build and test against scala 3.9.0 (new LTS) (#2498)

- Keep a Scala 3 Next reference for backward compat, matching Scala 3 LTS
  until 3.10.0 is out.
- Keep building (unpublished/unused) core3 & reflect3 with Scala 3.3 for
  now, as it's unclear if/when we will need to use the latest LTS.

Author: bjaglin

bin/test-release.sh

@@ -5,8 +5,8 @@ version=$1
 
 scala212=2.12.21
 scala213=2.13.18
-scala3LTS=3.3.8
-scala3Next=3.8.4
+scala3LTS=3.9.0
+scala3Next=3.9.0
 
 cs resolve \
   ch.epfl.scala:scalafix-interfaces:$version  \

build.sbt

@@ -38,6 +38,7 @@ lazy val interfaces = project
       props.put("scala36", scala36)
       props.put("scala37", scala37)
       props.put("scala38", scala38)
+      props.put("scala39", scala39)
       props.put("scala3LTS", scala3LTS)
       props.put("scala3Next", scala3Next)
       val out =
@@ -99,7 +100,7 @@ lazy val core3 = project
   .settings(
     noPublishAndNoMima,
     buildInfoSettingsForCore,
-    scalaVersion := scala3LTS,
+    scalaVersion := scala33,
     libraryDependencies ++= Seq(
       googleDiff,
       metaconfig
@@ -163,7 +164,7 @@ lazy val reflect3 = project
   .settings(
     isFullCrossVersion,
     noPublishAndNoMima,
-    scalaVersion := scala3LTS,
+    scalaVersion := scala33,
     libraryDependencies ++= Seq(
       // CrossVersion.for3Use2_13 would only lookup a binary version artifact, but this is published with full version
       semanticdbScalacCore

docs/users/installation.md

@@ -9,7 +9,7 @@ Scalafix is tested to work with:
 
 * **macOS, Linux or Windows**
 * **Java LTS (8, 11, 17, 21 or 25)**
-* **Scala @SCALA212@, @SCALA213@, @SCALA3LTS@ LTS or @SCALA3NEXT@**
+* **Scala @SCALA212@, @SCALA213@, @SCALA3LTS@ LTS**
 
 Note that other setups may work, but could result in unexpected behavior.
 
@@ -84,7 +84,7 @@ in 2.13.x or 3.x). To fix both problems, add the following settings to `build.sb
   */
  inThisBuild(
    List(
-     scalaVersion := "@SCALA212@", // @SCALA213@, @SCALA3LTS@ or @SCALA3NEXT@
+     scalaVersion := "@SCALA212@", // @SCALA213@, @SCALA3LTS@
 +    semanticdbEnabled := true, // enable SemanticDB
 +    semanticdbVersion := scalafixSemanticdb.revision // only required for Scala 2.x
    )
@@ -107,7 +107,7 @@ in 2.13.x or 3.x). To fix both problems, add the following settings to `build.sb
   * https://www.scala-sbt.org/1.x/docs/sbt-1.3-Release-Notes.html#SemanticDB+support
   */
  lazy val myproject = project.settings(
-   scalaVersion := "@SCALA212@", // @SCALA213@, @SCALA3LTS@ or @SCALA3NEXT@
+   scalaVersion := "@SCALA212@", // @SCALA213@, @SCALA3LTS@
 +  semanticdbEnabled := true, // enable SemanticDB
 +  semanticdbVersion := scalafixSemanticdb.revision, // only required for Scala 2.x
 +  scalacOptions += {

project/Dependencies.scala

@@ -13,11 +13,12 @@ object Dependencies {
   val scala36 = "3.6.4"
   val scala37 = "3.7.4"
   val scala38 = "3.8.4"
-  val scala3LTS = scala33
-  val scala3Next = sys.props.getOrElse("scala3.nightly", scala38)
+  val scala39 = "3.9.0"
+  val scala3LTS = scala39
+  val scala3Next = sys.props.getOrElse("scala3.nightly", scala39)
 
