Trying to get fsc doing the right thing with re...

Trying to get fsc doing the right thing with respect to absolute and
relative paths. My knowledge of the problem had heretofore been second
hand, and my understanding of it incomplete. The real problem I have
determined is that there are a bunch of different things which go wrong
if relative paths start being resolved from a different base, each of
which needs custom handling.

  classpath-style options, e.g. fsc -cp ../foo.jar
  path-style options, e.g. fsc -d ../mydir
  file arguments, e.g. fsc ../foo.scala

So it was more work than I had realized, or I probably wouldn't have
even touched it. But now it seems to be working as one would want. I
also poured some readability onto the fsc help output.

Closes #4395, no review, but community input would be great.

1 files changed, 27 insertions, 10 deletions

diff --git a/src/compiler/scala/tools/nsc/settings/FscSettings.scala b/src/compiler/scala/tools/nsc/settings/FscSettings.scala
index a219148b16..bb62750026 100644
--- a/src/compiler/scala/tools/nsc/settings/FscSettings.scala
+++ b/src/compiler/scala/tools/nsc/settings/FscSettings.scala
@@ -8,28 +8,45 @@ package nsc
 package settings
 
 import util.ClassPath
+import io.{ Directory, Path, AbstractFile }
 
 class FscSettings(error: String => Unit) extends Settings(error) {
   outer =>
 
-  def this() = this(Console.println)
+  locally {
+    disable(prompt)
+    disable(resident)
+  }
 
+  val currentDir   = StringSetting ("-current-dir", "path", "Base directory for resolving relative paths", "").internalOnly()
   val reset        = BooleanSetting("-reset",    "Reset compile server caches")
   val shutdown     = BooleanSetting("-shutdown", "Shutdown compile server")
   val server       = StringSetting ("-server",   "hostname:portnumber", "Specify compile server socket", "")
-  val preferIPv4   = BooleanSetting("-ipv4", "Use IPv4 rather than IPv6 for the server socket")
-  val absClasspath = BooleanSetting("-absolute-cp", "Make classpath elements absolute paths before sending to server") .
-      withPostSetHook (_ => absolutizeClasspath())
+  val preferIPv4   = BooleanSetting("-ipv4",     "Use IPv4 rather than IPv6 for the server socket")
   val idleMins     = IntSetting    ("-max-idle", "Set idle timeout in minutes for fsc (use 0 for no timeout)",
                                               30, Some(0, Int.MaxValue), (_: String) => None)
 
-  disable(prompt)
-  disable(resident)
+  // For improved help output, separating fsc options from the others.
+  def fscSpecific = Set[Settings#Setting](
+    currentDir, reset, shutdown, server, preferIPv4, idleMins
+  )
+  val isFscSpecific: String => Boolean = fscSpecific map (_.name)
+
+  /** If a setting (other than a PathSetting) represents a path or paths.
+   *  For use in absolutization.
+   */
+  private def holdsPath = Set[Settings#Setting](
+    d, dependencyfile, pluginsDir, Ygenjavap
+  )
 
-  // Make the classpath absolute: for going from client to server.
-  private def absolutizeClasspath() {
-    userSetSettings collect {
-      case x: PathSetting => x.value = ClassPath.makeAbsolute(x.value)
+  /** All user set settings rewritten with absolute paths. */
+  def absolutize(root: Path) {
+    def rewrite(p: String) = (root resolve Path(p)).normalize.path
+    userSetSettings foreach {
+      case p: OutputSetting => p.outputDirs setSingleOutput AbstractFile.getDirectory(rewrite(p.value))
+      case p: PathSetting   => p.value = ClassPath.map(p.value, rewrite)
+      case p: StringSetting => if (holdsPath(p)) p.value = rewrite(p.value)
+      case _                => ()
     }
   }
 }