Replace invalid MapPropertyAttribute constructors with valid versions

[latonz]

• Marks MapPropertyattribute.ctor(string[], string[]) as obsolete
• Adds MapPropertyAttribute.ctor(string[], string)
• Adds MapPropertyAttribute.ctor(string, string[])

[onionhammer]

Why remove support for nested -> nested?

[latonz]

It was never really supported by Mapperly, therefore we removed the constructor.

[onionhammer]

What do you mean by 'supported'? meaning not working in every scenario and you didn't want to support it?

It was certainly semi functional (and still is, obsolete aside)

[latonz]

I don't know of an example which works as expected with nested => nested. Can you provide an example?

[onionhammer]

For this example, I was using it to map a new backend to our legacy API's shape

using Riok.Mapperly.Abstractions;

namespace APITwo;

public enum ProductType
{
    Test,
}

public class InputProduct
{
    public string? Name { get; set; }
    public required InputPartner Partner { get; set; }
    public InputProductMetadata? Metadata { get; set; }
    public ProductType Type { get; set; }
}

public class InputPartner
{
    /// <summary>
    /// The name of the partner
    /// </summary>
    public string? Name { get; set; }
    public string? Headquarters { get; set; }
    public string? Description { get; set; }
    public string? AreasServed { get; set; }
}

public class InputProductMetadata
{
    public string? ImageUrl { get; set; }

    public InputPartnerMetadata? PartnerMetadata { get; set; }
}

public class InputPartnerMetadata
{
    public string? Headquarters { get; set; }
}

// =======

public class OutputProduct
{
    public Guid Id { get; set; }

    public OutputPartnerMetadata? Partner { get; set; }

    public OutputProductDetails? Details { get; set; }
}

public class OutputPartnerMetadata
{
    public string? Headquarters { get; set; }
    public string? Name { get; set; }
    public string? Description { get; set; }
    public string? AreasServed { get; set; }
}

public class OutputProductDetails
{
    public string? Name { get; set; }
    public string? ImageUrl { get; set; }
    public ProductType Type { get; set; }
}

/// <summary>
/// Map domain models to output models
/// </summary>
[Mapper]
public static partial class TestMapper
{
    [MapProperty(
        nameof(InputProduct.Name),
        [nameof(OutputProduct.Details), nameof(OutputProduct.Details.Name)]
    )]
    [MapProperty(
        [nameof(InputProduct.Partner), nameof(InputProduct.Partner.Name)],
        [nameof(OutputProduct.Partner), nameof(OutputProduct.Partner.Name)]
    )]
    [MapProperty(nameof(InputProduct.Metadata), nameof(OutputProduct.Details))]
    [MapProperty(
        [nameof(InputProduct.Metadata), nameof(InputProduct.Metadata.PartnerMetadata)],
        nameof(OutputProduct.Partner)
    )]
    [MapProperty(
        nameof(InputProduct.Type),
        [nameof(OutputProduct.Details), nameof(OutputProduct.Details.Type)]
    )]
    public static partial OutputProduct ProductToOutputProduct(InputProduct product);
}

The above code generates this mapping:

        [global::System.CodeDom.Compiler.GeneratedCode("Riok.Mapperly", "4.0.0.0")]
        public static partial global::APITwo.OutputProduct ProductToOutputProduct(global::APITwo.InputProduct product)
        {
            var target = new global::APITwo.OutputProduct();
            if (product.Metadata?.PartnerMetadata != null)
            {
                target.Partner = MapToOutputPartnerMetadata(product.Metadata.PartnerMetadata);
            }
            else
            {
                target.Partner = null;
            }
           ///// These lines are added
            target.Partner ??= new global::APITwo.OutputPartnerMetadata();
            target.Partner.Name = product.Partner.Name;
           ////
            if (product.Metadata != null)
            {
                target.Details = MapToOutputProductDetails(product.Metadata);
            }
            else
            {
                target.Details = null;
            }
            target.Details ??= new global::APITwo.OutputProductDetails();
            target.Details.Name = product.Name;
            target.Details.Type = product.Type;
            return target;
        }

        [global::System.CodeDom.Compiler.GeneratedCode("Riok.Mapperly", "4.0.0.0")]
        private static global::APITwo.OutputPartnerMetadata MapToOutputPartnerMetadata(global::APITwo.InputPartnerMetadata source)
        {
            var target = new global::APITwo.OutputPartnerMetadata();
            target.Headquarters = source.Headquarters;
            return target;
        }

        [global::System.CodeDom.Compiler.GeneratedCode("Riok.Mapperly", "4.0.0.0")]
        private static global::APITwo.OutputProductDetails MapToOutputProductDetails(global::APITwo.InputProductMetadata source)
        {
            var target = new global::APITwo.OutputProductDetails();
            target.ImageUrl = source.ImageUrl;
            return target;
        }

[latonz]

Oh I see, thanks, I didn't even know that worked and it's completely untested 🙈 I thought I had tested it before deprecating it. I'll investigate further and consider removing the deprecation with 4.1.0. Sorry for the inconvenience.

[onionhammer]

Ok, thanks for considering that!