Question How to define an empty TestFixtureSource

I have a test fixture class that loads different prefabs and executes a series of tests on them.
I am using the TestFixtureSource attribute to parameterize the fixture.


In some cases, i need the TestFixtureSource property to return an empty enumeration (e.g: no tests should be executed).

When building asset bundles, we launch tests from the command line, using a particular category ("Villages").
The problem is that not all built asset bundles are actually associated to the given category, so my test fixture source "filters" them out, which will essentially return an empty enumeration.

*Once we move to 2019.x, we could launch individual tests from editor code but for now we are still on Unity 2018.4, so i don't have access to the latest UTF package. we rely on the built-in Unity test runner.

Example (simplified):

Code (CSharp):

1. [TestFixtureSource("VillagePrefabPaths")]
2. [Category("Villages")]
3. public class VillagePrefabTests
4. {
5.     public VillagePrefabTests(AssetPath villagePrefabPath)
6.     {
7.         this.villagePrefabPath = villagePrefabPath.path;
8.     }
9.  
10.     private static IEnumerable<AssetPath> VillagePrefabPaths
11.     {
12.         get
13.         {
14.             List<AssetPath> assetPaths = new List<AssetPath>();
15.  
16.             return assetPaths.ToArray();
17.         }
18.     }
19. }
20.  

This doesn't work, the test fixture fails to run with this error:
OneTimeSetUp: No suitable constructor was found

Is there any way to set this up ?