
{
var configUtil = CreatorFunc();
return configUtil.GetConfiguration("sectionName/sectionElement",
"ClinicalSystem");
}
}
and then in the test
//...
private Mock<IConfigHelper> configHelperMOCK;
[SetUp]
public void Setup()
{
configHelperMOCK = new Mock<IConfigHelper>();
UtilService.CreatorFunc = () => configHelperMOCK.Object;
}
//...
You cannot mock static class. I would rather propose to inject that IConfigHelper into the myRealClass. That is the usual way how to decouple dependencies and use DI.
public class myRealClass
{
private IConfigHelper _configHelper;
public myRealClass(IConfigHelper configHelper)
{
_configHelper = configHelper;
}
public string myworkingMethod()
{
var retValue = String.Empty;
retValue = _configHelper.GetConfigurationValue();
return retValue;
}
}
Avoid coupling your code to static classes, which in most cases cause you code be to difficult to maintain and test.
Follow the Explicit Dependencies Principle
Methods and classes should explicitly require (typically through
method parameters or constructor parameters) any collaborating objects
they need in order to function correctly.
Give the article a read. It is short and very informative.
If you want to keep the static class then you wrap the static class behind an abstraction.
public interface IUtilSvc {
string GetConfigurationValue();
}
public class utilSvcWrapper : IUtilSvc {
public string GetConfigurationValue() {
return utilSvc.GetConfigurationValue(); //Calling static service
}
}
Or another option is that utlSvc does not have to be static if can be injected into dependent classes
public class utilSvc : IUtilScv {
private readonly IConfigHelper configUtil;
public utilSvc(IConfigHelper configHelper) {
configUtil = configHelper;
}
public string GetConfigurationValue() {
return configUtil.GetConfiguration("sectionName/sectionElement", "ClinicalSystem");
}
}
Inject the IUtilScv into the dependent class so that it is no longer dependent on static class.
public class myRealClass {
private readonly IUtilScv utilSvc;
//Explicit dependency inject via constructor
public myRealClass(IUtilScv utilSvc) {
this.utilSvc = utilSvc;
}
public string myworkingMethod() {
var retValue = utilSvc.GetConfiguration();
return retValue;
}
}
In that case you don't even need IConfigHelper when testing as it has also been abstracted away. And you only need to mock the dependencies needed for the test.
[TestFixture(TestName = "Tests")]
public class Tests {
private Mock<IUtilScv> utilScvMOCK;
[SetUp]
public void Setup() {
utilScvMOCK = new Mock<IUtilScv>();
}
[Test]
public void serviceIsBPManagementForValidSource() {
//Arrange
var expectedClinicalElementValue = "Zedmed";
utilScvMOCK
.Setup(s => s.GetConfiguration())
.Returns(expectedClinicalElementValue)
.Verifiable();
var sut = new myRealClass(utilScvMOCK.Object);
//Act
var actualClinicalElementValue = sut.myworkingMethod();
//Assert
configHelperMOCK.Verify();
Assert.AreEqual(expectedClinicalElementValue, actualClinicalElementValue);
}
}
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 was just working on some application architecture and this may sound like a stupid question but please explain to me how the following works:
Interface:
public interface IMatterDAL
{
IEnumerable<Matter> GetMattersByCode(string input);
IEnumerable<Matter> GetMattersBySearch(string input);
}
Class:
public class MatterDAL : IMatterDAL
{
private readonly Database _db;
public MatterDAL(Database db)
{
_db = db;
LoadAll(); //Private Method
}
public virtual IEnumerable<Matter> GetMattersBySearch(string input)
{
//CODE
return result;
}
public virtual IEnumerable<Matter> GetMattersByCode(string input)
{
//CODE
return results;
}
Controller:
public class MatterController : ApiController
{
private readonly IMatterDAL _publishedData;
public MatterController(IMatterDAL publishedData)
{
_publishedData = publishedData;
}
[ValidateInput(false)]
public JsonResult SearchByCode(string id)
{
var searchText = id; //better name for this
var results = _publishedData.GetMattersBySearch(searchText).Select(
matter =>
new
{
MatterCode = matter.Code,
MatterName = matter.Name,
matter.ClientCode,
matter.ClientName
});
return Json(results);
}
This works, when I call my controller method from jquery and step into it, the call to the _publishedData method, goes into the class MatterDAL.
I want to know how does my controller know to go to the MatterDAL implementation of the Interface IMatterDAL. What if I have another class called MatterDAL2 which is based on the interface. How will my controller know then to call the right method?
I am sorry if this is a stupid question, this is baffling me.
EDIT:
Based on the responses, it seems like this is where the dependency is being resolved:
This is a ninject call:
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<ICpdMatterDAL>().To<CachedCpdData>();
}
Where CachedCpdData is:
public class CachedCpdData : ICpdMatterDAL
{
private static readonly object CacheLockObject = new object();
private readonly MatterDAL _matterData;
public CachedCpdData()
{
_matterData = DomainModel.DataAccessManager.Instance.Matters;
}
public IEnumerable<Matter> GetMattersForAutoCompleteByCode(string input)
{
var cacheKey = string.Format("matter-search-{0}", input ?? "");
var result = HttpRuntime.Cache[cacheKey] as IEnumerable<Matter>;
if (result == null)
{
lock (CacheLockObject)
{
result = HttpRuntime.Cache[cacheKey] as IEnumerable<Matter>;
if (result == null)
{
result = _matterData.GetMattersForAutoCompleteByCode(input).ToList();
HttpRuntime.Cache.Insert(cacheKey, result, null, DateTime.Now.AddSeconds(60), TimeSpan.Zero);
}
}
}
return result;
}
public IEnumerable<Matter> GetMattersByMatterCodeSearch(string input)
{
return _matterData.GetMattersByMatterCodeSearch(input);
}
}
The rason why your code is using the right implementation of IMatterDAL is because it's being passed as a parameter in the constructor of MatterController. I'm almost sure that your code is using some Dependency Injection framework to resolve IMatterDAL.
In fact Ninject is a DI Framework. Your code should have something like
kernel.Bind<IMatterDAL>().To<MatterDAL >();