bypass a prefetchable in unit testing

on my constructor, I put a checker if this feature is available or not, using prefetchable.
 

public ModelTypeMaint()
{
    Helpers.PreferenceHelper.CheckFeatures();
}

Now, I have tried to run a unit test on this particular graph, unfortunately even though I’ve implemented a mock setup, It still reads the Prefetchable checker.

How do I bypass the prefetchable on the constructor?

Unit Test Code

private ModelTypeMaint PrepareGraph()
{
            SetupEnableDisable<ModelTypeMaint>();
            var graph = PXGraph.CreateInstance<ModelTypeMaint>();
            return graph;
}

[Fact]
public void Test_Description_ValidLength()
{
      ModelTypeMaint graph = PrepareGraph();

      ModelType type = (ModelType)graph.Caches[typeof(ModelType)].Insert(new ModelType
      {
                ModelCD = "UT00001",
                Description = "Model Type: UNIT 00001"
      });

      Assert.InRange(type.Description.Length, 5, 255);
}

Thank you.