I have the following class that I am attempting to test
public abstract class MyClass<TU> : where TU : class, IMyInterface
{
protected virtual void ShowMessage(string message)
{
// do some work
}
protected IList<int> Items { get; set; }
// do some more work
}
I am testing with rhino mocks and mstest.
I want to be able to test the ShowMessage virtual method of the abstract class. To do such, I will need to create an accessor that can access the protected method of the class.
I generate the accessor in to my test project without issue.
However it causes the following build error:
GenericArguments[0], 'TU', on '"Namepace of IMyInterface".IMyInterface`1[TU]' violates the constraint of type parameter 'TU'.
Any ideas as to why this may be occuring and how to resolve it?
Related
I've updated Specflow from the 3.0.225 to the 3.1.62 and I received the error Tests_Integration_MSTestAssemblyHooks: Cannot define more than one method with the AssemblyInitialize attribute inside an assembly.
The reason is obviously that I'd had the [AssemblyInitialize] attribute in my project already. How can I fix it?
The reason is that Specflow generates another file in the background which has the AssemblyInitialize/AssemblyCleanup hooks defined. In order to fix that one should use the hooks provided by Specflow, namely BeforeTestRun/AfterTestRun. Like this:
[Binding] // add the Binding attribute on the class with the assembly level hooks
public abstract class SeleniumTest
{
// it used to be [AssemblyInitialize]
[BeforeTestRun]
public static void AssemblyInitialize(/* note there is no TestContext parameter anymore */)
{
// ...
}
// it used to be [AssemblyCleanup]
[AfterTestRun]
public static void AssemblyCleanup()
{
// ...
}
}
I've come across an interesting error. I have two test files for my xamarin mobile application, both testing view models:
public class TestFirstViewModel : MvxIoCSupportingTest
{
public void AdditionalSetup() {
//Register services and dependencies here.
}
[Fact]
public TestMethod1() {
// Successful test code here.
}
}
That's in one file. In another file, I have:
public class TestSecondViewModel : MvxIoCSupportingTest
{
public void AdditionalSetup() {
//Register services and dependencies here, slightly different from first
}
[Fact]
public TestMethod2() {
// Successful test code here.
}
}
When I run these files individually (I'm using xunit), they work just fine. However, when I run them together, I get the following error on one of the test cases:
Result Message: Cirrious.CrossCore.Exceptions.MvxException : You cannot create more than one instance of MvxSingleton
Result StackTrace:
at Cirrious.CrossCore.Core.MvxSingleton`1..ctor()
at Cirrious.CrossCore.IoC.MvxSimpleIoCContainer..ctor(IMvxIocOptions options)
at Cirrious.CrossCore.IoC.MvxSimpleIoCContainer.Initialize(IMvxIocOptions options)
at Cirrious.MvvmCross.Test.Core.MvxIoCSupportingTest.ClearAll()
at Cirrious.MvvmCross.Test.Core.MvxIoCSupportingTest.Setup()
at Project.Test.TestFirstViewModel.TestMethod1() in ...
Can anyone tell me what's going on here?
The issue stems from the parallelization of XUnit without the option to do proper tear-down. You could diable parallelization in the AssemblyIndo.cs file in you test project by adding:
[assembly: CollectionBehavior(DisableTestParallelization = true)]
I ended up solving this question by changing testing frameworks. I had different ioc singleton initializations, because, well, they're different test cases and needed different inputs/mocks. Instead of using Xunit, I resorted to Nunit where their cache clearing was much more defined: Xunit doesn't exactly believe in setup and tear-down, so it made a test environment like this more difficult.
I fixed the issue by using the collection attribute.
[Collection("ViewModels")]
class ViewModelATest : BaseViewModelTest {
...
}
[Collection("ViewModels")]
class ViewModelBTest : BaseViewModelTest {
...
}
The base view model test class has the mock dispatcher and performs the singleton registrations in the additional setup method.
Each of my tests calls ClearAll() at the beginning.
I hade some success with setup things in a constructor and add this check:
public PaymentRepositoryTests()
{
if (MvxSingletonCache.Instance == null)
{
Setup();
}
//other registerings.
}`
Also I did implement the IDisposable Interface
public void Dispose()
{
ClearAll();
}
But tbh not sure how much impact that had..
It works ok with xunit
Copy MvxIocSupportingTest and Mvxtest in your xunit PCL project.
Modify MvxTest to remove the attributes and use a simple contructor:
public class MvxTest : MvxIoCSupportingTest
{
protected MockMvxViewDispatcher MockDispatcher { get; private set; }
public MvxTest()
{
Setup();
}
...
And in each of you test, derive from IClassFixture
public class TestRadiosApi : IClassFixture<MvxTest>
{
[Fact]
public async Task TestToken()
{
...
xunit will create the MvxTest class only once for all tests.
