Scala 2.13: derivedConfiguratedEncoder becomes unconfigured under some conditions

[Awethon]

I am encountering an issue with Circe's deriveConfiguredEncoder in a Scala 2.13 project, where the derived encoder does not respect the custom discriminator configuration under certain conditions. Despite configuring Circe to use a custom discriminator ("type") via Configuration.default.withDiscriminator("type"), the derived encoders for sealed trait implementations do not include this discriminator in the output JSON.

import io.circe.{Codec, Decoder, Encoder, HCursor, Json, JsonObject}
import io.circe.generic.extras.Configuration
import io.circe.generic.extras.semiauto.{deriveConfiguredCodec, deriveConfiguredDecoder, deriveConfiguredEncoder}
import io.circe.parser._
import io.circe.syntax.EncoderOps

 object Identifier {
    sealed trait Id

    object Id {
      case class InternalId(id: String) extends Id
    }
  }

object codecs {
  import io.circe.Encoder
  import io.circe.generic.extras.Configuration
  import io.circe.generic.extras.semiauto.deriveConfiguredEncoder

  implicit lazy val configuration: Configuration = Configuration.default.withDiscriminator("type")

  private def encoder1: Encoder[Identifier.Id.InternalId] = deriveConfiguredEncoder

  implicit def betterEncoder1: Encoder[Identifier.Id.InternalId] = encoder1(_)

  implicit def idEncoder: Encoder[Identifier.Id] = deriveConfiguredEncoder

}

println(codecs.idEncoder(Identifier.Id.InternalId("123456789")))

    // {
    //  "InternalId" : {
    //    "id" : "123456789"
    //  }
    //} was not equal to {
    //  "type" : "InternalId",
    //  "id" : "123456789",
    //}

scatie: https://scastie.scala-lang.org/MdeMaxnsRPOj6F56wCioWA

[Awethon]

One possible workaround is to use Encoder.AsObject instead of Encoder and encodeObject instead of apply.