C# unit testing question

Question

Does someone if the following code (idea, actually) is possible using xunit:

public class RepositoryTester {

   private IRepository repository;

   public RepositoryTester(IRepository repository) {
      this.repository = repository;
   )

   [Fact] // Analogue of [Test] in other test packages.
   void CanDoWhatever() {
      // Test code
   }
}

Now, if I attempt to run all unit test, it would fail as long as xunit attempts to create the object RepositoryTester by calling new RepositoryTester() (it invokes the constructor without parameters).

What I want to do can be equivalently expressed this way:

var tester1 = new RepositoryTester(new SQLRepository(...));
var tester2 = new RepositoryTester(new InMemoryRepository(...));

tester1. RUN_ALL_TESTS();
tester2. RUN_ALL_TESTS();

---

Does someone know if the following behavior is possible? (I really wish to use the same test package for every testable repository through it's interface).

Thank you

Answer 1

You can make RepositoryTester abstract, and have a derived class for each type of repository that creates an appropriate IRepository in a parameter-less constructor. The inherited test methods will be run for each concrete child class.