namespace MHS {
    interface ISpinner {
        public void spin(Vector3 value);
    }

    [Serializable]
    public SpinController { //we can instantiate this in a test
        public float speed;
        public Vector3 axis;

        private ISpinner spinner;
        public void setSpinController(ISpinController spinner) {
            this.spinner = spinner;
        }

        public void doStuffBasedOnTime(float time) {
            spinner.spin(time);
        }

    }

    public Spinner : GameBehavior, ISpinner { // we cannot instantiate this in a test
        public SpinController controller;

        void OnEnable() {
            controller.SetSpinController(this);
        }

        void Update() {
            controller.doStuffBasedOnTime(Time.deltaTime);
        }

        //ISpinner implementation:
        public void spin(Vector3 value) {
            transform.Rotate(value);
        }
    }
}

namespace MHS.Tests {
    [TestFixture]
    public class SpinnerTest {

    }

    [Test]
    public void objectSpinsBasedOnTimeAndAxis() {
        //arrange
        SpinController controller = ...;
        ISpinner spinner = ...;
        controller.speed = 5f;
        controller.axis = new Vector3(0,1,0);
        controller.SetSpinner(spinner);

        //act
        controller.doStuffBasedOnTime(0.02f);

        //assert
        Assert.AreEqual(spinner.rotation, controller.axis*controller.speed);
    }
}