Error: stack overflow when RequireExplicitMapping = true

[pmatrosov]

Hi! This code generates StackOverlowException while calling method Compile() on versions 7.2.0 , 7.3.0 and 7.4-pre:

using Mapster;

var config = new TypeAdapterConfig
{
    RequireExplicitMapping = true, // comment this to remove StackOverlowException
    RequireDestinationMemberSource = true
};
config.NewConfig<Source, Destination>()/*.MaxDepth(10)*/;
config.Compile(); // StackOverlowException here

public class Source
{
    public string? Identifier { get; set; }
    public Source[]? Inner { get; set; }
}

public class Destination
{
    public string? Identifier { get; set; }
    public Destination[]? Inner { get; set; }
}

I found two workarounds to avoid this problem:

• remove "RequireExplicitMapping = true" at TypeAdapterConfig initialization
• set MaxDepth for mapping confuguration (see commented example above)

But both solutions are not suitable for me. Is this behavior a bug and how else can it be avoided?

[andrerav]

Can you explain what you expect to happen here?

[pmatrosov]

I expect no exception when using RequireExplicitMapping=true (I don't understand why it has an effect?) and unlimited nesting depth of Source class instance. All Source objects are unique in my case.

[thomas-hockings-cs]

I've also just come across this issue. When RequireExplicitMapping is true a stack overflow exception occurs with a circular reference during compile. The only solution is to use MaxDepth in your mapper because PreserveReference(true) has no effect.

It took me a while to figure this out because it doesn't appear to be documented that circular references are an issue when RequireExplicitMapping = true and it didn't seem like I was in a situation that would require MaxDepth.

I would much prefer to not have to use MaxDepth when RequireExplicitMapping = true.