Merge pull request #2319 from bjaglin/38

build and test against scala 3.8.1

Author: bjaglin

.github/workflows/ci.yml

@@ -43,6 +43,7 @@ jobs:
       - uses: coursier/setup-action@v2
         with:
           apps: sbt
+          jvm: zulu:17 # for scala 3.8+
       - run: ./bin/scalafmt --test
       - run: sbt "dogfoodScalafixInterfaces; scalafixAll --check"
   mima:
@@ -55,4 +56,5 @@ jobs:
       - uses: coursier/setup-action@v2
         with:
           apps: sbt
+          jvm: zulu:17 # for scala 3.8+
       - run: sbt versionPolicyCheck

.github/workflows/release.yml

@@ -13,7 +13,7 @@ jobs:
       - uses: coursier/setup-action@v2
         with:
           apps: sbt
-          jvm: temurin:8
+          jvm: temurin:17 # needed for scala 3.8+ modules, all others are producing Java 8 bytecode 
       - uses: olafurpg/setup-gpg@v3
       - name: Check that major or minor was bumped upon compatibility breakage
         if: startsWith(github.ref, 'refs/tags/v')

.jvmopts

@@ -1,6 +1,6 @@
 -Xss2m
 -Xms2G
--Xmx4G
+-Xmx8G
 -XX:ReservedCodeCacheSize=512m
 -XX:+UseG1GC
 -XX:+TieredCompilation

AGENTS.md

@@ -2,7 +2,7 @@
 
 ## Project Overview
 
-Scalafix is a refactoring and linting tool for Scala. It enables syntactic and semantic source code transformations through a rule-based system. The project targets multiple Scala versions (2.12, 2.13, 3.3-3.7) and is built using a complex sbt-projectmatrix setup.
+Scalafix is a refactoring and linting tool for Scala. It enables syntactic and semantic source code transformations through a rule-based system. The project targets multiple Scala versions (2.12, 2.13, 3.3-3.8) and is built using a complex sbt-projectmatrix setup.
 
 **Core Architecture:**
 - `scalafix-interfaces`: Java API for JVM integration (cross-platform, no Scala dependency)

bin/test-release.sh

@@ -6,7 +6,7 @@ version=$1
 scala212=2.12.21
 scala213=2.13.18
 scala3LTS=3.3.7
-scala3Next=3.7.4
+scala3Next=3.8.1
 
 cs resolve \
   ch.epfl.scala:scalafix-interfaces:$version  \

build.sbt

@@ -36,6 +36,7 @@ lazy val interfaces = project
       props.put("scala35", scala35)
       props.put("scala36", scala36)
       props.put("scala37", scala37)
+      props.put("scala38", scala38)
       props.put("scala3LTS", scala3LTS)
       props.put("scala3Next", scala3Next)
       val out =
@@ -45,9 +46,12 @@ lazy val interfaces = project
       List(out)
     },
     (Compile / javacOptions) ++= List(
-      "-Xlint:all",
+      "-Xlint:all,-options",
       "-Werror"
-    ),
+    ) ++ {
+      if (System.getProperty("java.version").startsWith("1.8")) Nil
+      else List("--release", "8")
+    },
     (Compile / doc / javacOptions) := List("-Xdoclint:none"),
     (Compile / javaHome) := inferJavaHome(),
     (Compile / doc / javaHome) := inferJavaHome(),
@@ -142,6 +146,7 @@ lazy val reflect = projectMatrix
     moduleName := "scalafix-reflect",
     isFullCrossVersion,
     libraryDependencies ++= Seq(
+      coursierInterfaces,
       semanticdbScalacCore,
       "org.scala-lang" % "scala-compiler" % scalaVersion.value,
       "org.scala-lang" % "scala-reflect" % scalaVersion.value

project/Dependencies.scala

@@ -12,8 +12,9 @@ object Dependencies {
   val scala35 = "3.5.2"
   val scala36 = "3.6.4"
   val scala37 = "3.7.4"
+  val scala38 = "3.8.1"
   val scala3LTS = scala33
-  val scala3Next = sys.props.getOrElse("scala3.nightly", scala37)
+  val scala3Next = sys.props.getOrElse("scala3.nightly", scala38)
 
   val bijectionCoreV = "0.9.8"
   val collectionCompatV = "2.14.0"

