TestScheduler not working like expected on subscribed property (w throttle) - c#

I'm pretty green with rx/ReactiveUi and want to write a xunit test using TestScheduler to check if the throttle for retrieving search suggestions is working properly.
The idea is to use the TestScheudler for the timing, change the value for the search-term property and check if an async method is called. Unfortunately the method is not called at the expected position (see attached code, especially the unit test).
What am I missing? Is the way I'm trying to test this a good way to go?
My view Model:
public class MyViewModel : ReactiveObject
{
public MyViewModel (IMyQueryHandler queryHandler)
{
...
// Type suggestions
this.SearchTerms = this.ObservableForProperty(x => x.SearchTerm)
.Throttle(SuggestionThrottle).Value();
this.SearchTerms.Subscribe(this.LoadSearchSuggestionsAsync);
...
}
internal async void LoadSearchSuggestionsAsync(string search)
{
...
this.SearchSuggestions = this.queryHandler.ExecuteQuery(...);
...
}
public IList<SearchSuggestion> SearchSuggestions
{
get { return this.searchSuggestions; }
set { this.RaiseAndSetIfChanged(ref this.searchSuggestions, value); }
}
...
}
My Unit Test (xunit):
...
public class TestFixture : ReactiveObject
{
public string SearchTerms { get { return this._searchTermsBackingField.Value; } }
public ObservableAsPropertyHelper<string> _searchTermsBackingField;
}
[Fact]
public void WillTryToLoadSearchSuggestionsAfterThrottleTime()
{
new TestScheduler().With(
sched =>
{
var fixture = new TestFixture();
var queryClient = Substitute.For<IMyQueryHandler>();
var caseSuggestions = new List<...> { ... }
queryClient.ExecuteQuery<...>(...).ReturnsForAnyArgs(...); // Nsubstitute
var vm = new MyViewModel(queryClient);
vm.SearchTerms.ToProperty(fixture, p => p.SearchTerms, out fixture._searchTermsBackingField);
sched.Schedule(() => vm.SearchTerm = "Tes");
sched.Schedule(MyViewModel.SuggestionThrottle, () => vm.SearchTerm = "Test");
sched.AdvanceBy(MyViewModel.SuggestionThrottle.Ticks);
sched.AdvanceBy(1);
// why is the method MyViewModel.LoadSearchSuggestionsAsync not called here (in debug)???
sched.AdvanceBy(1);
} // method gets called here...
}
...

Throttle doesn't set the scheduler, write Throttle(timespan, RxApp.MainThreadScheduler) instead

