address review comments

compiler/src/dotty/tools/MainGenericCompiler.scala

@@ -101,16 +101,14 @@ object MainGenericCompiler {
       process(tail, settings.withScalaArgs("-verbose"))
     case ("-q" | "-quiet") :: tail =>
       process(tail, settings.withQuiet)
-    case "-Oshort" :: tail =>
-      process(tail, settings.withJavaArgs("-XX:+TieredCompilation", "-XX:TieredStopAtLevel=1"))
     case "-repl" :: tail =>
       process(tail, settings.withCompileMode(CompileMode.Repl))
     case "-script" :: targetScript :: tail =>
       process(Nil, settings
         .withCompileMode(CompileMode.Script)
         .withJavaProps("script.path" -> targetScript)
         .withTargetScript(targetScript)
-        .withScriptArgs(tail.toList*))
+        .withScriptArgs(tail*))
     case "-compile" :: tail =>
       process(tail, settings.withCompileMode(CompileMode.Compile))
     case "-decompile" :: tail =>
@@ -126,23 +124,18 @@ object MainGenericCompiler {
     case "-with-compiler" :: tail =>
       process(tail, settings.withCompiler)
     case ("-cp" | "-classpath" | "--class-path") :: cp :: tail =>
-      val cpEntries = cp.split(classpathSeparator).toList
-      val singleEntryClasspath: Boolean = cpEntries.sizeIs == 1
-      val globdir: String = if singleEntryClasspath then cp.replaceAll("[\\\\/][^\\\\/]*$", "") else "" // slash/backslash agnostic
-      def validGlobbedJar(s: String): Boolean = s.startsWith(globdir) && ((s.toLowerCase.endsWith(".jar") || s.toLowerCase.endsWith(".zip")))
-      val (tailargs, newEntries) = if singleEntryClasspath && validGlobbedJar(cpEntries.head) then
-        // reassemble globbed wildcard classpath
-        // globdir is wildcard directory for globbed jar files, reconstruct the intended classpath
-        val cpJars = tail.takeWhile( f => validGlobbedJar(f) )
-        val remainingArgs = tail.drop(cpJars.size)
-        (remainingArgs, cpEntries ++ cpJars)
-      else
-        (tail, cpEntries)
-
+      val (tailargs, newEntries) = MainGenericRunner.processClasspath(cp, tail)
       process(tailargs, settings.copy(classPath = settings.classPath ++ newEntries.filter(_.nonEmpty)))
-    case (o @ javaOption(stripped)) :: tail =>
+    case "-Oshort" :: tail =>
+      // Nothing is to be done here. Request that the user adds the relevant flags manually.
+      // i.e this has no effect when MainGenericRunner is invoked programatically.
+      val addTC="-XX:+TieredCompilation"
+      val tStopAtLvl="-XX:TieredStopAtLevel=1"
+      println(s"ignoring deprecated -Oshort flag, please add `-J$addTC` and `-J$tStopAtLvl` flags manually")
+      process(tail, settings)
+    case javaOption(stripped) :: tail =>
       process(tail, settings.withJavaArgs(stripped))
-    case (javaPropOption(opt, value)) :: tail =>
+    case javaPropOption(opt, value) :: tail =>
       process(tail, settings.withJavaProps(opt -> value))
     case arg :: tail =>
       process(tail, settings.withResidualArgs(arg))

