I have a test method with the following signature:
public void TheBigTest(MyClass data, decimal result)
{
And I'd like to run this in XUnit 2.1. I've got my CalculationData class all set up and that works if I remove the second parameter. But when I try to pass in the expected result as a second parameter by doing:
[Theory, ClassData(typeof(CalculationData)), InlineData(8893)]
It doesn't work. The test fails with a:
The test method expected 2 parameter values, but 1 parameter value was
provided.
Any ideas?
The class specified in the ClassData attribute needs to be an enumerable class that returns all of the parameters for the test method, not just the first one.
So, in your example, you would need something like:
public class CalculationData : IEnumerable<object[]>
{
IEnumerable<object[]> parameters = new List<object[]>()
{
new object[] { new MyClass(), 8893.0m },
new object[] { new MyClass(), 1234.0m },
// ... other data...
};
public IEnumerator<object[]> GetEnumerator()
{
return parameters.GetEnumerator();
}
IEnumerator IEnumerable.GetEnumerator()
{
return GetEnumerator();
}
}
You can then add parameters to your MyClass class to enhance your test data.
Related
I am trying to get to grips with TDD, I have reviewed some tutorials and am trying to implement tests on my validation classes that I have created using fluent validation.
public SomeFormValidator()
{
RuleFor(x => x.MyClass).NotNull()
.WithMessage("MyClass cannot be null");
}
I have looked at the TDD examples specifically for fluent validation and created a couple of tests
[Test]
public void Should_have_error_when_MyClass_is_null()
{
MyClass myClass = null;
SomeFormValidator.ShouldHaveValidationErrorFor(aup => aup.MyClass, myClass);
}
[Test]
public void Should_not_have_error_when_MyClass_is_not_null()
{
MyClass myClass = new MyClass();
SomeFormValidator.ShouldNotHaveValidationErrorFor(aup => aup.MyClass, myClass);
}
I would like to now test that the string "MyClass cannot be null" is returned when it is null. I have not been able to find anything covering returned message and I have not been able to work it out.
Thanks to the guidance of #Surgey I was able to come up with a solution that uses the fluent validation built in methods, in addition to that I have been able to better layout my test which I have added below
using FluentValidation.TestHelper;
using NUnit.Framework;
using MyProject.Models...
using MyProject...
namespace MyProject.Tests.Classes.Validation
{
[TestFixture]
public class SomeFormValidatorTest
{
private SomeFormValidator SomeFormValidator;
[SetUp]
public void Setup()
{
SomeFormValidator = new SomeFormValidator();
}
[Test]
public void Should_display_correct_error_message_MyClass_is_null()
{
//arrange
MyClass myClass = null;
//act
var result = SomeFormValidator.ShouldHaveValidationErrorFor(x => x.MyClass, myClass);
//assert
result.WithErrorMessage("MyClass is required");
//first attempt prior to finding WithErrorMessage exists
//foreach (var r in result)
//{
// Assert.AreEqual("MyClass is required", r.ErrorMessage);
//}
}
}
}
I am using result.WithErrorMessage as that is was is provided in the result but I have left the foreach in, but commented, as I find the error message produced by using Assert.AreEqual produce a better message in the test runner.
There is Arrange-Act-Assert (AAA) technique that helps to structure unit tests properly.
Arrange
First of all, you need to create a System Under Test (SUT) and inputs. In this case that are SomeFormValidator and SomeForm instances:
// arrange
var sut = new SomeFormValidator();
var someFormWithNullProp = new SomeForm { MyClass = null };
Act
Then you need to call the SUT to perform real work. For validators, that is the Validate() method call:
// act
ValidationResult result = sut.Validate<SomeForm>(someFormWithNullProp);
Assert
The last part of the unit test checks if the actual result matches the expectations:
// assert
Assert.False(result.IsValid);
Assert.AreEqual(
"MyClass cannot be null",
result.Errors.Single().ErrorMessage);
I need to change a function that accepts one Expression with one property inside and give it the ability to work with 2 properties at least.
I have the following base class that contains nested ElementHelper class
public class DomainObjectViewModel<TModel> where TModel : DomainObject
{
public class ElementHelper
{
public static void Create<T1>(TModel model, Expression<Func<TModel, T1>> expression)
{
var getPropertyInfo = GetPropertyInfo(expression);
//Do cool stuff
}
private static PropertyInfo GetPropertyInfo<T1>(Expression<Func<TModel, T1>> propertyExpression)
{
return (PropertyInfo)((MemberExpression)propertyExpression.Body).Member;
}
}
}
-ElementHelper class contains a Create function that gets the propertyInfo of the expression and only works if you pass one property in the expression.
