StructureMap AlwaysUnique does not seem to work with constructor injection - structuremap

I have this configuration in my GeneralRegistry:
ForRequestedType<IClientBonusHistoryLoadTask>().AlwaysUnique().TheDefaultIsConcreteType<ClientBonusHistoryLoadTask>();
And I have this code:
public ClientAdvantagesUpdateTask(IBaseRepo<Client> repository, INHUnitOfWorkProvider uowProvider, IClientBonusHistoryLoadTask clientBonusHistoryLoadTask, ClientBonusHistoryLoadTask masterClientBonusHistoryLoadTask) : base(repository, uowProvider)
{
_clientBonusHistoryLoadTask = clientBonusHistoryLoadTask;
_masterClientBonusHistoryLoadTask =
masterClientBonusHistoryLoadTask;
bool y = clientBonusHistoryLoadTask.Equals
(masterClientBonusHistoryLoadTask);
var task = ObjectFactory.GetInstance<IClientBonusHistoryLoadTask>
();
var task2 =
ObjectFactory.GetInstance<IClientBonusHistoryLoadTask>();
bool x = task.Equals(task2);
}
For some reason, y is true (which is the problem) and x is false
(which works as expected). Is this a bug, or am I doing something
wrong?

Hi I have the same problem, always unique is not making it always unique.
but there is little documentation to know what it is supposed to do.
I use the following:
For<ILeadRepository>().Use<LeadRepository>();
and then inside an object factory method:
LeadRepository instance = ioc.GetInstance<LeadRepository>();
ioc.Inject(typeof(ILeadRepository), instance);
ioc.Inject(typeof(LeadRepository), instance);
where ioc is an IContainer.
Again, I am not sure Inject is supposed to be used like that, but this always pulls the same
instance of LeadRepository out the ioc container after the inject code was run.
Hope this helps or somebody could post on how it is supposed to be done.
I dont like using static factories or static methods, so i made my own factory and everything inside this factory pulls out unique instances out the ioc container, using the code above.
Assuming you want a unique instance, that is a singleton per factory.
and you always want the same instance returned. I found a better way to do this and that is to use subcontainers in the factory:
e.g.
myParentContainer = new Container(x => {
x.AddRegistry<ObjectFactoryModelRegistry>();
x.AddRegistry<ServiceRegistry>();
});
myIoc = myParentContainer.GetNestedContainer();
myIoc.AssertConfigurationIsValid();
then can get same instance by using code below:
myIoc.GetInstance<T>;

