Mapping not working as expected

[powerdude]

Hello all,

the following fails to generate a mapping file and I'm not sure why. Can anyone share any insights?

public class Source
{
    public ICollection<SourceSub> Subs { get; init; }
}

public class SourceSub
{
    public string Name { get; init; }
}

public class Target
{

    private List<TargetSub> subs = new List<TargetSub>();

    public IReadOnlyList<TargetSub> Subs
    {
        get => subs;
        private set => subs = value.ToList();
    }
}

public class TargetSub
{
    public string Name { get; set; }
}

[Mapper(IncludedMembers = MemberVisibility.All)]
public static partial class Mapper
{
    public static partial Target MapToTarget(Source source);
}

[TimothyMakkison]

Hey, thanks for the bug report.

This appears to be caused by the private field having the name subs. I'm guessing mapperly sees the matching private field and property and tries to map the source onto it.
It's a little peculiar because Mapperly should never try to map Subs to subs unless PropertyNameMappingStrategy.CaseInsensitive is being used, I'm not sure why this is happening and will look into a fix.

Note that this isn't unique to private member mapping, it can be replicated by creating two properties, one upper case, one lower case.

For the time being, try using underscore prefixes or different names for private fields if this occurs, sorry 🙏

Edit: Mapperly crashes on line 127 in MembersMappingBuilderContext as it attempts to add members to a dictionary.

Fix at #1077

[latonz]

Should be fixed in the latest release.