asp.net mvc - Automapper mapping list becomes 0

Question

I'm mapping a list to another list with Automapper, but it seems that my items are not copied.

Here is my code:

var roles = userRepo.GetRoles(null).ToList();
Mapper.CreateMap < List<Domain.Role>, List<Role>>();
var mappedRole = Mapper.Map<List<Domain.Role>, List<Role>>(roles); //the count is 0, list empty :(
Mapper.AssertConfigurationIsValid();

1. No exceptions were thrown.
2. All properties has the same names.

Domain.Role

public class Role
{
    public int RoleId { get; set; }
    public string RoleName { get; set; }
    public List<User> Users { get; set; }
}

Role

public class Role
{
    public int RoleId { get; set; }
    public string RoleName { get; set; }
}

Answer 1

Don't create maps between lists and array, only between the types:

Mapper.CreateMap<Domain.Role, Role>();

and then:

var mappedRole = Mapper.Map<List<Domain.Role>, List<Role>>(roles);

AutoMapper handles lists and arrays automatically.