Comma-separated parsing does not work with sealed hierarchies

[paulpdaniels]

Consider the following:

import zio._
import zio.config._
import zio.config.magnolia._
import zio.config.typesafe._

sealed trait EnumConfig

object EnumConfig {
  case object One extends EnumConfig
  case object Two extends EnumConfig
  case object Three extends EnumConfig
}

case class OuterConfig(list: List[EnumConfig])

val outerConfig = DeriveConfig.deriveConfig[OuterConfig].nested("outer")

val hocon = """
outer {
  list = "One,Two,Three"
}
"""

val provider = ConfigProvider.fromHoconString(hocon, true)
Unsafe.unsafe { implicit u =>
  Runtime.default.unsafe.run(
  ZIO
    .config(outerConfig)
    .flatMap(c => ZIO.debug(c))
    .provide(Runtime.setConfigProvider(provider)))
}

Scastie: https://scastie.scala-lang.org/YzsMuk4iTzSNxqIg0fVv2w

Running this example will result in an error about the list field needing to be a constant. However, if you change the list: List[EnumConfig] to list: List[String] the resulting config is parsed correctly as a list of strings.

At the moment, I have only attempted this with typesafe so I'm not sure how it affects other providers