Then I have the following inherited class that uses the helper function in the constructor.
public class ProductViewModel : DomainObjectViewModel<ProductEditViewModel>
{
public ProductViewModel(ProductEditViewModel model)
{
//It works for one property in the Expression
ElementHelper.Create(model, x => x.LaunchDate);
//Give the ability to pass multiple paramenters in the expression
ElementHelper.Create(model, x => new { x.LaunchDate, x.ApplyLaunchDateChanges });
}
}
I think I can use NewExpression (new { x.LaunchDate, x.ApplyLaunchDateChanges }) in order to pass it a collection of properties, but I cannot make it work.
Would you use same approach?
How you can split the passed Expression so you can get the propertyinfo of each properties found in the NewExpression object?
Well, since ElementHelper.GetPropertyInfo is your own method, you can decide what is allowed to pass, and then handle it appropriately inside that method.
Currently you handle only MemberExpression, so that's why it works only with single property accessor. If you want to be able to pass new { ... }, you need to add support for NewExpression like this:
private static IEnumerable<PropertyInfo> GetPropertyInfo<T1>(Expression<Func<TModel, T1>> propertyExpression)
{
var memberExpression = propertyExpression.Body as MemberExpression;
if (memberExpression != null)
return Enumerable.Repeat((PropertyInfo)memberExpression.Member, 1);
var newExpression = propertyExpression.Body as NewExpression;
if (newExpression != null)
return newExpression.Arguments.Select(item => (PropertyInfo)((MemberExpression)item).Member);
return Enumerable.Empty<PropertyInfo>(); // or throw exception
}
Is it possible for a Controller method to handle all Posted items which derive from a particular base class? The idea is to be able to dispatch Commands by posting them to an endpoint. When I try the following, the "cmd" parameter in the Post method is always null.
Example
//the model:
public abstract class Command{
public int CommandId{get; set;}
}
public class CommandA:Command{
public string StringParam{get; set;}
}
public class CommandB:Command{
public DateTime DateParam{get; set;}
}
//and in the controller:
public HttpResponseMessage Post([FromBody]Command cmd)
{
//cmd parameter is always null when I Post a CommandA or CommandB
//it works if I have separate Post methods for each Command type
if (ModelState.IsValid)
{
if (cmd is CommandA)
{
var cmdA = (CommandA)cmd;
// do whatever
}
if (cmd is CommandB)
{
var cmdB = (CommandB)cmd;
//do whatever
}
//placeholder return stuff
var response = Request.CreateResponse(HttpStatusCode.Created);
var relativePath = "/api/ToDo/" + cmd.TestId.ToString();
response.Headers.Location = new Uri(Request.RequestUri, relativePath);
return response;
}
throw new HttpResponseException(HttpStatusCode.BadRequest);
}
Again, when I try this approach the Post method gets called, but the parameter is always null from the framework. However if I replace it with a Post method with a specific CommandA parameter type, it works.
Is what I'm attempting possible? Or does every message type need a separate handler method in the controller?
If you are sending data in Json format, then following blog gives more details about how hierarchies deserialization can be achieved in json.net:
http://dotnetbyexample.blogspot.com/2012/02/json-deserialization-with-jsonnet-class.html
here's my controller
[POST("signup")]
public virtual ActionResult Signup(UserRegisterViewModel user)
{
if (ModelState.IsValid)
{
var newUser = Mapper.Map<UserRegisterViewModel, User>(user);
var confirmation = _userService.AddUser(newUser);
if (confirmation.WasSuccessful)
return RedirectToAction(MVC.Home.Index());
else
ModelState.AddModelError("Email", confirmation.Message);
}
return View(user);
}
here's my unit test:
[Test]
public void Signup_Action_When_The_User_Model_Is_Valid_Returns_RedirectToRouteResult()
{
// Arrange
const string expectedRouteName = "~/Views/Home/Index.cshtml";
var registeredUser = new UserRegisterViewModel { Email = "newuser#test.com", Password = "123456789".Hash()};
var confirmation = new ActionConfirmation<User>
{
WasSuccessful = true,
Message = "",
Value = new User()
};
_userService.Setup(r => r.AddUser(new User())).Returns(confirmation);
_accountController = new AccountController(_userService.Object);
// Act
var result = _accountController.Signup(registeredUser) as RedirectToRouteResult;
// Assert
Assert.IsNotNull(result, "Should have returned a RedirectToRouteResult");
Assert.AreEqual(expectedRouteName, result.RouteName, "Route name should be {0}", expectedRouteName);
}
Unit test failed right here.
var result = _accountController.Signup(registeredUser) as RedirectToRouteResult;
when I debug my unit test, I got following error message: "Missing type map configuration or unsupported mapping."
