Is it possible in a C# testing framework to have my auto fac dependencies injected for me into my tests?

Question

Can Autofac inject dependencies into my test class?

Consider the test class (I've kept the example generic as I'll use whatever framework gives me this capability).

public class SimpleTest {

   private IService _service;

   public SimpleTest(IService service) 
   {
       _service = service;
   }

   public void TestMethod() {
   {
       // do something with service
   }
}

That IService type is provided by autofac. So now when I run my test method I want various dependencies coming from autofac to have been injected. I don't mind if it has to use field injection - I can make them public if necessary.

Maybe there is some kind of test runner I can register that can do this "preconfiguration"?

Does this snaswer your question? [Is it possible to use Dependency Injection with xUnit?](https://stackoverflow.com/questions/39131219/is-it-possible-to-use-dependency-injection-with-xunit) — canton7, Oct 22 '21 at 07:36
I didn't tag it as xunit.net... it's tagged as xunit (unit testing in general) but it seems that xunit is the only that's tried to implement this — Michael Wiles, Oct 22 '21 at 08:21
In the .NET world, "xUnit" invariably refers to the unit test framework with that name — canton7, Oct 22 '21 at 08:25

score 0 · Answer 1 · answered Oct 27 '21 at 09:34

Thanks for your responses.

I added a custom base class that does this for me...

Here is the code for MSTest (which is what I'm using).

 [TestInitialize]
 public void InjectAutofacDependencies()
 {
      var fieldInfos = this.GetType().GetFields(
         BindingFlags.DeclaredOnly |
         BindingFlags.NonPublic | BindingFlags.Instance);

      foreach (var fieldInfo in fieldInfos)
      {
          var resolveOptional = 
              _container.ResolveOptional(fieldInfo.FieldType);
          if (resolveOptional != null)
          {
               fieldInfo.SetValue(this, resolveOptional);
          }
      }
  }

I'd have preferred constructor injection but this will more than suffice.

Is it possible in a C# testing framework to have my auto fac dependencies injected for me into my tests?

1 Answers1