Replace member value with different type

[jerone]

I have a member inside my class that is of a complex type (e.g. Func<ValueTask>) that I really don't care about its contents. I only care if the member has a value or not.

I cannot use IgnoreMember because I do care if it has a value. Same reason I cannot use ScrubMember.
It looks like TreatAsString is designed for something else.
I tried using MemberConverter but it will complain if I change it's type from something complex to let's say a string.
Custom converter seems overkill, because I only care about this one member, and would like to leave the rest of the class default.

Is there another solution I might have missed?

Pseudo example:

[Fact]
public Task Test()
{
    var obj = new {
		Member = "value",
		ComplexMember = (Func<ValueTask>) (() => ... })
	};
    return Verify(ojb);
}

Pseudo result:

{
    Member: value,
    ComplexMember: {
        Type: Func<ValueTask>,
        Target: Something.<>c__SomethingClass5_0,
        Method: System.Threading.Tasks.ValueTask ComplexMember()
    }
}

Wanted result:

{
    Member: value,
    ComplexMember: "has value" // Or `no value` when left empty.
}

[jerone]

I found a solution by using a custom converter.

I still think this is overkill and I much rather use MemberConverter with an option to change the PropertyType (same as the scrubber).

In the code below I used GetProperties() to get all properties and default back to build in serialization, because I have no control over the type (ISomeInterface in below code).

public class SomeConverter : WriteOnlyJsonConverter<ISomeInterface>
{
    public override void Write(VerifyJsonWriter writer, ISomeInterface value)
    {
        writer.WriteStartObject();

        var type = value.GetType();
        var props = type.GetTypeInfo().GetProperties(BindingFlags.Instance | BindingFlags.Public);
        foreach (var prop in props)
        {
            var val = prop.GetValue(value);
            if (prop.Name == nameof(ISomeInterface.SomeDelegate) && val is not null)
            {
                writer.WriteMember(value, "{some message}", prop.Name);
            }
            else
            {
                writer.WritePropertyName(prop.Name);
                writer.Serializer.Serialize(writer, val);
            }
        }

        writer.WriteEndObject();
    }
}

[jerone]

This will throw exception:

        VerifierSettings.MemberConverter(
            typeof(ISomeInterface),
            nameof(ISomeInterface.SomeDelegate),
            (target, value) => value is null ? null : "{some message}"
        );

Exception

System.InvalidCastException
Unable to cast object of type 'System.String' to type 'System.Delegate'.
   at VerifyTests.WriteOnlyJsonConverter`1.Write(VerifyJsonWriter writer, Object value) in /_/src/Verify/Serialization/WriteOnlyJsonConverterT.cs:line 7
   at VerifyTests.WriteOnlyJsonConverter.WriteJson(JsonWriter writer, Object value, JsonSerializer serializer) in /_/src/Verify/Serialization/WriteOnlyJsonConverter.cs:line 12
   at JsonSerializerInternalWriter.SerializeConvertible(JsonWriter writer, JsonConverter converter, Object value, JsonContract contract, JsonContainerContract collectionContract, JsonProperty containerProperty) in /_/src/Argon/Serialization/JsonSerializerInternalWriter.cs:line 538