Salat nested case class with scala 2.9.1

console.scala

rose@marzipan:~/workspace/salat (master)$ sbt
salat:master:0.0.8-SNAPSHOT> project salat-core
[info] Set current project to salat-core (in build file:/home/rose/workspace/salat/)
salat-core:master:0.0.8-SNAPSHOT> test:console

scala> import com.mongodb.casbah._
import com.mongodb.casbah._

scala> import com.novus.salat.grater
import com.novus.salat.grater

scala> import com.novus.salat.annotations._
import com.novus.salat.annotations._

scala> import com.novus.salat.global._
import com.novus.salat.global._

scala> import com.mongodb.casbah.Implicits._
import com.mongodb.casbah.Implicits._

scala> import hugh.model._
import hugh.model._

scala> val child = Child("C")
child: hugh.model.Child = Child(C)

scala> val parent = Parent("testId", child)    
parent: hugh.model.Parent = Parent(testId,Child(C))

scala> grater[Child].asDBObject(child)
res0: com.mongodb.casbah.Imports.DBObject = { "_typeHint" : "hugh.model.Child" , "value" : "C"}

scala> grater[Parent].asDBObject(parent)
res1: com.mongodb.casbah.Imports.DBObject = { "_typeHint" : "hugh.model.Parent" , "_id" : "testId" , "nested" : { "_typeHint" : "hugh.model.Child" , "value" : "C"}}

demo.scala

package hugh.demo

import com.mongodb.casbah._
import com.novus.salat.grater
import com.novus.salat.annotations._
import com.novus.salat.global._
import com.mongodb.casbah.Implicits._
import hugh.model._

// hey, check out SalatDAO at https://github.com/novus/salat/wiki/SalatDAO

object TestNesting {
  def main(args: Array[String]) {
    val db  = MongoConnection()("childtest")
    val coll = db("testColl")
    coll.drop

    val child = Child("C")
    val parent = Parent("testId", child)

    // A conversion straight back to Parent will work here as the DBObject has
    // the Child, not a DBObject of the child 
    println(grater[Parent].asDBObject(parent))

    // On save, the Child class gets flattened to a DBList because
    // it implements Product
    coll.save(grater[Parent].asDBObject(parent))

    coll.findOneByID("testId") map { result =>
      // This row will cause an error as it expects type "Child" and receives
      // A db list [ "C" ]
      println(grater[Parent].asObject(result))
    }
  }
} 

model.scala

package hugh.model

import com.mongodb.casbah._
import com.novus.salat.grater
import com.novus.salat.annotations._
import com.novus.salat.global._
import com.mongodb.casbah.Implicits._

case class Child(value: String)
case class Parent(@Key("_id") id: String, nested: Child)