Related

Creating objects with dependencies - dependency injection

Let's say we have class:
public class WithDependencies
{
public WithDependencies(IAmDependencyOne first, IAmDependencyTwo second)
// ...
}
Now the question. How do you create objects of WithDependencies class in an application?
I know there are many ways.
new WithDependencies(new DependencyOne(), new DependencyTwo());
new WithDependencies(IoC.Resolve(IDependencyOne), IoC.Resolve(IDependencyTwo());
// register IDependencyOne, IDependencyTwo implementations at app start
IoC.Resolve(WithDependencies);
// register IDependencyOne, IDependencyTwo implementations at app start
// isolate ourselves from concrete IoC Container
MyCustomWithDependenciesFactory.Create();
and so on...
What do you think is the way to do it?
Edit:
Because I don't get answers or I don't understand them I'll try to ask again. Let's say that on some event (button, timer, whatever) I need new object WithDependencies(). How do I create it? Assume IoC container is already configured.
It depends on the context, so it's impossible to provide a single answer. Conceptually you'd be doing something like this from the Composition Root:
var wd = new WithDependencies(new DependencyOne(), new DependencyTwo());
However, even in the absence of a DI Container, the above code isn't always unambiguously the correct answer. In some cases, you might want to share the same dependency among several consumers, like this:
var dep1 = new DependencyOne();
var wd = new WithDependencies(dep1, new DependencyTwo());
var another = AnotherWithDependencies(dep1, new DependencyThree());
In other cases, you might not want to share dependencies, in which case the first option is more correct.
This is just a small glimpse of an entire dimension of DI concerned with Lifetime Management. Many DI Containers can take care of that for you, which is one excellent argument to prefer a DI Container over Poor Man's DI.
Once you start using a DI Container, you should follow the Register Resolve Release pattern when resolving types, letting Auto-wiring take care of the actual composition:
var wd = container.Resolve<WithDependencies>();
The above example assumes that the container is already correctly configured.
If you need to create a dependency which has its own dependencies, you can either A) do it yourself, or B) ask something else to do it for you. Option A negates the benefits of dependency injection (decoupling, etc.), so I would say option B is a better starting point. Now, we have chosen to use the factory pattern, no matter whether it takes the form of a service locator (i.e. IoC.Resolve), a static factory, or an instance factory. The point is that we have delegated that responsibility to an external authority.
There are a number of trade-offs required for static accessors. (I went over them in another answer, so I won't repeat them here.) In order to avoid introducing a dependency on the infrastructure or the container, a solid option is to accept a factory for creating WithDependencies when we need an instance somewhere else:
public class NeedsWithDependencies
{
private readonly IWithDependenciesFactory _withDependenciesFactory;
public NeedsWithDependencies(IWithDependenciesFactory withDependenciesFactory)
{
_withDependenciesFactory = withDependenciesFactory;
}
public void Foo()
{
var withDependencies = _withDependenciesFactory.Create();
...Use the instance...
}
}
Next, we can create a container-specific implementation of the factory:
public class WithDependenciesFactory : IWithDependenciesFactory
{
private readonly IContainer _container;
public WithDependenciesFactory(IContainer container)
{
_container = container
}
public WithDependencies Create()
{
return _container.Resolve<WithDependencies>();
}
}
Now NeedsWithDependencies is completely isolated from any knowledge of how WithDependencies gets created; it also exposes all its dependencies in its constructor, instead of hiding dependencies on static accessors, making it easy to reuse and test.
Defining all those factories can get a little cumbersome, though. I like Autofac's factory relationship type, which will detect parameters of the form Func<TDependency> and automatically inject a function which serves the same purpose as the hand-coded factory above:
public class NeedsWithDependencies
{
private readonly Func<WithDependencies> _withDependenciesFactory;
public NeedsWithDependencies(Func<WithDependencies> withDependenciesFactory)
{
_withDependenciesFactory = withDependenciesFactory;
}
public void Foo()
{
var withDependencies = _withDependenciesFactory();
...Use the instance...
}
}
It also works great with runtime parameters:
public class NeedsWithDependencies
{
private readonly Func<int, WithDependencies> _withDependenciesFactory;
public NeedsWithDependencies(Func<int, WithDependencies> withDependenciesFactory)
{
_withDependenciesFactory = withDependenciesFactory;
}
public void Foo(int x)
{
var withDependencies = _withDependenciesFactory(x);
...Use the instance...
}
}
Sometimes I try to get rid of factories or at least not depend directly on them, so Dependency Injection (without factories) is useful of course.
Therefore I use Google Juice, cause its a small little framework using Java Annotations and you can quickly change your injections / dependencies. Just take a look at it:
http://code.google.com/p/google-guice/

