public virtual void before_each()
        {
            autoSubstitute = new AutoSubstitute();

            contextFinder = autoSubstitute.Resolve <IContextFinder>();

            runnableContextFinder = autoSubstitute.Resolve <RunnableContextFinder>();

            contextFinder.BuildContextCollection(somePath).Returns(someContextCollection);
        }
 // Unit tests need a constructor with injected dependencies
 public RunnableContextFinder(IContextFinder contextFinder)
 {
     this.contextFinder = contextFinder;
 }