Update Scala to 3.8.1 (#249)

* Update Scala to 3.8.1

Also update the JVM version used to run tests to 25.

I was hoping we will be able to get rid of `-J--sun-misc-unsafe-memory-access=allow` but unfortunately nope, that piece of code is compiled by scalac and injected into dependency JARs... so we will have to wait for the next Scala LTS.

See: scala/scala3#24109 (comment)

Author: Ostrzyciel

.github/workflows/scala.yml

@@ -21,7 +21,7 @@ jobs:
           - os: ubuntu-latest
             java: 21
           - os: ubuntu-latest
-            java: 24
+            java: 25
     runs-on: ${{ matrix.os }}
 
     steps:

.scalafix.conf

@@ -5,3 +5,5 @@ rules = [
   RedundantSyntax
 ]
 ExplicitResultTypes.memberVisibility = [Public]
+# Needed for support of Scala versions not yet officially supported by Scalafix
+ExplicitResultTypes.fetchScala3CompilerArtifactsOnVersionMismatch = true

.scalafmt.conf

@@ -1,5 +1,5 @@
-version = 3.10.3
-runner.dialect = scala36
+version = 3.10.4
+runner.dialect = Scala3Future
 maxColumn = 100
 align.preset=none
 rewrite.trailingCommas.style = always

build.sbt

@@ -1,5 +1,5 @@
 ThisBuild / semanticdbEnabled := true
-lazy val scalaV = "3.7.4"
+lazy val scalaV = "3.8.1"
 ThisBuild / scalaVersion := scalaV
 
 resolvers +=
@@ -17,15 +17,18 @@ def isDevBuild: Boolean =
   sys.env.get("DEV_BUILD").exists(s => s != "0" && s != "false")
 
 lazy val graalOptions = Seq(
-  // If running on Scala <3.8 and JDK >=24, we need to allow unsafe memory access.
-  // Otherwise, we get annoying warnings on startup.
-  // https://github.com/scala/scala3/issues/9013
-  // Remove this after moving to Scala 3.8
-  if (scalaV.split('.')(1).toInt < 8) Seq("-J--sun-misc-unsafe-memory-access=allow") else Nil,
   // Do a fast build if it's a dev build
   // For the release build, optimize for speed and make a build report
   if (isDevBuild) Seq("-Ob") else Seq("-O3", "--emit build-report"),
 ).flatten ++ Seq(
+  // If using dependencies on Scala <3.8 and JDK >=24, we need to allow unsafe memory access.
+  // Otherwise, we get annoying warnings on startup.
+  // https://github.com/scala/scala3/issues/9013
+  // Remove this after dependency upgrades to Scala 3.8+
+  // See this thread for an explanation of why this requires also updates in dependencies:
+  // https://github.com/scala/scala3/pull/24109#issuecomment-3786629196
+  "-J--sun-misc-unsafe-memory-access=allow",
+  // Custom Graal features
   "--features=eu.neverblink.jelly.cli.graal.ProtobufFeature," +
     "eu.neverblink.jelly.cli.graal.JenaInternalsFeature," +
     "eu.neverblink.jelly.cli.graal.LargeXmlFeature",

src/main/scala/eu/neverblink/jelly/cli/command/Version.scala

@@ -36,6 +36,7 @@ object Version extends JellyCommand[VersionOptions]:
          |Jelly-JVM   $jellyV
          |Apache Jena $jenaV
          |JVM         ${System.getProperty("java.vm.name")} ${System.getProperty("java.vm.version")}
+         |Scala       ${BuildInfo.scalaVersion}
          |-------------------------------------------------------------
          |""".stripMargin.trim)
     // Print feature support info