Drop Scala 2 for tasty-lib module

Author: Gedochao

build.mill.scala

@@ -107,7 +107,8 @@ object `build-module` extends Cross[Build](Scala.scala3MainVersions)
     with CrossScalaDefaultToInternal
 object runner        extends Runner
 object `test-runner` extends TestRunner
-object `tasty-lib`   extends Cross[TastyLib](Scala.all) with CrossScalaDefaultToInternal
+object `tasty-lib`   extends Cross[TastyLib](Scala.scala3MainVersions)
+    with CrossScalaDefaultToInternal
 // Runtime classes used within native image on Scala 3 replacing runtime from Scala
 object `scala3-runtime` extends Cross[Scala3Runtime](Scala.scala3MainVersions)
     with CrossScalaDefaultToInternal
@@ -1316,7 +1317,7 @@ trait TestRunner extends SbtModule
 
 trait TastyLib extends ScalaCliCrossSbtModule
     with ScalaCliPublishModule
-    with ScalaCliScalafixLegacyModule {
+    with ScalaCliScalafixModule {
   override def crossScalaVersion: String = crossValue
   def constantsFile: T[PathRef]          = Task(persistent = true) {
     val dir  = Task.dest / "constants"

modules/tasty-lib/src/main/scala/scala/build/tastylib/TastyBuffer.scala

@@ -59,7 +59,7 @@ class TastyBuffer(initialSize: Int) {
   /** Like writeNat, but for longs. Note that the binary representation of LongNat is identical to
     * Nat if the long value is in the range Int.MIN_VALUE to Int.MAX_VALUE.
     */
-  def writeLongNat(x: Long): Unit = {
+  private def writeLongNat(x: Long): Unit = {
     def writePrefix(x: Long): Unit = {
       val y = x >>> 7
       if (y != 0L) writePrefix(y)
@@ -79,7 +79,7 @@ class TastyBuffer(initialSize: Int) {
   def getNat(at: Addr): Int = getLongNat(at).toInt
 
   /** The long natural number at address `at` */
-  def getLongNat(at: Addr): Long = {
+  private def getLongNat(at: Addr): Long = {
     var b   = 0L
     var x   = 0L
     var idx = at.index

modules/tasty-lib/src/main/scala/scala/build/tastylib/TastyReader.scala

@@ -16,14 +16,14 @@ package scala.build.tastylib
 
 import java.io.OutputStream
 
-import scala.build.tastylib.TastyBuffer._
+import scala.build.tastylib.TastyBuffer.*
 import scala.collection.mutable
 
 class TastyReader(val bytes: Array[Byte], val start: Int, val end: Int, val base: Int = 0) {
 
   def this(bytes: Array[Byte]) = this(bytes, 0, bytes.length)
 
-  private[this] var bp: Int = start
+  private var bp: Int = start
 
   def pos: Int                  = bp
   def read: TastyReader.Bytes   = TastyReader.Bytes(bytes, start, bp)
@@ -50,7 +50,7 @@ class TastyReader(val bytes: Array[Byte], val start: Int, val end: Int, val base
   def readNat(): Int = readLongNat().toInt
   def readInt(): Int = readLongInt().toInt
 
-  def readLongNat(): Long = {
+  private def readLongNat(): Long = {
     var b = 0L
     var x = 0L
     while ({
@@ -62,7 +62,7 @@ class TastyReader(val bytes: Array[Byte], val start: Int, val end: Int, val base
     x
   }
 
-  def readLongInt(): Long = {
+  private def readLongInt(): Long = {
     var b       = bytes(bp)
     var x: Long = (b << 1).toByte >> 1
     bp += 1
@@ -95,6 +95,7 @@ class TastyReader(val bytes: Array[Byte], val start: Int, val end: Int, val base
   }
 
   def doUntil(end: Addr)(op: => Unit): Unit = {
+    // noinspection LoopVariableNotUpdated
     while (bp < index(end)) op
     assert(bp == index(end))
   }

modules/tasty-lib/src/main/scala/scala/build/tastylib/TastyUnpickler.scala

@@ -16,14 +16,14 @@ package scala.build.tastylib
 
 import scala.build.tastylib.TastyBuffer.NameRef
 import scala.build.tastylib.TastyFormat.NameTags
-import scala.build.tastylib.TastyName._
+import scala.build.tastylib.TastyName.*
 import scala.build.tastylib.TastyReader.Bytes
 import scala.collection.mutable
 
 object TastyUnpickler {
 
   final class NameTable {
-    private[this] val names = new mutable.ArrayBuffer[(Option[TastyName], Bytes)]
+    private val names = new mutable.ArrayBuffer[(Option[TastyName], Bytes)]
     def add(
       name: Option[TastyName],
       bytes: Bytes
@@ -39,7 +39,7 @@ import TastyUnpickler._
 
 private class TastyUnpickler(reader: TastyReader) { self =>
 
-  private[this] val nameTable = new NameTable
+  private val nameTable = new NameTable
 
   def nameAtRef: NameTable = nameTable