   val scala2Versions = Seq(scala212, scala213)
-  val scala3Versions = Seq(scala33, scala35, scala36, scala37, scala38)
+  val scala3Versions = Seq(scala33, scala35, scala36, scala37, scala38, scala39)
 
   val bijectionCoreV = "0.9.8"
   val collectionCompatV = "2.14.0"

project/Mima.scala

@@ -8,6 +8,7 @@ object Mima {
     Seq(
       ProblemFilters.exclude[Problem]("scalafix.internal.*"),
       ProblemFilters.exclude[Problem]("scala.meta.internal.*"),
+      ProblemFilters.exclude[ReversedMissingMethodProblem]("scalafix.interfaces.Scalafix.scala39"),
       // private[scalafix], so not callable by clients, but package-private in Scala compiles to a public method that MiMa still sees.
       // Its symbol table parameter moved from scala.meta.internal.symtab.SymbolTable to scalafix.internal.symtab.SymbolTable; both are internal types.
       ProblemFilters.exclude[IncompatibleMethTypeProblem]("scalafix.testkit.RuleTest.fromPath")

project/ScalafixBuild.scala

@@ -34,7 +34,8 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
     lazy val cliScalaVersions = {
       val unsupportedVersions: Set[String] =
         if (Properties.isJavaAtLeast("25")) Set(scala212, scala35, scala36)
-        else if (!Properties.isJavaAtLeast("17")) Set(scala38)
+        else if (!Properties.isJavaAtLeast("17"))
+          Set(scala38, scala39, scala3Next)
         else Set.empty
       (coreScalaVersions ++ scala3Versions).filterNot(unsupportedVersions)
     }
@@ -147,6 +148,7 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
         "scala36" -> scala36,
         "scala37" -> scala37,
         "scala38" -> scala38,
+        "scala39" -> scala39,
         "scala3LTS" -> scala3LTS,
         "scala3Next" -> scala3Next,
         sbtVersion
@@ -239,6 +241,7 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
   )
 
   private val PreviousScalaVersion: Map[String, Option[String]] = Map(
+    "3.9.0" -> None
   )
 
   override def buildSettings: Seq[Setting[_]] = List(
@@ -305,7 +308,7 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
     Compile / unmanagedSourceDirectories ++= {
       val dir = (Compile / sourceDirectory).value
       scalaVersion.value match {
-        case `scala3LTS` => Seq(dir / "scala-3lts")
+        case `scala33` => Seq(dir / "scala-3.3")
         case `scala3Next` => Seq(dir / "scala-3next")
         case _ => Nil
       }

scalafix-cli/src/main/scala/scalafix/internal/interfaces/ScalafixImpl.scala

@@ -44,6 +44,8 @@ final class ScalafixImpl extends Scalafix {
     Versions.scala37
   override def scala38(): String =
     Versions.scala38
+  override def scala39(): String =
+    Versions.scala39
   override def scala3LTS(): String =
     Versions.scala3LTS
   override def scala3Next(): String =

scalafix-interfaces/src/main/java/scalafix/interfaces/Scalafix.java

@@ -95,6 +95,11 @@ public interface Scalafix {
      */
     String scala38();
 
+    /**
+     * The Scala 3.9 version in {@link #supportedScalaVersions()}
+     */
+    String scala39();
+
     /**
      * The Scala 3 LTS version in {@link #supportedScalaVersions()}
      */
@@ -169,6 +174,8 @@ static Scalafix fetchAndClassloadInstance(String requestedScalaVersion, List<Rep
             scalaVersionKey = "scala37";
         } else if (requestedScalaMajorMinorOrMajorVersion.equals("3.8")) {
             scalaVersionKey = "scala38";
+        } else if (requestedScalaMajorMinorOrMajorVersion.equals("3.9")) {
+            scalaVersionKey = "scala39";
         } else if (requestedScalaMajorMinorOrMajorVersion.startsWith("3")) {
             scalaVersionKey = "scala3Next";
         } else {