I think its because configuration is in web project, not the unit test project. what should I do to fix it?
You need to have the mapper configured, so in your test class set up, not the per-test setup, call the code to set up the mappings. Note, you'll also probably need to modify your expectation for the user service call as the arguments won't match, i.e, they are different objects. Probably you want a test that checks if the properties of the object match those of the model being passed to the method.
You should really use an interface for the mapping engine so that you can mock it rather than using AutoMapper otherwise it is an integration test not a unit test.
AutoMapper has an interface called IMappingEngine that you can inject into your controller using your IoC container like below (this example is using StructureMap).
class MyRegistry : Registry
{
public MyRegistry()
{
For<IMyRepository>().Use<MyRepository>();
For<ILogger>().Use<Logger>();
Mapper.AddProfile(new AutoMapperProfile());
For<IMappingEngine>().Use(() => Mapper.Engine);
}
}
You will then be able to use dependency injection to inject AutoMapper's mapping engine into your controller, allowing you to reference your mappings like below:
[POST("signup")]
public virtual ActionResult Signup(UserRegisterViewModel user)
{
if (ModelState.IsValid)
{
var newUser = this.mappingEngine.Map<UserRegisterViewModel, User>(user);
var confirmation = _userService.AddUser(newUser);
if (confirmation.WasSuccessful)
return RedirectToAction(MVC.Home.Index());
else
ModelState.AddModelError("Email", confirmation.Message);
}
return View(user);
}
You can read more about this here: How to inject AutoMapper IMappingEngine with StructureMap
Probably it is cool to abstract mapping into MappingEngine.
Sometimes I use following approach to IOC Automapper
In IOC builder:
builder.RegisterInstance(AutoMapperConfiguration.GetAutoMapper()).As<IMapper>();
where GetAutoMapper is:
public class AutoMapperConfiguration
{
public static IMapper GetAutoMapper()
{
var config = new MapperConfiguration(cfg =>
{
cfg.AddProfile<OrderModelMapperProfile>();
cfg.AddProfile<OtherModelMapperProfile>();
//etc;
});
var mapper = config.CreateMapper();
return mapper;
}
}
And finally in Controller ctor
public MyController(IMapper mapper)
{
_mapper = mapper;
}
I'm trying and failing to use an ExpressionVisitor to modify an expression that calls a method. I have a SearchService that encapsulates the search logic and want to be able to amend the search arguments passed.
The class in which the SearchFunc should be modified and run:
public class SearchService
{
public Expression<Func<string, string, List<int>>> SearchFunc { get; set; }
public void Run()
{
SearchModifier modifier = new SearchModifier();
Expression<Func<string, string, List<int>>> newFunc = (Expression<Func<string, string, List<int>>>)modifier.Modify(SearchFunc);
}
}
SearchModifier is defined as:
public class SearchModifier : ExpressionVisitor
{
public Expression Modify(Expression expression)
{
return Visit(expression);
}
protected override Expression VisitMethodCall(MethodCallExpression node)
{
Debug.Print(string.Format("VisitMethodCall: {0}", node.ToString()));
//VisitMethodCall: value(ExpressionTree_test.MainWindow)._adminRepository.SearchUsers("orig val", "orig val2")
//trying to use the Update method to create an amended MethodCallExpression
List<ConstantExpression> newargs = new List<ConstantExpression>();
newargs.Add(Expression.Constant("my new arg 1", typeof(string)));
newargs.Add(Expression.Constant("my new arg 2", typeof(string)));
MethodCallExpression methodCallExpression = node.Update(node, newargs);
//causes exception
//Method 'System.Collections.Generic.List`1[System.Int32] SearchUsers(System.String, System.String)' declared
//on type 'ExpressionTree_test.AdminRepository' cannot be called
//with instance of type 'System.Collections.Generic.List`1[System.Int32]'
Debug.Print(string.Format("Amended VisitMethodCall: {0}", methodCallExpression.ToString()));
return base.VisitMethodCall(node);
}
The Run method is called like this:
_searchService = new SearchService();
_searchService.SearchFunc = (t, s) => _adminRepository.SearchUsers("orig val", "orig val2");
I can't find much information on using the MethodCallExpression.Update method so am not sure I'm doing this correctly. How to I change the values of the arguments in the method?
Of course there may be a better way of doing this and any suggestions gratefully received...
You're not using the result of the Update method. You should pass it to base.VisitMethodCall instead of node:
return base.VisitMethodCall(methodCallExpression);
EDIT
Sorry, I misread the question... The first argument to Update is not the expression node being visited, it's the instance on which the method is called. So the code should be:
node.Update(node.Object, newargs);