Unexpected Validate behavior with Moq

Moq has been driving me a bit crazy on my latest project. I recently upgraded to version 4.0.10827, and I'm noticing what seems to me to be a new behavior.
Basically, when I call my mocked function (MakeCall, in this example) in the code I am testing, I am passing in an object (TestClass). The code I am testing makes changes to the TestClass object before and after the call to MakeCall. Once the code has completed, I then call Moq's Verify function. My expectation is that Moq will have recorded the complete object that I passed into MakeCall, perhaps via a mechanism like deep cloning. This way, I will be able to verify that MakeCall was called with the exact object I am expecting it to be called with. Unfortunately, this is not what I'm seeing.
I attempt to illustrate this in the code below (hopefully, clarifying it a bit in the process).
I first create a new TestClass object. Its Var property is set to "one".
I then create the mocked object, mockedObject, which is my test subject.
I then call the MakeCall method of mockedObject (by the way, the Machine.Specifications framework used in the example allows the code in the When_Testing class to be read from top to bottom).
I then test the mocked object to ensure that it was indeed called with a TestClass with a Var value of "one". This succeeds, as I expected it to.
I then make a change to the original TestClass object by re-assigning the Var property to "two".
I then proceed to attempt to verify if Moq still thinks that MakeCall was called with a TestClass with a value of "one". This fails, although I am expecting it to be true.
Finally, I test to see if Moq thinks MakeCall was in fact called by a TestClass object with a value of "two". This succeeds, although I would initially have expected it to fail.
It seems pretty clear to me that Moq is only holding onto a reference to the original TestClass object, allowing me to change its value with impunity, adversely affecting the results of my testing.
A few notes on the test code. IMyMockedInterface is the interface I am mocking. TestClass is the class I am passing into the MakeCall method and therefore using to demonstrate the issue I am having. Finally, When_Testing is the actual test class that contains the test code. It is using the Machine.Specifications framework, which is why there are a few odd items ('Because of', 'It should...'). These are simply delegates that are called by the framework to execute the tests. They should be easily removed and the contained code placed into a standard function if that is desired. I left it in this format because it allows all Validate calls to complete (as compared to the 'Arrange, Act Assert' paradigm). Just to clarify, the below code is not the actual code I am having problems with. It is simply intended to illustrate the problem, as I have seen this same behavior in multiple places.
using Machine.Specifications;
// Moq has a conflict with MSpec as they both have an 'It' object.
using moq = Moq;
public interface IMyMockedInterface
{
int MakeCall(TestClass obj);
}
public class TestClass
{
public string Var { get; set; }
// Must override Equals so Moq treats two objects with the
// same value as equal (instead of comparing references).
public override bool Equals(object obj)
{
if ((obj != null) && (obj.GetType() != this.GetType()))
return false;
TestClass t = obj as TestClass;
if (t.Var != this.Var)
return false;
return true;
}
public override int GetHashCode()
{
int hash = 41;
int factor = 23;
hash = (hash ^ factor) * Var.GetHashCode();
return hash;
}
public override string ToString()
{
return MvcTemplateApp.Utilities.ClassEnhancementUtilities.ObjectToString(this);
}
}
[Subject(typeof(object))]
public class When_Testing
{
// TestClass is set up to contain a value of 'one'
protected static TestClass t = new TestClass() { Var = "one" };
protected static moq.Mock<IMyMockedInterface> mockedObject = new moq.Mock<IMyMockedInterface>();
Because of = () =>
{
mockedObject.Object.MakeCall(t);
};
// Test One
// Expected: Moq should verify that MakeCall was called with a TestClass with a value of 'one'.
// Actual: Moq does verify that MakeCall was called with a TestClass with a value of 'one'.
// Result: This is correct.
It should_verify_that_make_call_was_called_with_a_value_of_one = () =>
mockedObject.Verify(o => o.MakeCall(new TestClass() { Var = "one" }), moq.Times.Once());
// Update the original object to contain a new value.
It should_update_the_test_class_value_to_two = () =>
t.Var = "two";
// Test Two
// Expected: Moq should verify that MakeCall was called with a TestClass with a value of 'one'.