Related

NUnit use different objects as Test Cases

I am trying to write an Update Test for different products (which are classes in this case) and different time steps :
public class UpdateTest
{
private static Product ProductLastYear;
private static Product ProductTwoYearsAgo;
public UpdateTest(Product product)
{
var previousReleasedProducts = new Products();
ProductLastYear = previousReleasedProducts.GetProduct(Years.GetLastYear());
ProductTwoYearsAgo = previousReleasedProducts.GetProduct(Years.GetTwoYearsAgo());
}
Each product needs to be installed, and afterwards it is checked if the installation was successful (this is basically a pre-step before the Update). Right now, I am using two Tests for this:
[Test, Category("UpdateLastYear")), Order((int) NunitTestOrderEnum.Order.First)]
public void InstallPreviousReleasedProduct()
{
using (var controller = new BootstrapperController(ProductLastYear))
{
controller.Install();
}
var successfulInstallation = InstallationValidator.ValidateInstall(ProductLastYear);
Assert.That(successfulInstallation, Is.True);
}
[Test, Category("UpdateTwoYearsAgo"), Order((int) NunitTestOrderEnum.Order.First)]
public void InstallTwoYearsAgoProduct()
{
using (var controller = new BootstrapperController(ProductTwoYearsAgo))
{
controller.Install();
}
var successfulInstallation = InstallationValidator.ValidateInstall(ProductTwoYearsAgo);
Assert.That(successfulInstallation, Is.True);
}
Now, both tests have some code redundancy, which I would like to avoid. I was thinking about using TestCases for this, something like :
[TestCase(ProductLastYear), Category("UpdateLastYear"), Order((int) NunitTestOrderEnum.Order.First)]
[TestCase(ProductTwoYearsAgo), Category("UpdateTwoYearsAgo"), Order((int) NunitTestOrderEnum.Order.First)]
public void InstallPreProduct(Product product)
{
using (var controller = new BootstrapperController(product))
{
controller.Install();
}
var successfulInstallation = InstallationValidator.ValidateInstall(product);
Assert.That(successfulInstallation, Is.True);
}
Is something like this possible? I tried different Syntax for that approach, but it does not seem to work that easily.
You can only use compile-time constants within attributes. However your static fields are no constants.
You can use the TestCaseSource-attribute:
[TestCaseSource(nameof(ProvideTestcases))]
public void InstallPreProduct(Product product)
{
using (var controller = new BootstrapperController(product))
{
controller.Install();
}
var successfulInstallation = InstallationValidator.ValidateInstall(product);
Assert.That(successfulInstallation, Is.True);
}
public static IEnumerable<TestCaseData> ProvideTestcases()
{
yield return new TestCaseData(ProductLastYear).SetCategory("UpdateLastYear");
yield return new TestCaseData(ProductTwoYearsAgo).SetCategory("UpdateTwoYearsAgo");
}
However that assumes your static fields are already initialized, which isn't the case. So you need a static constructor for your testclass.
[TestFixture]
public UpdateTest
{
public static ProductLastYear;
public static ProductTwoYearsAgo;
static
{
ProductLastYear = ...;
ProductTwoYearsAgo = ...;
}
}
This is pretty much boilerplate for so little duplication. So it's a tradeoff if or of it not this is worth the afford.
Another opportunity is to introduce some static constant, like an enum that reflects the property to be used:
[TestCase(MyEnum.LastYear), Category("UpdateLastYear")]
[TestCase(MyEnum.TwoYearsAgo), Category("UpdateTwoYearsAgo")]
public void InstallPreProduct(MyEnum product)
{
var Product = product == MyEnum.LastYear ?
ProductLastYear :
ProductTwoYearsAgo ;
using (var controller = new BootstrapperController(product))
{
controller.Install();
}
var successfulInstallation = InstallationValidator.ValidateInstall(product);
Assert.That(successfulInstallation, Is.True);
}
An enum is a constant expression, so you can easily use it within the test-attributes.

NSubstitute and DbContext.Set<TEntity> Could not find a call to return from

I am trying to write some tests for an existing service we have. It uses the DbContext (In our case, named DatabaseContext) and the constructor looks like this:
public GenericOrderProvider(DatabaseContext context, IOrderHandler<T> orderHandler)
{
_orderHandler = orderHandler;
_context = context;
_dbSet = context.Set<T>();
}
As you can see, it's generic and sets the _dbSet when it's initialized.
I have this very simple method:
public Attempt<IQueryable<T>> List(params string[] includes)
{
var x = _dbSet.ToList();
return Attempt<IQueryable<T>>.Succeed(_dbSet.OrderBy(m => m.Order));
}
And I wrote this test:
[TestFixture]
public class ListShould
{
[Test]
public void ReturnList()
{
// Assemble
var services = GenericOrderProviderContext.GivenServices();
var provider = services.WhenCreateOrderProvider();
services.DatabaseContext.Set<Attribute>().ReturnsForAnyArgs(new List<Attribute>().ToDbSet());
//services.DatabaseContext.Attributes = new List<Attribute>().ToDbSet();
// Act
var result = provider.List();
// Assert
result.Failure.Should().BeFalse();
result.Result.Count().Should().Be(0);
}
}
When I run that test, I get the error:
NSubstitute.Exceptions.CouldNotSetReturnDueToNoLastCallException : Could not find a call to return from.
The trace specifically targets the line services.DatabaseContext.Set<Attribute>().ReturnsForAnyArgs(new List<Attribute>().ToDbSet()); but I have no idea how to fix it.
As far as I can tell, I am mapping to the right method.
For completeness, here is my test Contexts:
public class GenericOrderProviderContext: DatabaseContextContext<GenericOrderProviderContext>
{
public static GenericOrderProviderContext GivenServices() => new GenericOrderProviderContext();
public IGenericOrderProvider<Attribute> WhenCreateOrderProvider() =>
new GenericOrderProvider<Attribute>(DatabaseContext,
new OrderHandler<Attribute>(DatabaseContext));
public bool IsSequential(List<Attribute> models)
{
return !models.OrderBy(m => m.Order).Select(m => m.Order).Select((i, j) => i - j).Distinct().Skip(1).Any();
}
}
public class DatabaseContextContext<T> where T: DatabaseContextContext<T>
{
public DatabaseContext DatabaseContext;
protected DatabaseContextContext()
{
DatabaseContext = Substitute.For<DatabaseContext>();
}
}
Does anyone know what I can do to resolve this issue?

