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Unit Testing Marten

I'm putting together an implementation of IdentityServer4, using PostgreSQL as the database, Marten as the ORM, and GraphQL as the API. So far, it's working great at runtime. However, I'm also trying to get unit tests in place, and am running into an issue. I have a custom implementation of IdentityServer4's IClientStore interface, where the implementation of the FindClientByIdAsync method looks thus:
public async Task<Client> FindClientByIdAsync(string clientId)
{
var client = await _documentSession.Query<dbe.Client>().FirstOrDefaultAsync(c => c.ClientId == clientId);
return _mapper.Map<Client>(client); // AutoMapper conversion call
}
This works great at runtime. However, I have the following test that I'm trying to put in place to exorcise this code:
[Fact]
public async Task FindClientByIdReturnsClient()
{
var clients = new []
{
new dbe.Client
{
ClientId = "123"
}
}.AsQueryable();
var queryable = new MartenQueryable<dbe.Client>(clients.Provider);
// _documentSession is a Moq Mock
_documentSession.Setup(x => x.Query<dbe.Client>()).Returns(queryable);
var store = new ClientStore(_documentSession.Object, _mapper);
var result = await store.FindClientByIdAsync("123");
Assert.NotNull(result);
Assert.Equal("123", result.ClientId);
}
The error I get happens when the test tries to execute the FindClientByIdAsync method:
System.InvalidCastException : Unable to cast object of type 'System.Linq.EnumerableQuery`1[StaticSphere.Persona.Data.Entities.Client]' to type 'Marten.Linq.IMartenQueryable'.
If anyone is familiar with Marten can could provide some insight, that would be great! I've done my Google time, and haven't found anything concrete on the subject.

A quote from the creator of Marten which could be relevant here (context):
You can mock a bit of IDocumentSession (Load, Store, SaveChanges,
maybe query by compiled query), but you’re gonna be in a world of hurt
if you try to mock the Linq support.
So one solution would be to do integration tests for which you can find some code from the official Marten's repository or here.

FakeItEasy not verifying call for Full Framework SignalR test

I have a simple hub that I am trying to write a test for with FakeItEasy and the verification of calling the client is not passing. I have the example working in a separate project that uses MOQ and XUnit.
public interface IScheduleHubClientContract
{
void UpdateToCheckedIn(string id);
}
public void UpdateToCheckedIn_Should_Broadcast_Id()
{
var hub = new ScheduleHub();
var clients = A.Fake<IHubCallerConnectionContext<dynamic>>();
var all = A.Fake<IScheduleHubClientContract>();
var id= "123456789";
hub.Clients = clients;
A.CallTo(() => all.UpdateToCheckedIn(A<string>.Ignored)).MustHaveHappened();
A.CallTo(() => clients.All).Returns(all);
hub.UpdateToCheckedIn(id);
}
I'm using Fixie as the Unit Test Framework and it reports:
FakeItEasy.ExpectationException:
Expected to find it once or more but no calls were made to the fake object.
The sample below works in XUnit & MOQ:
public interface IScheduleClientContract
{
void UpdateToCheckedIn(string id);
}
[Fact]
public void UpdateToCheckedIn_Should_Broadcast_Id()
{
var hub = new ScheduleHub();
var clients = new Mock<IHubCallerConnectionContext<dynamic>>();
var all = new Mock<IScheduleClientContract>();
hub.Clients = clients.Object;
all.Setup(m=>m.UpdateToCheckedIn(It.IsAny<string>())).Verifiable();
clients.Setup(m => m.All).Returns(all.Object);
hub.UpdateToCheckedIn("id");
all.VerifyAll();
}
I'm not sure what I've missed in the conversion?