compiler/src/dotty/tools/MainGenericRunner.scala

@@ -100,6 +100,20 @@ object MainGenericRunner {
 
   val classpathSeparator = File.pathSeparator
 
+  def processClasspath(cp: String, tail: List[String]): (List[String], List[String]) =
+    val cpEntries = cp.split(classpathSeparator).toList
+    val singleEntryClasspath: Boolean = cpEntries.take(2).size == 1
+    val globdir: String = if singleEntryClasspath then cp.replaceAll("[\\\\/][^\\\\/]*$", "") else "" // slash/backslash agnostic
+    def validGlobbedJar(s: String): Boolean = s.startsWith(globdir) && ((s.toLowerCase.endsWith(".jar") || s.toLowerCase.endsWith(".zip")))
+    if singleEntryClasspath && validGlobbedJar(cpEntries.head) then
+      // reassemble globbed wildcard classpath
+      // globdir is wildcard directory for globbed jar files, reconstruct the intended classpath
+      val cpJars = tail.takeWhile( f => validGlobbedJar(f) )
+      val remainingArgs = tail.drop(cpJars.size)
+      (remainingArgs, cpEntries ++ cpJars)
+    else
+      (tail, cpEntries)
+
   @sharable val javaOption = raw"""-J(.*)""".r
   @sharable val scalaOption = raw"""@.*""".r
   @sharable val colorOption = raw"""-color:.*""".r
@@ -110,21 +124,8 @@ object MainGenericRunner {
     case "-run" :: fqName :: tail =>
       process(tail, settings.withExecuteMode(ExecuteMode.Run).withTargetToRun(fqName))
     case ("-cp" | "-classpath" | "--class-path") :: cp :: tail =>
-      val cpEntries = cp.split(classpathSeparator).toList
-      val singleEntryClasspath: Boolean = cpEntries.take(2).size == 1
-      val globdir: String = if singleEntryClasspath then cp.replaceAll("[\\\\/][^\\\\/]*$", "") else "" // slash/backslash agnostic
-      def validGlobbedJar(s: String): Boolean = s.startsWith(globdir) && ((s.toLowerCase.endsWith(".jar") || s.toLowerCase.endsWith(".zip")))
-      val (tailargs, newEntries) = if singleEntryClasspath && validGlobbedJar(cpEntries.head) then
-        // reassemble globbed wildcard classpath
-        // globdir is wildcard directory for globbed jar files, reconstruct the intended classpath
-        val cpJars = tail.takeWhile( f => validGlobbedJar(f) )
-        val remainingArgs = tail.drop(cpJars.size)
-        (remainingArgs, cpEntries ++ cpJars)
-      else
-        (tail, cpEntries)
-
+      val (tailargs, newEntries) = processClasspath(cp, tail)
       process(tailargs, settings.copy(classPath = settings.classPath ++ newEntries.filter(_.nonEmpty)))
-
     case ("-version" | "--version") :: _ =>
       settings.copy(
         executeMode = ExecuteMode.Repl,
@@ -170,7 +171,7 @@ object MainGenericRunner {
         val newSettings = if arg.startsWith("-") then settings else settings.withPossibleEntryPaths(arg).withModeShouldBePossibleRun
         process(tail, newSettings.withResidualArgs(arg))
   end process
-      
+
   def main(args: Array[String]): Unit =
     val scalaOpts = envOrNone("SCALA_OPTS").toArray.flatMap(_.split(" ")).filter(_.nonEmpty)
     val allArgs = scalaOpts ++ args

dist/bin/scala

@@ -33,9 +33,9 @@ while [[ $# -gt 0 ]]; do
     -D*)
       # pass to scala as well: otherwise we lose it sometimes when we
       # need it, e.g. communicating with a server compiler.
+      # respect user-supplied -Dscala.usejavacp
       addJava "$1"
       addScala "$1"
-      # respect user-supplied -Dscala.usejavacp
       shift
       ;;
     -J*)
@@ -47,7 +47,7 @@ while [[ $# -gt 0 ]]; do
       ;;
     -classpath*)
       if [ "$1" != "${1##* }" ]; then
-        # hashbang-combined args "-classpath 'lib/*'"
+        # -classpath and its value have been supplied in a single string e.g. "-classpath 'lib/*'"
         A=$1 ; shift # consume $1 before adding its substrings back
         set -- $A "$@" # split $1 on whitespace and put it back
       else

dist/bin/scalac

@@ -32,12 +32,24 @@ source "$PROG_HOME/bin/common"
 
 while [[ $# -gt 0 ]]; do
   case "$1" in
+    --)
+      # pass all remaining arguments to scala, e.g. to avoid interpreting them here as -D or -J
+      while [[ $# -gt 0 ]]; do addScala "$1" && shift ; done
+      ;;
+    -script)
+      # pass all remaining arguments to scala, e.g. to avoid interpreting them here as -D or -J
+      while [[ $# -gt 0 ]]; do addScala "$1" && shift ; done
+      ;;
+    # Optimize for short-running applications, see https://github.com/lampepfl/dotty/issues/222
+    -Oshort)
+      addScala "-Oshort" && \
+      addJava "-XX:+TieredCompilation" && addJava "-XX:TieredStopAtLevel=1" && shift ;;
     -D*)
       # pass to scala as well: otherwise we lose it sometimes when we
       # need it, e.g. communicating with a server compiler.
+      # respect user-supplied -Dscala.usejavacp
       addJava "$1"
       addScala "$1"
-      # respect user-supplied -Dscala.usejavacp
       shift
       ;;
     -J*)
@@ -49,7 +61,7 @@ while [[ $# -gt 0 ]]; do
       ;;
     -classpath*)
       if [ "$1" != "${1##* }" ]; then
-        # hashbang-combined args "-classpath 'lib/*'"
+        # -classpath and its value have been supplied in a single string e.g. "-classpath 'lib/*'"
         A=$1 ; shift # consume $1 before adding its substrings back
         set -- $A "$@" # split $1 on whitespace and put it back
       else