Override Autofixture customization setup

I've a class with several services injected in its constructor. I'm using Autofixture with xUnit.net and NSubstitute, and created an attribute to setup the global customization.
public class AutoDbDataAttribute : AutoDataAttribute
{
public AutoDbDataAttribute() : base(() => new Fixture().Customize(new AutoNSubstituteCustomization()))
{
}
public AutoDbDataAttribute(Type customizationType) : base(() =>
{
var customization = Activator.CreateInstance(customizationType) as ICustomization;
var fixture = new Fixture();
fixture.Customize(new AutoNSubstituteCustomization());
fixture.Customize(customization);
return fixture;
})
{
}
}
I also have a custom customization class that setups the common customization for the test methods in the same class.
public class RevenueProviderCustomization : ICustomization
{
public void Customize(IFixture fixture)
{
fixture.Register<IRevenueContextService>(() =>
{
var contextService = Substitute.For<IRevenueContextService>();
contextService.GetContext().Returns(fixture.Create<RevenueContext>());
return contextService;
});
fixture.Register<ICompanyService>(() =>
{
var companyService = Substitute.For<ICompanyService>();
companyService.Get(Arg.Any<Guid>()).Returns(fixture.Create<Company>());
return companyService;
});
}
}
Now, some of my tests depend on modifying specific properties in the objects returned by the services. So in some cases, I want to modify the RevenueContext and in some cases, I want to modify the Company data.
What I did was creating another object inside the test itself and modify the Returns of the service with the new object, like this:
[Theory]
[AutoDbData(typeof(RevenueProviderCustomization))]
public void ShouldReturnCompanyRevenue(RevenueProvider sut, Company company, [Frozen]IRevenueContextService contextService)
{
var fixture = new Fixture();
RevenueContext context = fixture.Build<RevenueContext>().With(c => c.DepartmentId, null).Create();
contextService.GetContext().Returns(context);
sut.GetRevenue().Should().Be(company.Revenue);
}
But this doesn't work. The RevenueContext from the RevenueProviderCustomization is still used.
Does anyone know how I can override the return from the service? I don't want to setup the fixture one by one in my test, so I was hoping to be able to create a 'general setup' and modify as needed according to the test case.
UPDATE 1
Trying the answer from Mark, I changed the test to
[Theory]
[AutoDbData(typeof(RevenueProviderCustomization))]
public void ShouldReturnCompanyRevenue([Frozen]IRevenueContextService contextService, [Frozen]Company company, RevenueProvider sut, RevenueContext context)
{
context.DepartmentId = null;
contextService.GetContext().Returns(context);
sut.GetRevenue().Should().Be(company.Revenue);
}
The problem is because the RevenueContext is called in the RevenueProvider constructor. So my modification to the DepartmentId happens after the call was made.
public RevenueProvider(IRevenueContextService contextService, ICompanyService companyService)
{
_contextService = contextService;
_companyService = companyService;
_company = GetCompany();
}
public double GetRevenue()
{
if (_hasDepartmentContext)
return _company.Departments.Single(d => d.Id == _departmentId).Revenue;
else
return _company.Revenue;
}
private Company GetCompany()
{
RevenueContext context = _contextService.GetContext();
if (context.DepartmentId.HasValue)
{
_hasDepartmentContext = true;
_departmentId = context.DepartmentId.Value;
}
return _companyService.Get(context.CompanyId);
}
Assuming that RevenueProvider essentially looks like this:
public class RevenueProvider
{
private readonly ICompanyService companySvc;
public RevenueProvider(ICompanyService companySvc)
{
this.companySvc = companySvc;
}
public object GetRevenue()
{
var company = this.companySvc.Get(Guid.Empty);
return company.Revenue;
}
}
Then the following test passes:
[Theory]
[AutoDbData(typeof(RevenueProviderCustomization))]
public void ShouldReturnCompanyRevenue(
[Frozen]ICompanyService companySvc,
RevenueProvider sut,
Company company)
{
companySvc.Get(Arg.Any<Guid>()).Returns(company);
var actual = sut.GetRevenue();
Assert.Equal(company.Revenue, actual);
}
This scenario is exactly what the [Frozen] attribute is designed to handle. The various attributes that AutoFixture defines are applied in the order of the arguments. This is by design, because it enables you to pull out a few values from the argument list before you freeze a type.
In the OP, [Frozen] is only applied after sut, which is the reason the configuration of the mock doesn't apply within the SUT.

