public void it_should_return_all_values_from_the_original_collection_except_the_values_contained_in_the_second_collection()
{
var secretUsers = new[] { "Paul", "Jhon" };
var allUsers = new DataRepositoryDummy().GetPeopleWithPets().ToList();
allUsers.Add(new Person { Age = 12, LanguagesSpoken = Enumerable.Empty<Language>(), Name = "Jhon" });
var q = allUsers.Select(x => x.Name).Distinct().Except(secretUsers);
q.Should().HaveCount(3);
q.Should().OnlyHaveUniqueItems();
// alternate example 1
var q1 = (from u in allUsers
from s in secretUsers
where u.Name == s
select u).Distinct();
var q11 = allUsers.Except(q1);
q11.Should().HaveCount(3);
q11.Should().OnlyHaveUniqueItems();
// alternate example 2 - does not work
//var q2 = (from u in allUsers
// from s in secretUsers
// where u.Name != s
// select u).Distinct();
//q2.Should().HaveCount(3);
//q2.Should().OnlyHaveUniqueItems();
}