// Actual: The Verify call fails, claiming that MakeCall was never called with a TestClass instance with a value of 'one'.
// Result: This is incorrect.
It should_verify_that_make_call_was_called_with_a_class_containing_a_value_of_one = () =>
mockedObject.Verify(o => o.MakeCall(new TestClass() { Var = "one" }), moq.Times.Once());
// Test Three
// Expected: Moq should fail to verify that MakeCall was called with a TestClass with a value of 'two'.
// Actual: Moq actually does verify that MakeCall was called with a TestClass with a value of 'two'.
// Result: This is incorrect.
It should_fail_to_verify_that_make_call_was_called_with_a_class_containing_a_value_of_two = () =>
mockedObject.Verify(o => o.MakeCall(new TestClass() { Var = "two" }), moq.Times.Once());
}
I have a few questions regarding this:
Is this expected behavior?
Is this new behavior?
Is there a workaround that I am unaware of?
Am I using Verify incorrectly?
Is there a better way of using Moq to avoid this situation?
I thank you humbly for any assistance you can provide.
Edit:
Here is one of the actual tests and SUT code that I experienced this problem with. Hopefully it will act as clarification.
// This is the MVC Controller Action that I am testing. Note that it
// makes changes to the 'searchProjects' object before and after
// calling 'repository.SearchProjects'.
[HttpGet]
public ActionResult List(int? page, [Bind(Include = "Page, SearchType, SearchText, BeginDate, EndDate")]
SearchProjects searchProjects)
{
int itemCount;
searchProjects.ItemsPerPage = profile.ItemsPerPage;
searchProjects.Projects = repository.SearchProjects(searchProjects,
profile.UserKey, out itemCount);
searchProjects.TotalItems = itemCount;
return View(searchProjects);
}
// This is my test class for the controller's List action. The controller
// is instantiated in an Establish delegate in the 'with_project_controller'
// class, along with the SearchProjectsRequest, SearchProjectsRepositoryGet,
// and SearchProjectsResultGet objects which are defined below.
[Subject(typeof(ProjectController))]
public class When_the_project_list_method_is_called_via_a_get_request
: with_project_controller
{
protected static int itemCount;
protected static ViewResult result;
Because of = () =>
result = controller.List(s.Page, s.SearchProjectsRequest) as ViewResult;
// This test fails, as it is expecting the 'SearchProjects' object
// to contain:
// Page, SearchType, SearchText, BeginDate, EndDate and ItemsPerPage
It should_call_the_search_projects_repository_method = () =>
s.Repository.Verify(r => r.SearchProjects(s.SearchProjectsRepositoryGet,
s.UserKey, out itemCount), moq.Times.Once());
// This test succeeds, as it is expecting the 'SearchProjects' object
// to contain:
// Page, SearchType, SearchText, BeginDate, EndDate, ItemsPerPage,
// Projects and TotalItems
It should_call_the_search_projects_repository_method = () =>
s.Repository.Verify(r => r.SearchProjects(s.SearchProjectsResultGet,
s.UserKey, out itemCount), moq.Times.Once());
It should_return_the_correct_view_name = () =>
result.ViewName.ShouldBeEmpty();
It should_return_the_correct_view_model = () =>
result.Model.ShouldEqual(s.SearchProjectsResultGet);
}
/////////////////////////////////////////////////////
// Here are the values of the three test objects
/////////////////////////////////////////////////////
// This is the object that is returned by the client.
SearchProjects SearchProjectsRequest = new SearchProjects()
{
SearchType = SearchTypes.ProjectName,
SearchText = GetProjectRequest().Name,
Page = Page
};
// This is the object I am expecting the repository method to be called with.
SearchProjects SearchProjectsRepositoryGet = new SearchProjects()
{
SearchType = SearchTypes.ProjectName,
SearchText = GetProjectRequest().Name,
Page = Page,
ItemsPerPage = ItemsPerPage
};
// This is the complete object I expect to be returned to the view.
SearchProjects SearchProjectsResultGet = new SearchProjects()
{
SearchType = SearchTypes.ProjectName,
SearchText = GetProjectRequest().Name,
Page = Page,
ItemsPerPage = ItemsPerPage,
Projects = new List<Project>() { GetProjectRequest() },
TotalItems = TotalItems
};
Ultimately, your question is whether a mocking framework should take snapshots of the parameters you use when interacting with the mocks so that it can accurately record the state the system was in at the point of interaction rather than the state the parameters might be in at the point of verification.
I would say this is a reasonable expectation from a logical point of view. You are performing action X with value Y. If you ask the mock "Did I perform action X with value Y", you expect it to say "Yes" regardless of the current state of the system.
