public void FilterDigit_CorrectValuesPassed_WorksCorrectly(IList <int> initialList, int soughtDigit,
IList <int> expectedList)
{
IPredicate <int> predicate = new DigitInNumberPredicate(soughtDigit);
IList <int> actualList = NumericUtils.FilterDigit(initialList, predicate);
CollectionAssert.AreEqual(expectedList, actualList);
}