Cross build to sbt 2.x

build.sbt

@@ -3,9 +3,12 @@ organization := "com.github.sbt"
 homepage := Some(url("https://github.com/sbt/sbt-native-packager"))
 
 Global / onChangedBuildSource := ReloadOnSourceChanges
-Global / scalaVersion := "2.12.20"
 
 // crossBuildingSettings
+lazy val scala212 = "2.12.20"
+lazy val scala3 = "3.3.4"
+Global / scalaVersion := scala3
+crossScalaVersions := Seq(scala3, scala212)
 (pluginCrossBuild / sbtVersion) := {
   scalaBinaryVersion.value match {
     case "2.12" => "1.1.6"
@@ -48,8 +51,7 @@ libraryDependencies ++= {
 // scala version depended libraries
 libraryDependencies ++= {
   scalaBinaryVersion.value match {
-    case "2.10" => Nil
-    case _ =>
+    case "2.12" =>
       Seq(
         // Do NOT upgrade these dependencies to 2.x or newer! sbt-native-packager is a sbt-plugin
         // and gets published with Scala 2.12, therefore we need to stay at the same major version
@@ -58,6 +60,8 @@ libraryDependencies ++= {
         "org.scala-lang.modules" %% "scala-parser-combinators" % "1.1.2", // Do not upgrade beyond 1.x
         "org.scala-lang.modules" %% "scala-xml" % "2.2.0"
       )
+    case _ =>
+      Nil
   }
 }
 

src/main/scala-2.12/com/typesafe/sbt/packager/PluginCompat.scala

@@ -0,0 +1,26 @@
+package com.typesafe.sbt.packager
+
+import java.nio.file.{Path => NioPath}
+import java.util.jar.Attributes
+import sbt.*
+import xsbti.{FileConverter, HashedVirtualFileRef, VirtualFile}
+
+private[packager] object PluginCompat {
+  type FileRef = java.io.File
+  type ArtifactPath = java.io.File
+  type Out = java.io.File
+
+  def toNioPath(a: Attributed[File])(implicit conv: FileConverter): NioPath =
+    a.data.toPath()
+  def toFile(a: Attributed[File])(implicit conv: FileConverter): File =
+    a.data
+  def artifactPathToFile(ref: File)(implicit conv: FileConverter): File =
+    ref
+  def toNioPaths(cp: Seq[Attributed[File]])(implicit conv: FileConverter): Vector[NioPath] =
+    cp.map(_.data.toPath()).toVector
+  def toFiles(cp: Seq[Attributed[File]])(implicit conv: FileConverter): Vector[File] =
+    cp.map(_.data).toVector
+
+  def classpathAttr = Attributes.Name.CLASS_PATH
+  def mainclassAttr = Attributes.Name.MAIN_CLASS
+}

src/main/scala-3/com/typesafe/sbt/packager/Compat.scala

@@ -0,0 +1,3 @@
+package com.typesafe.sbt.packager
+
+object Compat {}

src/main/scala-3/com/typesafe/sbt/packager/PluginCompat.scala

@@ -0,0 +1,56 @@
+package com.typesafe.sbt.packager
+
+import java.io.File
+import java.nio.file.{ Path => NioPath }
+import java.util.jar.Attributes
+import sbt.*
+import xsbti.{ FileConverter, HashedVirtualFileRef, VirtualFile, VirtualFileRef }
+import sbt.internal.RemoteCache
+
+private[packager] object PluginCompat:
+  type FileRef = HashedVirtualFileRef
+  type ArtifactPath = VirtualFileRef
+  type Out = VirtualFile
+  type IncludeArtifact = Any => Boolean
+
+  val artifactStr = Keys.artifactStr
+  val moduleIDStr = Keys.moduleIDStr
+  def parseModuleIDStrAttribute(str: String): ModuleID =
+    Classpaths.moduleIdJsonKeyFormat.read(str)
+  def moduleIDToStr(m: ModuleID): String =
+    Classpaths.moduleIdJsonKeyFormat.write(m)
+
+  def parseArtifactStrAttribute(str: String): Artifact =
+    import sbt.librarymanagement.LibraryManagementCodec.ArtifactFormat
+    import sjsonnew.support.scalajson.unsafe.* 
+    Converter.fromJsonUnsafe[Artifact](Parser.parseUnsafe(str))
+  def artifactToStr(art: Artifact): String =
+    import sbt.librarymanagement.LibraryManagementCodec.ArtifactFormat
+    import sjsonnew.support.scalajson.unsafe.*
+    CompactPrinter(Converter.toJsonUnsafe(art))
+
+  def toNioPath(a: Attributed[HashedVirtualFileRef])(using conv: FileConverter): NioPath =
+    conv.toPath(a.data)
+  def toNioPath(ref: HashedVirtualFileRef)(using conv: FileConverter): NioPath =
+    conv.toPath(ref)
+  inline def toFile(a: Attributed[HashedVirtualFileRef])(using conv: FileConverter): File =
+    toNioPath(a).toFile()
+  inline def toFile(ref: HashedVirtualFileRef)(using conv: FileConverter): File =
+    toNioPath(ref).toFile()
+  def artifactPathToFile(ref: VirtualFileRef)(using conv: FileConverter): File =
+    conv.toPath(ref).toFile()
+  def toArtifactPath(f: File)(using conv: FileConverter): ArtifactPath =
+    conv.toVirtualFile(f.toPath())
+  def toNioPaths(cp: Seq[Attributed[HashedVirtualFileRef]])(using conv: FileConverter): Vector[NioPath] =
+    cp.map(toNioPath).toVector
+  inline def toFiles(cp: Seq[Attributed[HashedVirtualFileRef]])(using conv: FileConverter): Vector[File] =
+    toNioPaths(cp).map(_.toFile())
+  def toFileRef(x: File)(using conv: FileConverter): FileRef =
+    conv.toVirtualFile(x.toPath())
+  def getName(ref: FileRef): String =
+    ref.name()
+  def getArtifactPathName(ref: ArtifactPath): String =
+    ref.name()
+  def classpathAttr: String = Attributes.Name.CLASS_PATH.toString()
+  def mainclassAttr: String = Attributes.Name.MAIN_CLASS.toString()
+end PluginCompat