To summarize the problem you are running into:
You first invoke a method on a mock object with a reference type parameter.
Moq saves information about the invocation along with the reference type parameter passed in.
You then ask Moq if the method was called one time with an object equal to the reference you passed in.
Moq checks its history for a call to that method with a parameter that matches the supplied parameter and answers yes.
You then modify the object that you passed as the parameter to the method call on the mock.
The memory space of the reference Moq is holding in its history changes to the new value.
You then ask Moq if the method was called one time with an object that isn't equal to the reference its holding.
Mock checks its history for a call to that method with a parameter that matches the supplied parameter and reports no.
To attempt to answer your specific questions:
Is this expected behavior?
I would say no.
Is this new behavior?
I don't know, but it's doubtful the project would have at one time had behavior that facilitated this and was later modified to only allow the simple scenario of only verifying a single usage per mock.
Is there a workaround that I am unaware of?
I'll answer this two ways.
From a technical standpoint, a workaround would be to use a Test Spy rather than a Mock. By using a Test Spy, you can record the values passed and use your own strategy for remembering the state, such as doing a deep clone, serializing the object, or just storing the specific values you care about to be compared against later.
From a testing standpoint, I would recommend that you follow the principle "Use The Front Door First". I believe there is a time for state-based testing as well as interaction-based testing, but you should try to avoid coupling yourself to the implementation details unless the interaction is an important part of the scenario. In some cases, the scenario you are interested in will be primarily about interaction ("Transfer funds between accounts"), but in other cases all you really care about is getting the correct result ("Withdraw $10"). In the case of the specification for your controller, this seems to fall into the query category, not the command category. You don't really care how it gets the results you want as long as they are correct. Therefore, I would recommend using state-based testing in this case. If another specification concerns issuing a command against the system, there may still end up being a front door solution which you should consider using first, but it may be necessary or important to do interaction based testing. Just my thoughts though.
Am I using Verify incorrectly?
You are using the Verify() method correctly, it just doesn't support the scenario you are using it for.
Is there a better way of using Moq to avoid this situation?
I don't think Moq is currently implemented to handle this scenario.
Hope this helps,
Derek Greer
http://derekgreer.lostechies.com
http://aspiringcraftsman.com
#derekgreer
First, you can avoid the conflict between Moq and MSpec by declaring
using Machine.Specifications;
using Moq;
using It = Machine.Specifications.It;
Then you'll only need to prefix with Moq. when you want to use Moq's It, for example Moq.It.IsAny<>().
Onto your question.
Note: This is not the original answer but an edited one after the OP added some real example code to the question
I've been trying out your sample code and I think it's got more to do with MSpec than Moq. Apparently (and I didn't know this either), when you modify the state of your SUT (System Under Test) inside an It delegate the changes gets remembered. What is happening now is:
Because delegate is run
It delegates are run, one after the other. If one changes the state, the following It will never see the set up in the Because. Hence your failed test.
I've tried marking your spec with the SetupForEachSpecificationAttribute:
[Subject(typeof(object)), SetupForEachSpecification]
public class When_Testing
{
// Something, Something, something...
}
The attribute does as its name says: It will run your Establish and Because before every It. Adding the attribute made the spec behave as expected: 3 Successes, one fail (the verification that with Var = "two").
Would the SetupForEachSpecificationAttribute solve your problem or is resetting after every It not acceptable for your tests?
FYI: I'm using Moq v4.0.10827.0 and MSpec v0.4.9.0
Free tip #2: If you're testing ASP.NET MVC apps with Mspec you might want to take a look at James Broome's MSpec extensions for MVC

