How to unflatten properties, ignored in other map? - automapper

Question

Sources for my destination are spitted in root dto and its child property:
public class Source {
public AccountSource {get;set;}
public string AccountKey {get;set;}
public string AccountPassword {get;set;}
}
public class AccountSource {
public Guid Id { get; set; }
public string Name { get; set; }
}
public class Dest
{
public Account Account { get; set; }
public class Account
{
public Guid Id { get; set; }
public string Name { get; set; }
public string Password { get; set; }
public string Key { get; set; }
}
}
At now I have such mapping:
CreateMap<Source, Dest>()
.ForPath(x => x.Account.Id, o => o.MapFrom(x => x.Account.Id))
.ForPath(x => x.Account.Name, o => o.MapFrom(x => x.Account.Name))
.ForPath(x => x.Account.Key, o => o.MapFrom(x => x.AccountKey))
.ForPath(x => x.Account.Password, o => o.MapFrom(x => x.AccountPassword));
CreateMap<AccountSource, Dest.Account>()
.ForAllMembers(x => x.Ignore());
but it have one issue: new members added to Dest.Account will be not validated.
If remove ForPath and just leave
CreateMap<Source, Dest>();
CreateMap<AccountSource, Dest.Account>();
than Password and Key are Unmapped, so I have to Ignore() them in such way CreateMap<AccountSource, Dest.Account>().ForMember(x => x.Password, x=> x.Ignore()).ForMember(x => x.Key, x=> x.Ignore()).
But then unflattening not working (props ignored absolutely, not only when account→account mapping occurred).

Answer 1

By default, ForPath will ignore Dest.Account, but you can always map it explicitly:
CreateMap<Source, Dest>()
.ForPath(d => d.Account.Key, o => o.MapFrom(s => s.AccountKey))
.ForPath(d => d.Account.Password, o => o.MapFrom(s => s.AccountPassword))
.ForMember(d => d.Account, o => o.MapFrom(s => s.Account));
CreateMap<AccountSource, Account>()
.ForMember(d => d.Password, o => o.Ignore())
.ForMember(d => d.Key, o => o.Ignore());

Answer 2

Found another solution:
CreateMap<Source, Dest>()
.ForMember(x => x.Account, o => o.MapFrom(x => x));
CreateMap<Source, Dest.Account>()
.ForMember(x => x.Id, o => o.MapFrom(x => x.AccountSource.Id))
.ForMember(x => x.Name, o => o.MapFrom(x => x.AccountSource.Name))
.ForMember(x => x.Password, o => o.MapFrom(x => x.AccountPassword))
.ForMember(x => x.Key, o => o.MapFrom(x => x.AccountKey));