Mapping 2 objects to poco - issue when mapping the other way

[ChristoGC]

I thought I would flag an issue I observed.

When following the example in https://github.com/MapsterMapper/Mapster/wiki/Custom-mapping Example 2: Mapping 2 objects to poco there seems to be an issue when reversing the mapping. Creating a new tuple from from a poco is fine, but updates do not work.

Example code

const bool ShowScript = true;

void Main()
{
	TypeAdapterConfig.GlobalSettings.Compiler = exp => exp.CompileWithDebugInfo();
	string script;

	// Tuple to POCO
	TypeAdapterConfig<(AuthorizationGroup authorizationGroup, GroupDetails groupDetails), GroupDM>
		.NewConfig()
			.Map(dest => dest, src => src.authorizationGroup)
			.Map(dest => dest, src => src.groupDetails);


	AuthorizationGroup authorizationGroup = new() { Description = "TEST" };
	GroupDetails groupDetails = new() { GroupId = 10 };

	if(ShowScript)
	{
		script = (authorizationGroup, groupDetails).BuildAdapter()
					.CreateMapExpression<GroupDM>()
					.ToScript();

		Console.WriteLine(script);

		script = (authorizationGroup, groupDetails).BuildAdapter()
					.CreateMapToTargetExpression<GroupDM>()
					.ToScript();

		Console.WriteLine(script);
	}

	// Lets create a new instance of GroupDM: Works
	var obj = (authorizationGroup, groupDetails).Adapt<GroupDM>();

	// Now lets update
	authorizationGroup.Description = "UPDATED TEST";
	groupDetails.GroupId = 50;

	// Now lets update GroupDM: Works
	(authorizationGroup, groupDetails).Adapt(obj);
	
	// POCO to Tuple
	TypeAdapterConfig<GroupDM, (AuthorizationGroup authorizationGroup, GroupDetails groupDetails)>
	.NewConfig()
		.Map(dest => dest.authorizationGroup, src => src)
		.Map(dest => dest.groupDetails, src => src);

	GroupDM groupDM = new() { Name = "Hello world", Description = "Jon Bon Jovi" };

	if (ShowScript)
	{
		script = groupDM.BuildAdapter()
					.CreateMapExpression<(AuthorizationGroup authorizationGroup, GroupDetails groupDetails)>()
					.ToScript();
	
		Console.WriteLine(script);
	
	
		script = groupDM.BuildAdapter()
					.CreateMapToTargetExpression<(AuthorizationGroup authorizationGroup, GroupDetails groupDetails)>()
					.ToScript();

		Console.WriteLine(script);
	}

	// Create a new instance of (AuthorizationGroup, GroupDetails): This works
	var tuple = groupDM.Adapt<(AuthorizationGroup authorizationGroup, GroupDetails groupDetails)>();

	// Now lets update poco
	groupDM.GroupId = 99;
	groupDM.Description = "Led Zep";
	
	//Now lets update tuple: Doesn't work
	groupDM.Adapt(tuple);
}

public class GroupDM 
{
	public int GroupId;
	public string Name { get; set; }
	public string Description { get; set; }
}

public class AuthorizationGroup
{
	public string Name { get; set; }
	public string Description { get; set; }
}

public class GroupDetails
{
	public int GroupId { get; set; }
}

The expression scripts produced suggest that CreateMapToTargetExpression on poco to tuple is incorrect as it is exactly the same as CreateMapExpression

// New: Tuple to POCO
public GroupDM Main(ValueTuple<AuthorizationGroup, GroupDetails> p1)
{
    return new GroupDM()
    {
        Name = p1.Item1.Name,
        Description = p1.Item1.Description,
        GroupId = p1.Item2.GroupId
    };
}

// Update: Tuple to POCO
public GroupDM Main(ValueTuple<AuthorizationGroup, GroupDetails> p1, GroupDM p2)
{
    GroupDM result = p2 ?? new GroupDM();
   
    result.Name = p1.Item1.Name;
    result.Description = p1.Item1.Description;
    result.GroupId = p1.Item2.GroupId;
    return result;
   
}

// New:  POCO to Tuple
public ValueTuple<AuthorizationGroup, GroupDetails> Main(GroupDM p1)
{
    return p1 == null ? default(ValueTuple<AuthorizationGroup, GroupDetails>) : new ValueTuple<AuthorizationGroup, GroupDetails>(p1 == null ? null : new AuthorizationGroup()
    {
        Name = p1.Name,
        Description = p1.Description
    }, p1 == null ? null : new GroupDetails() {GroupId = p1.GroupId});
}

// Update:  POCO to Tuple
public ValueTuple<AuthorizationGroup, GroupDetails> Main(GroupDM p1, ValueTuple<AuthorizationGroup, GroupDetails> p2)
{
    return p1 == null ? default(ValueTuple<AuthorizationGroup, GroupDetails>) : new ValueTuple<AuthorizationGroup, GroupDetails>(p1 == null ? null : new AuthorizationGroup()
    {
        Name = p1.Name,
        Description = p1.Description
    }, p1 == null ? null : new GroupDetails() {GroupId = p1.GroupId});
}

Thanks in advance,

Chris

[DocSvartz]

Hello, named tuple, not named before compile. then always == Tuple<type1, type2> with tipe1 item1, type2 item2. You mapping for name, but name Not achievable, including for reflection, and after compile. Name use only when development type helpers

[DocSvartz]

Hello @ChristoGC If You get This Result?

[TestMethod]
public void MappedNamedTuple()
{
    TypeAdapterConfig<GroupDM604, (AuthorizationGroup604 authorizationGroup, GroupDetails604 groupDetails)>
    .NewConfig()
    .Map(dest => dest.authorizationGroup, src => src)
    .Map(dest => dest.groupDetails, src => src);

    GroupDM604 groupDM = new() { Name = "Hello world", Description = "Jon Bon Jovi" };

    // Create a new instance of (AuthorizationGroup, GroupDetails): This works
    var tuple = groupDM.Adapt<(AuthorizationGroup604 authorizationGroup, GroupDetails604 groupDetails)>();

    // Now lets update poco
    groupDM.GroupId = 99;
    groupDM.Description = "Led Zep";

    //Now lets update tuple: Doesn't work
    groupDM.Adapt(tuple);

    tuple.groupDetails.GroupId.ShouldBe(99); // true
    tuple.authorizationGroup.Description.ShouldBe("Led Zep"); // true 
}