Modified JsonSpec

JsonSpec.scala

package play.api.json

import org.specs2.mutable._
import play.api.json._

object JsonSpec extends Specification {

  case class User(id: Long, name: String, friends: List[User], skills: Map[String, Int])

  implicit object UserFormat extends Format[User] {
    def reads(json: JsValue): User = User(
      (json \ "id").as[Long],
      (json \ "name").as[String],
      (json \ "friends").asOpt[List[User]].getOrElse(List()),
      (json \ "skills").asOpt[Map[String, Int]])

    def writes(u: User): JsValue = JsObject(
      Map(
        "id" -> JsNumber(u.id),
        "name" -> JsString(u.name),
        "friends" -> JsArray(u.friends.map(fr => JsObject(Map("id" -> JsNumber(fr.id), "name" -> JsString(fr.name))))),
        "skills" -> JsArray(u.skills.map { case (k, v) => JsObject(Map(k -> JsNumber(v))) }.toList)))
  }

  "JSON" should {

    "serialize and deserialize" in {
      val luigi = User(1, "Luigi", List(), Map())
      val kinopio = User(2, "Kinopio", List(), Map())
      val yoshi = User(3, "Yoshi", List(), Map())
      val mario = User(0, "Mario", List(luigi, kinopio, yoshi), Map("scala" -> 10))
      val jsonMario = toJson(mario)

      jsonMario.as[User] must equalTo(mario)
      (jsonMario \\ "name") must equalTo(Seq(JsString("Mario"), JsString("Luigi"), JsString("Kinopio"), JsString("Yoshi")))
      (jsonMario \\ "skills") must equalTo(Map("scala" -> JsNumber(10)))
    }

  }
}