public void RandomNull() => Execute(attempts: 5, test: () => { // setup var iterations = 0; // generate element var onElement = MockWebElement.GetElement(new MockWebDriver(), MockBy.Positive()); // iterate while (onElement != null) { iterations++; onElement = MockWebElement.GetElement(new MockWebDriver(), MockBy.RandomNull()); } // assertion Assert.IsTrue(iterations > 0); });