Remove -Xmax-classfile-name; hard-code to 240, like Scala 2.13.0-RC1 (#5872)

#5812 is still open since the limit is not respected in the backend.

Author: IDoCodingStuffs

compiler/src/dotty/tools/dotc/config/ScalaSettings.scala

@@ -64,7 +64,6 @@ class ScalaSettings extends Settings.SettingGroup {
   val Xhelp: Setting[Boolean] = BooleanSetting("-X", "Print a synopsis of advanced options.")
   val XnoForwarders: Setting[Boolean] = BooleanSetting("-Xno-forwarders", "Do not generate static forwarders in mirror classes.")
   val XmaxInlines: Setting[Int] = IntSetting("-Xmax-inlines", "Maximal number of successive inlines", 32)
-  val XmaxClassfileName: Setting[Int] = IntSetting("-Xmax-classfile-name", "Maximum filename length for generated classes", 255, 72 to 255)
   val Xmigration: Setting[ScalaVersion] = VersionSetting("-Xmigration", "Warn about constructs whose behavior may have changed since version.")
   val Xprint: Setting[List[String]] = PhasesSetting("-Xprint", "Print out program after")
   val XprintTypes: Setting[Boolean] = BooleanSetting("-Xprint-types", "Print tree types (debugging option).")

compiler/src/dotty/tools/dotc/core/NameOps.scala

@@ -13,6 +13,8 @@ object NameOps {
   object compactify {
     lazy val md5: MessageDigest = MessageDigest.getInstance("MD5")
 
+    final val CLASSFILE_NAME_CHAR_LIMIT = 240
+
     /** COMPACTIFY
      *
      *  The hashed name has the form (prefix + marker + md5 + marker + suffix), where
@@ -25,10 +27,11 @@ object NameOps {
      *
      *  (+6 for ".class"). MaxNameLength can therefore be computed as follows:
      */
-    def apply(s: String)(implicit ctx: Context): String = {
+    def apply(s: String): String = {
       val marker = "$$$$"
-      val limit: Int = ctx.settings.XmaxClassfileName.value
-      val MaxNameLength = (limit - 6) min 2 * (limit - 6 - 2 * marker.length - 32)
+
+      val MaxNameLength = (CLASSFILE_NAME_CHAR_LIMIT - 6) min
+        2 * (CLASSFILE_NAME_CHAR_LIMIT - 6 - 2 * marker.length - 32)
 
       def toMD5(s: String, edge: Int): String = {
         val prefix = s take edge

sbt-dotty/sbt-test/source-dependencies/compactify/build.sbt

@@ -3,8 +3,3 @@ TaskKey[Unit]("output-empty") := {
   val classes = (outputDirectory ** "*.class").get
   if (classes.nonEmpty) sys.error("Classes existed:\n\t" + classes.mkString("\n\t")) else ()
 }
-
-// apparently Travis CI stopped allowing long file names
-// it fails with the default setting of 255 characters so
-// we have to set lower limit ourselves
-scalacOptions ++= Seq("-Xmax-classfile-name", "240")

tests/pending/run/t8199.scala

@@ -39,7 +39,7 @@ object Test extends dotty.runtime.LegacyApp {
     checkClassName(c.getName)
   }
   def checkClassName(name: String): Unit = {
-    val defaultMaxClassFileLength = 255
+    val defaultMaxClassFileLength = 240
     assert((name + ".class").length <= defaultMaxClassFileLength, name)
   }
   def checkCallerImplClassName(): Unit = {