How can I get StructureMap's AutoMocker to mock fake data?

I'm currently trying to implement StructureMap's AutoMocking functionality and I need help with getting the mocked .
I have a Test method as follows:
[Test]
public void DirctoryResult_Returns_Groups()
{
var autoMocker = new RhinoAutoMocker<GroupController>(MockMode.AAA);
GroupController controller = autoMocker.ClassUnderTest;
var directoryResult = controller.DirectoryResult("b");
var fundDirectoryViewModel = (FundDirectoryViewModel)directoryResult.ViewData.Model;
Assert.IsNotNull(fundDirectoryViewModel.Groups);
}
Currently the test is failing because fundDirectoryViewModel.Groups is null.
The real implementation of DirectoryResult is as follows:
private readonly IGroupService _groupService;
public PartialViewResult DirectoryResult(string query)
{
return PartialView(new FundDirectoryViewModel
{
Groups =_groupService.GetGroupsByQuery(query)
});
}
where _groupService.GetGroupsByQuery(query) uses an interface to IGroupRepository to read data from the database. Of course, I don't want my test to read data from the actual database, but can somebody tell me how to get mock data for it?
What do I need to do to get the AutoMocker to mock the fake data for me?
update:
for reference, this is the definition of GroupService & GroupRepository
public class GroupService : IGroupService
{
private readonly IGroupRepository _groupRepository;
public GroupService(IGroupRepository groupRepository)
{
_groupRepository = groupRepository;
}
public IList<CompanyGroupInfo> GetGroupsByQuery(string query)
{
return _groupRepository.GetGroupsByQuery(query);
}
}
public class GroupRepository : DataUniverseRepository, IGroupRepository
{
public GroupRepository(ISession session)
{
_session = session;
}
public IList<CompanyGroupInfo> GetGroupsByQuery(string query)
{
// dig into the database and return stuff with _session..
}
}
I've been informed that the question was wrong. Automocker doesn't mock data like that. It's up to me to specify the fake data with Rhino Mocks.
This works:
[Test]
public void DirctoryResult_Returns_Groups()
{
var service = autoMocker.Get<IGroupService>();
service.Expect(srv => srv.GetGroupsByQuery(Arg<string>.Is.Anything))
.Return(new List<CompanyGroupInfo>
{
new CompanyGroupInfo(),
new CompanyGroupInfo(),
new CompanyGroupInfo()
});
service.Replay();
var directoryResult = _controller.DirectoryResult("b");
var fundDirectoryViewModel = (FundDirectoryViewModel)directoryResult.ViewData.Model;
Assert.That(fundDirectoryViewModel.Groups.Count, Is.EqualTo(3));
service.AssertWasCalled(srv => srv.GetGroupsByQuery(Arg<string>.Is.Equal("b")));
}

