Implementation of rfc7396

MergePatch.scala

import argonaut._, Argonaut._

object MergePatch {
  def mergePatch(json: Json, patch: Json): Json = {
    val target = json.objectOrEmpty.toMap
    if (patch.isObject) {
      patch.objectOrEmpty.toList.foldLeft(target) { case (map, (k, v)) =>
        if (map.isDefinedAt(k)) {
          if (v.isNull) map - k else map + (k -> mergePatch(map(k), v))
        } else {
          map + (k -> v)
        }
      }.asJson
    } else patch
  }
}