public void TestCorrectIndexingOfCities() { const int readCitiesExpected = 10; var cities = new Cities(); Assert.AreEqual(readCitiesExpected, cities.ReadCities(CitiesTestFile));;; City from = cities.FindCity("Mumbai"); City to = cities.FindCity("Istanbul"); List <City> foundCities = cities.FindCitiesBetween(from, to); // verify that Index property is initialized int i = 0; foreach (var city in foundCities) { Assert.AreEqual(i, city.Index); i++; } }