OpenRTB - Unextended Sealed traits - Linter Errors when using "oneof"

[ArulselvanMadhavan]

Hello,
Thanks for creating scalaPB. I find it to be very useful. I am trying to use scalaPB on openrtb - https://github.com/google/openrtb/blob/master/openrtb-core/src/main/protobuf/openrtb.proto

The scala classes created by scalaPB fail to compile on all occurences of "oneof" with an error saying "unextended sealed trait".

Error

[error] /Users/arul.madhavan/dev/adserver/adserver-shiba/target/scala-2.11/src_managed/main/com/google/openrtb/openrtb/BidRequest.scala:512:16: [UnextendedSealedTrait] This sealed trait is never extended
[error]   sealed trait DistributionchannelOneof extends _root_.scalapb.GeneratedOneof {
[error]                ^
[error] /Users/arul.madhavan/dev/adserver/adserver-shiba/target/scala-2.11/src_managed/main/com/google/openrtb/openrtb/BidRequest.scala:3859:20: [UnextendedSealedTrait] This sealed trait is never extended
[error]       sealed trait RequestOneof extends _root_.scalapb.GeneratedOneof {
[error]                    ^
[error] /Users/arul.madhavan/dev/adserver/adserver-shiba/target/scala-2.11/src_managed/main/com/google/openrtb/openrtb/BidResponse.scala:995:20: [UnextendedSealedTrait] This sealed trait is never extended
[error]       sealed trait AdmOneof extends _root_.scalapb.GeneratedOneof {
[error]                    ^
[error] /Users/arul.madhavan/dev/adserver/adserver-shiba/target/scala-2.11/src_managed/main/com/google/openrtb/openrtb/NativeRequest.scala:565:18: [UnextendedSealedTrait] This sealed trait is never extended
[error]     sealed trait AssetOneof extends _root_.scalapb.GeneratedOneof {
[error]                  ^
[error] /Users/arul.madhavan/dev/adserver/adserver-shiba/target/scala-2.11/src_managed/main/com/google/openrtb/openrtb/NativeResponse.scala:668:18: [UnextendedSealedTrait] This sealed trait is never extended
[error]     sealed trait AssetOneof extends _root_.scalapb.GeneratedOneof {
[error]                  ^
[error] 5 errors found
[error] (Compile / compileIncremental) Compilation failed

Sample Generated Code that is failing to compile

  sealed trait DistributionchannelOneof extends _root_.scalapb.GeneratedOneof {
    def isEmpty: _root_.scala.Boolean = false
    def isDefined: _root_.scala.Boolean = true
    def isSite: _root_.scala.Boolean = false
    def isApp: _root_.scala.Boolean = false
    def site: scala.Option[com.google.openrtb.openrtb.BidRequest.Site] = None
    def app: scala.Option[com.google.openrtb.openrtb.BidRequest.App] = None
  }
  object DistributionchannelOneof extends {
    @SerialVersionUID(0L)
    case object Empty extends com.google.openrtb.openrtb.BidRequest.DistributionchannelOneof {
      type ValueType = _root_.scala.Nothing
      override def isEmpty: _root_.scala.Boolean = true
      override def isDefined: _root_.scala.Boolean = false
      override def number: _root_.scala.Int = 0
      override def value: _root_.scala.Nothing = throw new java.util.NoSuchElementException("Empty.value")
    }
  
    @SerialVersionUID(0L)
    final case class Site(value: com.google.openrtb.openrtb.BidRequest.Site) extends com.google.openrtb.openrtb.BidRequest.DistributionchannelOneof {
      type ValueType = com.google.openrtb.openrtb.BidRequest.Site
      override def isSite: _root_.scala.Boolean = true
      override def site: scala.Option[com.google.openrtb.openrtb.BidRequest.Site] = Some(value)
      override def number: _root_.scala.Int = 3
    }
    @SerialVersionUID(0L)
    final case class App(value: com.google.openrtb.openrtb.BidRequest.App) extends com.google.openrtb.openrtb.BidRequest.DistributionchannelOneof {
      type ValueType = com.google.openrtb.openrtb.BidRequest.App
      override def isApp: _root_.scala.Boolean = true
      override def app: scala.Option[com.google.openrtb.openrtb.BidRequest.App] = Some(value)
      override def number: _root_.scala.Int = 4
    }
  }

Scala Version: 2.11.12
Linter Used: https://github.com/HairyFotr/linter
Protoc Version: 3.5.1
sbt-protoc: 0.99.18
ScalaPB Version: 0.7.1

  .settings(
    PB.targets in Compile := List(
      scalapb.gen(grpc = false, flatPackage = false) -> (sourceManaged in Compile).value
    ),
    includeFilter in PB.generate := new SimpleFileFilter(
      (f: File) => f.getName.equals("openrtb.proto")
    )
  )

[thesamet]

Hi @ArulselvanMadhavan , you are observing a bug in the linter that is unrelated to ScalaPB. I filed HairyFotr/linter#62

In the mean time, you can disable this specific lint check.