Since the interface is already on the diagram I would like to show inheritance reference explicitly. But I can't find how...
There is a bug in VS 2005 up to 2012 that won't allow it to work.
I have a work arround that might trick it into drawing the inheritance for interfaces.
Say your interface is called IMyInterface. You have to replace it with an abstract class implementing that interface and use it instead of your interface. The code would make use of the conditional compilation and will look like this:
//to generate class diagram, add 'CLSDIAGRAM' to the conditional symbols on the Build tab,
// or add '#define CLSDIAGRAM' at the top of this file
#if CLSDIAGRAM
#warning CLSDIAGRAM is defined and this build should be used only in the context of class diagram generation
//rename your interface by adding _
public interface IMyInterface_
{
int MyProperty { get; }
void MyMethod();
}
//this class will act as an interface in the class diagram ;)
public abstract class IMyInterface : IMyInterface_ // tricks other code into using the class instead
{
//fake implementation
public int MyProperty {
get { throw new NotImplementedException(); }
}
public void MyMethod()
{
throw new NotImplementedException();
}
}
#else
// this is the original interface
public interface IMyInterface {
int MyProperty { get; }
void MyMethod();
}
#endif
That's likely to show it as you wish.
In your case IMyInterface will become IMedicine.
Good day, I have a fairly simple question to experienced C# programmers. Basically, I would like to have an abstract base class that contains a function that relies on the values of child classes. I have tried code similar to the following, but the compiler complains that SomeVariable is null when SomeFunction() attempts to use it.
Base class:
public abstract class BaseClass
{
protected virtual SomeType SomeVariable;
public BaseClass()
{
this.SomeFunction();
}
protected void SomeFunction()
{
//DO SOMETHING WITH SomeVariable
}
}
A child class:
public class ChildClass:BaseClass
{
protected override SomeType SomeVariable=SomeValue;
}
Now I would expect that when I do:
ChildClass CC=new ChildClass();
A new instance of ChildClass should be made and CC would run its inherited SomeFunction using SomeValue. However, this is not what happens. The compiler complains that SomeVariable is null in BaseClass. Is what I want to do even possible in C#? I have used other managed languages that allow me to do such things, so I certain I am just making a simple mistake here.
Any help is greatly appreciated, thank you.
You got it almost right, but you need to use properties instead of variables:
public abstract class BaseClass {
protected SomeType SomeProperty {get; set}
public BaseClass() {
// You cannot call this.SomeFunction() here: the property is not initialized yet
}
protected void SomeFunction() {
//DO SOMETHING WITH SomeProperty
}
}
public class ChildClass:BaseClass {
public ChildClass() {
SomeProperty=SomeValue;
}
}
You cannot use FomeFunction in the constructor because SomeProperty has not been initialized by the derived class. Outside of constructor it's fine, though. In general, accessing virtual members in the constructor should be considered suspicious.
If you must pass values from derived classes to base class constructor, it's best to do it explicitly through parameters of a protected constructor.
I am creating an application in mvc3 and wondering how to deal with database data which is required for all application requests, some of them depends on a session, some of them depends on url pattern basically all data is in database.
Like to know best practice
What I do in my applications and consider to be the best practice is to load your common data to the ViewBag on the Controller constructor.
For every project, I have a DefaultController abstract class that extends Controller. So, every controller in the project must inherit from DefaultController, instead of Controller. In that class' constructor, I load all data common to the whole project, like so:
// DefaultController.cs
public abstract class DefaultController : Controller
{
protected IRepository Repo { get; private set; }
protected DefaultController(IRepository repo)
{
Repo = repo;
ViewBag.CurrentUser = GetLoggedInUser();
}
protected User GetLoggedInUser()
{
// your logic for retrieving the data here
}
}
// HomeController.cs
public class HomeController : DefaultController
{
public HomeController(IRepository repo) : base(repo)
{
}
// ... your action methods
}
That way you will always have the logged in user available in your views.
I do the same as #rdumont but with one exception: I create a CommonViewModel which I use to define all common properties that I use.
public class CommonViewModel
{
public string UserName {get;set;}
public string Extension {get;set; }
}
Declare a property in the base controller:
public abstract class BaseController : Controller
{
protected CommonViewModel Commons { get; private set; }
protected virtual void OnResultExecuting(ResultExecutingContext filterContext)
{
ViewBag.Commons = Commons;
}
}
By doing so I get everything almost typed. The only cast that I need to do is to cast ViewBag.Commons to the CommonViewModel.
Best is to avoid ViewBag at all.
See this answer, which details how to use Html.RenderAction() for that purpose:
Best way to show account information in layout file in MVC3
I'd suggest using a base ViewModel class.
So a base class with properties/functions which should be available at any point.