Rhino Mocks Exception Expect #1 Actual #0 : Need assistance

I've have searched on this and it seems to be a catch all, unfortunately everything I've read doesn't help figure it out. Here is the class:
public interface IMockInterface
{
MockClass MockedMethod();
MockClass MockThis();
}
public class MockClass : IMockInterface
{
public virtual MockClass MockedMethod()
{
MockClass returnValue;
returnValue = new MockClass();
returnValue.SomeMessage = "Not mocked";
return returnValue;
}
public MockClass MockThis()
{
MockClass mock;
MockClass returnValue;
mock = new MockClass();
return mock.MockedMethod();
}
}
And the test:
public void MockTest_Internal()
{
MockClass mainClass;
MockClass returnedClass;
IMockInterface mockProvider;
mainClass = new MockClass();
mockProvider = repository.StrictMock<IMockInterface>();
Expect.Call(mockProvider.MockedMethod())
.Return(new MockClass { SomeMessage = "Mocked" });
repository.ReplayAll();
returnedClass = mainClass.MockThis();
provider.AssertWasCalled(item => item.MockedMethod());
Assert.IsTrue(returnedClass.SomeMessage == "Mocked");
}
And have also tried and doesn't work
But I keep getting this exception:
Rhino.Mocks.Exceptions.ExpectationViolationException:
IMockInterface.MockedMethod(); Expected #1, Actual #0
Now from what I've read this would suggest either the method was called with different than expected parameters OR the method was never called but was expected to be called. This isn't the case for the test.
Side Note: This is my first time really using Rhino.Mocks without some in house code so I am basically picking it up as I go. There could be something really stupid here...
This was the old test commented on, but is not what I should have been using:
public void MockTest_Internal()
{
MockClass mainClass;
MockClass returnedClass;
IMockInterface mockProvider;
mainClass = new MockClass();
var provider = MockRepository.GenerateStub<IMockInterface>();
provider.Stub(item => item.MockedMethod())
.Return(new MockClass { SomeMessage = "Mocked" });
returnedClass = mainClass.MockThis();
provider.AssertWasCalled(item => item.MockedMethod());
Assert.IsTrue(returnedClass.SomeMessage == "Mocked");
}
You're telling the mock framework to stub the MockedMethod class on the provider object, but you never inject the provider into the mainClass object to be used. It's not clear to me what you are trying to accomplish but if you want the mocked method to be called then it has to be called on the object on which the stub was set up.
If you define MockThis as below, I think you will find that it will work.
public MockClass MockThis(IMockInterface provider)
{
return provider.MockMethod();
}
The bottom line is that you get the exception because the method was never called on the provider, only on the mainClass object.
EDIT: Example
public class ClassUnderTest
{
private ProviderClass provider { get; set; }
public ClassUnderTest( ProviderClass provider )
{
this.Provider = provider;
}
public int DoOperation()
{
return this.Provider.ProviderOperation();
}
}
public class ProviderClass
{
private int value = 42;
public ProviderClass()
{
}
public virtual int ProviderOperation()
{
return this.value;
}
}
[TestMethod]
public void DoOperationTest()
{
ProviderClass mockProvider = MockRepository.GenerateMock<ProviderClass>();
mockProvider.Expect( mp => mp.ProviderOperation() ).Return( -1 );
ClassUnderTest target = new ClassUnderTest( mockProvider );
int expectedValue = -1;
int value = target.DoOperation();
Assert.AreEqual( expectedValue, value );
mockProvider.VerifyAllExpectations();
}
Normally the ProviderClass object would return 42 from the ProviderOperation method, but we've mocked it out and told it to return -1. When the ClassUnderTest DoOperation method is called, the mock provider object's ProviderOperation method is invoked and returns the mocked value of -1.
Hope this helps.
I usually get this error when a stubbed method is called with an object argument that I build in the test and in the tested code the object is built before calling that method. The solution is to use the Rhino.Mocks Matches().
Ex:
Arg<string>.Matches(s => s.Contains("some substring"))

Categories