Dependency injection - need larger example?

i'm looking for a larger example of dependency injection and how it can be implemented. If class A depends on class B and passes a reference of class C to B's constructor, must not class A also take a reference to class C in it's constructor? This means that the main method in the application should create all classes really, which sounds wierd?
I understand that using DI frameworks we can have it in XML files somehow, but that sounds like it could be hard to quickly see what type that really is instanciated? Especially if it a very large application.
You are correct and each DI framework has a different way of managing it.
Some use attributes on the properties etc to denote dependency and then "automagically" supply an instance of the correct type, while others (say castle windsor for .net) allow xml configuration, fluent or other methods for "wiring up" the dependency graph.
Also no, class A takes a built reference to an instance of B which was built using an instance of C. A needs to know nothing about C unless exposed via B.
public class C { }
public class B { public B(C c) { ... }}
public class A { public A(B b) { ... }}
// manual wireup
C c = new C();
B b = new B(c);
A a = new A(b);
// DI framework
InversionOfControlContainer container = new InversionOfControlContainer(... some configuration);
A a = container.ResolveInstanceOf<A>();
// container dynamically resolves the dependencies of A.
// it doesnt matter if the dependency chain on A is 100 classes long or 3.
// you need an instance of A and it will give you one.
Hope that helps.
to answer your question about classes A,B,and C, A only needs a reference to B.
Most DI frameworks do not require you to use XML for configuration. In fact, many people prefer not to use it. You can explicitly set things up in code, or use some kind of conventions or attributes for the container to infer what objects should fulfil dependencies.
Most DI frameworks have a facility for "lazy loading" to avoid the creation of every single class up front. Or you could inject your own "factory or builder" objects to create things closer to the time when they will be used
You've not said what language you are using. My example below is in C# using the Unity container. (obviously normally you would use interfaces rather than concrete types):
container = new UnityContainer();
container.RegisterType<C>();
container.RegisterType<B>();
A a = container.Resolve<A>();
here's a few examples from the PHP Language, hope this helps you understand
class Users
{
var $Database;
public function __construct(Database $DB)
{
$this->Database = $DB;
}
}
$Database = Database::getInstance();
$Users = new Users($Database);
From this example the new keyword is used in the method getInstance(), you can also do
$Users = new Users(Database::getInstance());
Or another way to tackle this is
class Users
{
/*Dependencies*/
private $database,$fileWriter;
public function addDependency($Name,$Object)
{
$this->$Name = $Object;
return $this;
}
}
$Users = new Users();
$Users->addDependency('database',new Database)->addDependency('fileWriter',new FileWriter);
Update:
to be honest, I never use Dependency Injection as all its doing is passing objects into classes to create a local scope.
I tend to create a global entity, and store objects within that so there only ever stored in 1 variable.
Let me show you a small example:
abstract class Registry
{
static $objects = array();
public function get($name)
{
return isset(self::$objects[$name]) ? self::$objects[$name] : null;
}
public function set($name,$object)
{
self::$objects[$name] = $object;
}
}
Ok the beauty of this type of class is
its very lightweight
it has a global scope
you can store anything such as resources
When your system loads up and your including and initializing all your objects you can just store them in here like so:
Registry::add('Database',new Database());
Registry::add('Reporter',new Reporter());
Where ever you are within your runtime you can just use this like a global variable:
class Users
{
public function getUserById($id)
{
$query = "SELECT * FROM users WHERE user_id = :id";
$resource = Registry::get("Database")->prepare($query);
$resource->bindParam(':id',$id,PDO::PARAM_INT);
if($resource->execute())
{
//etc
}else
{
Registry::get('Reporter')->Add("Unable to select getUserById");
}
}
}
i see this way of object passing is much cleaner
If anybody is still looking for a good example which shows DI without IoC Containers (poor man's DI) and also with IoC Container (Unity in this example) and registering the types in code and also in XML you can check this out: https://dannyvanderkraan.wordpress.com/2015/06/15/real-world-example-of-dependeny-injection/

StructureMap 202 - Why?

OK, I'm trying to set a property on a type I'm registering with SM.
Here's the code from the registry in one of my components. This
registry is being added during the configuration from a console app.
When I try to access the EndorsementSpecs property of the instance
AutoMandatoryEndorsementAggregator object, I get the 202. What's
interesting is that I can call
GetAllInstances>() from my
console app and it resolves just fine. Is there something about
accessing this code from within OnCreation that is causing the 202? I
can see everything I expect in WhatDoIHave(). I've also tried a TypeInterceptor with the same results.
//register all open generics
cfg.ConnectImplementationsToTypesClosing(typeof
(MandatoryEndorsementSpecBase<>));
ForSingletonOf<IMandatoryEndorsementAggregator<AutoPolicy>>()
.Use<AutoMandatoryEndorsementAggregator>()
.OnCreation((context, x) =>
{
var specs =
context.GetAllInstances<MandatoryEndorsementSpecBase<AutoPolicy>>();
x.EndorsementSpecs = specs;
})
;
Sorry to deflect your real questions, but are you just trying to inject all instances of MandatoryEndorsementSpecBase into AutoMandatoryEndorsementAggregatory?
If so, you can probably get away with just making it a constructor parameter so that they are all automatically injected.
public AutoMandatoryEndorsementAggregatory(MandatoryEndorsementSpecBase<AutoPolicy>[] endorsementSpecs){
EndorsementSpecs = endorsementSpecs;
}

ASP.NET MVC tests with MSpec. Is this correct or needs refactoring?

