Automapper on HotChocolate Optional types

[shidcordero]

Source/destination types

// Source
public class TagInput
{
    public int? Id { get; set; }
    public Optional<string> Name { get; set; }
    public Optional<int?> TagTypeId { get; set; }
}

// Destination
public class Tag 
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }
    public string Name { get; set; }
    public int TagTypeId { get; set; }
    public virtual TagType TagType { get; set; }
}

Mapping configuration

public class TagInputProfile : Profile
{
    public TagInputProfile()
    {
        CreateMap<TagInput, Tag>()
            .ForMember(dest => dest.Id, opt => opt.Condition(src => src.Id.HasValue))
            .ForMember(dest => dest.Name, opt => {
                opt.PreCondition(src => src.Name.HasValue);
                opt.MapFrom(src => src.Name.Value);
            })
            .ForMember(dest => dest.TagTypeId, opt => {
                opt.PreCondition(src => src.TagTypeId.HasValue);
                opt.MapFrom(src => src.TagTypeId.Value);
            })
            .EqualityComparison((d, s) => d.Id == s.Id)
            .ReverseMap();
    }
}

Version:

Automapper: 8.1.1
Automapper.Collection: 7.0.1
HotChocolate: 12.6.1
EF6

Expected behavior

To be able to map Optional type to the destination. Right now it just keeps throwing this error on run:

System.ArgumentException: 'Expression of type 'System.Int32' cannot be used for parameter of type 'System.Nullable`1[System.Int32]' of method 'HotChocolate.Optional`1[System.Nullable`1[System.Int32]] op_Implicit(System.Nullable`1[System.Int32])' (Parameter 'arg0')'

Note that only Nullable does not work. The string type is working since I did not enable nullable reference types. Even nullable reference type was enabled, its still throwing the same error. I am not sure what's causing the error. I actually expect the above mapping code to work since the precondition will only map those if .HasValue (if .HasValue is true of Optional, it means that the user pass a value on that field. Optional is used for partial updates). Once the precondition is valid, it will only map it to the value(for example if its Optional<int?> and .HasValue is true, it will map from .Value of Optional<int?> that means its int?).

Actual behavior

It throws the error above.

Steps to reproduce

Not sure if this is the correct step to reproduce but the error was thrown when new MapperConfiguration() was called on Startup.cs

var configuration = new MapperConfiguration(config =>
{
    config.AddCollectionMappers();
    config.AddMaps("Horsebee.API");
});

services.AddSingleton(sp => configuration.CreateMapper());

[lbargaoanu]

A repro would help. Make a gist that we can execute and see fail. That means the only reference must be to the latest AM. Everything else must be part of the gist.

[shidcordero]

here's a dotnet fiddle to replicate the issue https://dotnetfiddle.net/pmXTRE
Here's the gist also

[lbargaoanu]

That works with the latest AM.

[shidcordero]

@lbargaoanu it works great. Now the only issue I have is with Automapper.Collections still not supporting latest version of Automapper.