public void TestChangePhoneNullEntry()
        {
            IPhonebookRepository numberBook = new PhonebookHostRepository();

            var actual = numberBook.ChangePhone(null, "+359883223344");
            var expected = numberBook.ChangePhone("+359899777235", "+359883223344");

            Assert.AreNotEqual(expected, actual);
        }
        public void TestAddPhoneNoEntries()
        {
            IPhonebookRepository numberBook = new PhonebookHostRepository();
            string [] numbers = new string []{
            "0899 777 235",
            "02 / 981 11 11",
            };

            var actual = numberBook.AddPhone("kalina", null);

            var  expected = numberBook.AddPhone("kalina", numbers);

            Assert.AreNotEqual(expected, actual);
        }
        public void TestListNegativeEntries()
        {
            IPhonebookRepository numberBook = new PhonebookHostRepository();
            string[] numbers = new string[]{
            "0899 777 235",
            "02 / 981 11 11",
            };

            var actual = numberBook.List(-1, 2);

            var expected = numberBook.List(1, 2);

            Assert.AreNotEqual(expected, actual);
        }
        public void TestListTooManyEntries()
        {
            IPhonebookRepository numberBook = new PhonebookHostRepository();

            var actual = numberBook.List(1, 2000);

            var expected = numberBook.List(1, 2);

            Assert.AreNotEqual(expected, actual);
        }