I'm new to MSpec and would like to know if the way I wrote my test for ASP.NET MVC is correct. The test passes but I don't really like the way it's written and it seems awkward. I'm certainly missing something.
public class AccountControllerTests3
{
protected static AccountController controller;
static IFormsAuthenticationService formsService;
static IMembershipService membershipService;
protected static ActionResult result;
protected static LogOnModel model;
Establish context = () =>
{
var controllerBuilder = new TestControllerBuilder();
formsService = MockRepository.GenerateStub<IFormsAuthenticationService>();
membershipService = MockRepository.GenerateStub<IMembershipService>();
model = MockRepository.GenerateStub<LogOnModel>();
controller =
controllerBuilder.CreateController<AccountController>(new object[]
{
formsService,
membershipService
});
};
Because user_logs = () =>
{
bool rememberMe = false;
membershipService.Stub(
x => x.ValidateUser("bdd", "mspec")).Return(true);
formsService.Stub(x => x.SignIn("bdd", rememberMe));
controller.ModelState.IsValid.ShouldBeTrue();
};
}
[Subject(typeof(AccountController), "LogInTests")]
public class When_logging_into_application_with_good_login_and_password : AccountControllerTests3
{
private It user_should_be_redirected_to_the_home_page = () =>
{
model.UserName = "bdd";
model.Password = "mspec";
result = controller.LogOn(model, string.Empty);
result.AssertActionRedirect().ToAction<HomeController>(
x => x.Index());
};
}
[Subject(typeof(AccountController), "LogInTests")]
public class When_logging_into_application_with_bad_login_and_password : AccountControllerTests3
{
It The_error_message_should_be_shown = () =>
{
model.UserName = "BAD";
model.Password = "BAD";
result = controller.LogOn(model, string.Empty);
controller.ModelState[""].Errors[0].ErrorMessage.ShouldEqual(
"The user name or password provided is incorrect.");
};
}
Thanks in advance,
Thomas
One of my goals when I write tests with MSpec is to get the "Assert" or the "It" down to one line. MSpec is not like NUnit in that it only executes the Context (made up of the Establish clauses from the current class and all base classes and the Because clause) once followed by all of the Specifications (It clauses).
This is designed explicitly to force you to not perform any behavior in the It clauses, but rather observe it.
What you're actually doing here is using MSpec like NUnit. Try and rewrite the tests in a single class (using no inheritance). Work backwards... in the It, place a single line that asserts what you want to assert. Perhaps the AssertRedirect. In the Because, try and put a single line that causes the observations to be observable. This would probably be your call to the controller's logon method. Finally, in the "Establish context" you'd want to put everything else.
After a while, you may want to pull some of the things in the Establish context only into a base class, but in doing so, be sure that your entire subclass stands alone in terms of understanding. A reader shouldn't need to read the base class in order to understand what the actual spec is doing. It's ok to hide ceremonial implementation details, but be sure to hide them behind descriptive method names.
There's another line I'm not sure about:
controller.ModelState.IsValid.ShouldBeTrue();
If this is a test, it should probably be in its own It clause. Though really, do you want to test this? What are you testing here? Shouldn't your controller take an action based on whether or not the model is valid? Shouldn't the result of that action be observable (validation error instead of login error). I just wonder if you really need to test this.
A few other things to check out, first for styling with R#, it seems your tests are falling victim to R#'s defaults. I posted about how to fight this here:
http://codebetter.com/blogs/aaron.jensen/archive/2008/10/19/getting-resharper-and-vs-to-play-nice-with-mspec.aspx
Also, James Broome has some nice MVC MSpec extensions that are worth checking out:
http://jamesbroo.me/introducing-machinespecificationsmvc/
Good luck and Enjoy! Feel free to ping me on twitter if you have any other unrelated questions.
Here's a remark: instead of using CreateController method use InitializeController, because it is compile-time safer and refactor friendlier.
Instead of:
controller = controllerBuilder.CreateController<AccountController>(
new object[] { formsService, membershipService });
Do:
controller = new AccountController(formsService, membershipService);
controllerBuilder.InitializeController(controller);
The first will still compile if you change the controller constructor arguments and it will blow at runtime, while the second will generate a compile-time error.

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