project/Mima.scala

@@ -7,8 +7,9 @@ object Mima {
     // See https://github.com/lightbend/mima
     Seq(
       ProblemFilters.exclude[Problem]("scalafix.internal.*"),
-      ProblemFilters.exclude[Problem]("scala.meta.internal.*")
+      ProblemFilters.exclude[Problem]("scala.meta.internal.*"),
       // Exceptions
+      ProblemFilters.exclude[ReversedMissingMethodProblem]("scalafix.interfaces.Scalafix.scala38")
     )
   }
 }

project/ScalafixBuild.scala

@@ -34,13 +34,13 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
     // https://github.com/scalameta/scalameta/issues/2485
     lazy val coreScalaVersions = Seq(scala212, scala213)
     lazy val cliScalaVersions = {
-      val scala3Versions = Seq(scala33, scala35, scala36, scala37)
+      val scala3Versions = Seq(scala33, scala35, scala36, scala37, scala38)
       val jdk = System.getProperty("java.specification.version").toDouble
-      val unsupportedVersions =
-        if (jdk >= 25) Seq(scala212, scala35, scala36)
-        else Nil
-      (coreScalaVersions ++ scala3Versions :+ scala3Next)
-        .diff(unsupportedVersions)
+      val unsupportedVersions: Set[String] =
+        if (jdk >= 25) Set(scala212, scala35, scala36)
+        else if (jdk < 17) Set(scala38)
+        else Set.empty
+      (coreScalaVersions ++ scala3Versions).filterNot(unsupportedVersions)
     }
     lazy val cliScalaVersionsWithTargets: Seq[(String, TargetAxis)] =
       cliScalaVersions.map(sv => (sv, TargetAxis(sv))) ++
@@ -62,10 +62,12 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
           val xsource3 = TargetAxis(sv, xsource3 = true)
 
           (prevVersions :+ xsource3).map((sv, _))
-        } ++ Seq(
-          (scala3Next, TargetAxis(scala213)),
-          (scala3Next, TargetAxis(scala3LTS))
-        )
+        } ++ cliScalaVersions.intersect(Seq(scala3Next)).flatMap { sv =>
+          Seq(
+            (sv, TargetAxis(scala213)),
+            (sv, TargetAxis(scala3LTS))
+          )
+        }
 
     lazy val publishLocalTransitive =
       taskKey[Unit]("Run publishLocal on this project and its dependencies")
@@ -85,16 +87,21 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
       scalaVersion.value.startsWith("2.12")
     }
     lazy val warnUnused = Def.setting {
-      if (isScala3.value)
+      val minor = scalaVersion.value.split('.')(1).toInt
+      if (isScala3.value && minor >= 7)
+        Seq("-Wunused:all")
+      else if (isScala3.value)
         Seq(
           "-Wunused:all",
-          "-Wunused:unsafe-warn-patvars" // only needed for <3.7.0
+          "-Wunused:unsafe-warn-patvars"
         )
       else if (isScala213.value) Seq("-Wunused")
       else Seq("-Ywarn-unused")
     }
     lazy val targetJvm = Def.setting {
-      if (isScala3.value) Seq("-release:8")
+      val minor = scalaVersion.value.split('.')(1).toInt
+      if (isScala3.value && minor >= 8) Seq("-release:17")
+      else if (isScala3.value) Seq("-release:8")
       else if (isScala213.value) Seq("-release", "8")
       else Seq("-target:jvm-1.8")
     }
@@ -150,6 +157,7 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
         "scala35" -> scala35,
         "scala36" -> scala36,
         "scala37" -> scala37,
+        "scala38" -> scala38,
         "scala3LTS" -> scala3LTS,
         "scala3Next" -> scala3Next,
         sbtVersion
@@ -241,6 +249,7 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
   )
 
   private val PreviousScalaVersion: Map[String, Option[String]] = Map(
+    scala38 -> None
   )
 
   override def buildSettings: Seq[Setting[_]] = List(

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

@@ -42,6 +42,8 @@ final class ScalafixImpl extends Scalafix {
     Versions.scala36
   override def scala37(): String =
     Versions.scala37
+  override def scala38(): String =
+    Versions.scala38
   override def scala3LTS(): String =
     Versions.scala3LTS
   override def scala3Next(): String =