问题
I have a class like below where using Fluent Nhibernate I am getting data from database
public class MyActualClass
{
public MyActualClass(ISessionFactory sessionFactory)
{
this.sessionFactory = sessionFactory;
}
public List<AnnualInformation> GetData()
{
using (session = sessionFactory.OpenSession())
{
var result = session.QueryOver<AnnualInformation>()
.SelectList(list => list
.Select(x => x.Id)
.Select(x => x.CreationDate)
.Select(x => x.AnnualAmount)
.Select(x => x.AnnualCurrency)
.Select(() => monthlyAlias.MonthlyAmount)
.Select(() => monthlyAlias.MonthlyCurrency)
.Select(() => shareAlias.CurrentSharevalue)
.Select(() => miscAlias.MarketValueAmount)
).Where(a => a.Id == 123456).List<AnnualInformation>();
}
}
}
I Have written unit test case for above method like below
public class MyTestClass
{
private static ISessionFactory sessionFactory;
private static ISession session;
public MyTestClass()
{
sessionFactory = A.Fake<ISessionFactory>();
session = A.Fake<ISession>();
A.CallTo(() => sessionFactory.OpenSession()).Returns(session);
}
[Fact]
public void MyTest()
{
var annualDetails =
new AnnualInformation
{
Id= 1,
AnnualCurrency= "string",
AnnualAmount= "Example"
}
var listOfAnnualInformation=
new List<AnnualInformation>
{
annualDetails
};
A.CallTo(session.QueryOver<AnnualInformation>()).WithReturnType<IList<AnnualInformation>>().Returns(listOfAnnualInformation);
var myInstance = new MyActualClass(sessionFactory);
myInstance.GetData();
}
}
Actually if you see below code
session.QueryOver() .SelectList(...
will return "result" in method GetData(). After that I am manipulating "result" datastructure to get Id, CreationDate, AnnualAmount, AnnualCurrency
Therefore it is very important that some value is returned from "result". My problem is the count of resulty is always 0.
I want the below line of code
A.CallTo(session.QueryOver()).WithReturnType>().Returns(listOfAnnualInformation);
to return a list with atleast one element. Now i believe i clarified my requirements
Please suggest what should be done here ?
回答1:
Based on the new code (which still doesn't quite compile - missing ;
, result
isn't returned from GetData
, and if it were, the return type of GetData
should be IList<AnnualInformation>
, but with those changes I was able to get a test to run) I can offer some commentary:
A.CallTo(session.QueryOver<AnnualInformation>()).WithReturnType<IList<AnnualInformation>>()
.Returns(listOfAnnualInformation);
Configures the object that comes back from calling session.QueryOver<AnnualInformation>()
. (Note there's no lambda here, so this line actually calls QueryOver
.)session
is a Fake, and so when you call QueryOver<AnnualInformation>()
on this line, it will return a new Fake IQueryOver
. The "WithReturnType…Returns…" configures the new Fake IQueryOver to return listOfAnnualInformation
when any method that returns a IList<AnnualInformation>
is called.
However, when Fakes' methods are called, unless they've been configured to do something different, they return a new object. So inside GetData
when you call QueryOver
, you get a different fake IQueryOver
, which has not been configured at all. That's one problem.
Second problem: the call to SelectList
will return yet another faked IQueryOver
.
We can work around all these things:
var aFakeQueryOver = A.Fake<IQueryOver<AnnualInformation, AnnualInformation>>();
A.CallTo(aFakeQueryOver).WithReturnType<IQueryOver<AnnualInformation, AnnualInformation>>()
.Returns(aFakeQueryOver);
A.CallTo(aFakeQueryOver).WithReturnType<IList<AnnualInformation>>()
.Returns(listOfAnnualInformation);
A.CallTo((() => session.QueryOver<AnnualInformation>())).Returns(aFakeQueryOver);
And now the faking behaves as we want. However, all we've done is short-circuit all the logic in GetData
, except to see that it uses the sessionFactory
to open a session, and then QueryOver
on that session. SelectList
and Where
and List
have all been bypassed.
My usual advice in this situation is to make your data access layer as thin as possible and to integration test it. Alternatively, I've seen people suggest having NHibernate use an in-memory MySql database. Still an integration test of sorts, but at least it's more isolated.
来源:https://stackoverflow.com/questions/34023487/how-do-i-test-extension-method-of-nhibernate-which-does-not-return-the-value-eve