private IEnumerable <LocalUserPrincipalModel> GetPrincipalHierarchy(LocalUserPrincipalModel principal)
{
IEnumerable <LocalUserPrincipalModel> result = new LocalUserPrincipalModel[] { principal };
foreach (LocalUserGroupMemberModel member in principal.UserGroupMemberships)
{
result = result.Concat(GetPrincipalHierarchy(member.Group.Principal));
}
return(result);
}