public void Test_Filter_Not_Null_3()
{
int[] arr = { 1, 2, 7, 5, 77, 47, 45, 56, 97, 107 };
IEnumerable <int> actual = FilterDigit.ByDigit(arr, 4);
CollectionAssert.AreEqual(new int[] { 47, 45 }, actual);
}
public void Test_Filter_Is_Null()
{
Assert.Throws <ArgumentNullException>(() => FilterDigit.ByDigit(null, 7));
}