You're doing some steps in a weird (it looks to me, without seeing the innards of your classes) order, and I believe that's the problem.
I think your key problem is that you're attempting to verify that all.UpdateToCheckedIn must have happened before even calling hub.UpdateToCheckedIn. (I don't know for sure that hub.UpdateToCheckedIn calls all.UpdateToCheckedIn, but it sounds reasonable.
There's another problem, where you configure clients.Setup to return all.Object, which happens after you assert the call to all.UpdateToCheckedIn. I'm not sure whether that's necessary or not, but thought I'd mention it.
The usual ordering is
arrange the fakes (and whatever else you need)
act, but exercising the system under test (hub)
assert that expected actions were taken on the fakes (or whatever other conditions you deem necessary for success)
I would have expected to see something more like
// Arrange the fakes
var all = A.Fake<IScheduleHubClientContract>();
var clients = A.Fake<IHubCallerConnectionContext<dynamic>>();
A.CallTo(() => clients.All).Returns(all); // if All has a getter, this could be clients.All = all
// … and arrange the system under test
var hub = new ScheduleHub();
hub.Clients = clients;
// Act, by exercising the system under test
var id = "123456789";
hub.UpdateToCheckedIn(id);
// Assert - verify that the expected calls were made to the Fakes
A.CallTo(() => all.UpdateToCheckedIn(A<string>.Ignored)).MustHaveHappened();

Unit testing service that requires ODataQueryOptions

In attempts to do some test-driven-development, I've created the most basic, buildable method:
public class NoteService : INoteService
{
public IEnumerable<Annotation> GetNotes(ODataQueryOptions oDataQueryOptions)
{
return new List<Annotation>();
}
}
When trying to unit test it, it seems impossible to create an instance of ODataQueryOptions:
[TestFixture]
public class NoteServiceTests
{
[Test]
public void GetNotes_Returns_IEnumerable_Of_Notes()
{
var sut = new NoteService();
var queryOptions = new ODataQueryOptions(new ODataQueryContext(new EdmCoreModel(), new EdmCollectionType())// new new new etc??
Assert.That(() => sut.GetNotes(options), Is.InstanceOf<IEnumerable<Annotation>>());
}
}
How do you create a simple instance of the object ODataQueryOptions in order to inject it for unit tests?

Will this work?
var request = new HttpRequestMessage(HttpMethod.Get, "");
var context = new ODataQueryContext(EdmCoreModel.Instance, typeof(int));
var options = new ODataQueryOptions(context, request);

I wanted to do something similar and found a workable solution:
My use case
I have a web service that passes OData query parameters down to our CosmosDB document client which translates them into a CosmosDB SQL query.
I wanted a way to write integration tests directly on the CosmosDB client without having to make outgoing calls to other downstream services.
Approaches
Tried mocking ODataQueryParameters using Moq but because it's a class and not an interface, Moq can't properly instantiate all of the properties that I need
Tried instantiating one directly, but outside of an MVC application this is extremely difficult to build the required EdmModel.
Wondered if there is a way to do it without constructing an EdmModel?
I finally figured out a way to do it with the following:
This may not solve every use case, but here's the solution that I landed on for my needs:
public static class ODataQueryOptionsBuilder
{
private static WebApplicationFactory<TEntryPoint> _app =
new WebApplicationFactory<TEntryPoint>();
public static ODataQueryOptions<T> Build<T>(
string queryString)
where T : class
{
var httpContext = new DefaultHttpContext();
httpContext.Request.QueryString = new QueryString(queryString);
httpContext.RequestServices = _app.Services;
var modelBuilder = new ODataConventionModelBuilder();
modelBuilder.EntityType<T>();
var model = modelBuilder.GetEdmModel();
var context = new ODataQueryContext(
model,
typeof(T),
new Microsoft.AspNet.OData.Routing.ODataPath());
return new ODataQueryOptions<T>(context, httpContext.Request);
}
}
Conclusion
I realized that all I needed to get the ODataQueryOptions was a test server that was set up exactly like my web service. Once I realized that, the solution was simple. Use WebApplicationFactory to create the test server, and then allow OData to use the IServiceProvider from that application to build the ODataQueryOptions that I needed.
Drawbacks
Realize that this solution is as performant as your TEntryPoint, so if your application takes a long time to start up, this will cause unit/integration tests to take a long time to run.

Using Moq to verify a Prism event subscription fails

I am using the Prism framework together with Moq. I am trying to verify that the AlarmService subscribes to an event in the constructor but I am getting an exception that this is not supported.
How else can I verify this?
This is my testMethod:
public void TestMethod()
{
var mockMachineDataService = new Mock<IMachineDataService<AlarmDto>>();
var mockAggregator = new Mock<IEventAggregator>();
var mockEvent = new Mock<MachineMessageReceivedEvent>();
mockAggregator.Setup(x => x.GetEvent<MachineMessageReceivedEvent>()).Returns(mockEvent.Object);
var alarmService = new AlarmService(mockAggregator.Object, mockMachineDataService.Object);
Assert.IsNotNull(alarmService);
mockAggregator.VerifyAll();
mockEvent.Verify(x => x.Subscribe(It.IsAny<Action<MachineMessage>>(), It.IsAny<ThreadOption>()));
}
When I am running this I get the following failure:
System.NotSupportedException: Invalid verify on a non-virtual (overridable in VB) member: x => x.Subscribe(It.IsAny<Action`1>(), It.IsAny<ThreadOption>())
I did have a look at this and split up the mockAggregator and mockEvent to get the above code, but it still fails.

I guess the problem was that the Subscribe method is overloaded and in the end calls another Subscribe method with more default options which is virtual. By changing the test to verify this virtual method I can verify that the subscribe method has been called.
[TestMethod]
public void TestConstructorSubscribesToMachineMessages()
{
var mockMachineDataService = new Mock<IMachineDataService<AlarmDto>>();
var mockAggregator = new Mock<IEventAggregator>();
var mockEvent = new Mock<MachineMessageReceivedEvent>();
mockAggregator.Setup(x => x.GetEvent<MachineMessageReceivedEvent>()).Returns(mockEvent.Object);
mockEvent.Setup(x => x.Subscribe(It.IsAny<Action<MachineMessage>>(), It.IsAny<ThreadOption>(), It.IsAny<bool>(), It.IsAny<Predicate<MachineMessage>>()));
var alarmService = new AlarmService(mockAggregator.Object, mockMachineDataService.Object);
Assert.IsNotNull(alarmService);
mockAggregator.VerifyAll();
mockEvent.VerifyAll();
}

You can only Mock/Verify a Virtual or an interface method. Looks like Subscribe is not a virtual method.
Moq (and few other frameworks) uses Castle Project's DynamicProxy to generate proxies on the fly at run-time so that members of an object can be intercepted without modifying the code of the class. That interception can only be done on public virtual and protected virtual methods.
See below URL for more information: http://www.castleproject.org/projects/dynamicproxy/
UPDATE: For the code that you can't modify you can use Shims available with Microsoft Fakes framework. Note: Its not a good practice to use Shims for your own code.
http://msdn.microsoft.com/en-us/library/hh549175.aspx
How can I verify that a Microsoft Fakes (beta) stub/shim was called (like AssertWasCalled in Rhino Mocks)?

Microsoft Shims with a WCF Service

I am attempting to follow this example and leverage a shim to remove the external dependency on a WCF service call which is called from the method I am executing the unit test on. Unlike the example, I generate my WCF client on the fly using code similar to this:
ChannelFactory<IReportBroker> factory = new ChannelFactory<IReportBroker>("ReportBrokerBasicHttpStreamed", new EndpointAddress(this.CurrentSecurityZoneConfigurationManager.ConfigurationSettings[Constants.ConfigurationKeys.ReportBrokerServiceUrl]));
IReportBroker proxy = factory.CreateChannel();
proxy.Execute(requestMessage))
How do I adapt that example to shim the proxy returned back by the CreateChannel method? I am assuming that in the ShimWCFService class, I need to add something like....
ShimChannelFactory<TService>.AllInstances.CreateChannel = (var1) => { return [instance of a mock object]};
However, I am unsure of how to associate a mock object of <TService> with that shim as the return value.

You need to shim the factory for every type parameter. Assume you have the three Service contracts 'IService0' 'IService1' and 'IService2'.
Then you need to setup the shims like this:
ShimChannelFactory<IService0>.AllInstances.CreateChannel = (_) => { return new Service0Mock(); }
ShimChannelFactory<IService1>.AllInstances.CreateChannel = (_) => { return new Service1Mock(); }
ShimChannelFactory<IService2>.AllInstances.CreateChannel = (_) => { return new Service2Mock(); }