Fix #2186: Synchronize classpath handling with Scala 2.12

This commit is a very crude port of the classpath handling as it exists
in the 2.12.x branch of scalac (hash: 232d95a198c94da0c6c8393624e83e9b9ac84e81),
this replaces the existing Classpath code that was adapted from scalac
years ago.

This code was written by Grzegorz Kossakowski, Michał Pociecha, Lukas
Rytz, Jason Zaugg and other scalac contributors, many thanks to them!

For more information on this implementation, see the description of the
PR that originally added it to scalac: https://github.com/scala/scala/pull/4060

Changes made to the copied code to get it to compile with dotty:
- Rename scala.tools.nsc.util.ClassPath to dotty.tools.io.ClassPath
- Rename scala.tools.nsc.classpath.* to dotty.tools.dotc.classpath.*
- Replace "private[nsc]" by "private[dotty]"
- Changed `isClass` methods in FileUtils to skip Scala 2.11
  implementation classes (needed until we stop being retro-compatible with
  Scala 2.11)

I also copied PlainFile.scala from scalac to get access to
`PlainNioFile`.

1 files changed, 13 insertions, 8 deletions

diff --git a/compiler/src/dotty/tools/dotc/config/PathResolver.scala b/compiler/src/dotty/tools/dotc/config/PathResolver.scala
index 159989e6f..f0709f4d3 100644
--- a/compiler/src/dotty/tools/dotc/config/PathResolver.scala
+++ b/compiler/src/dotty/tools/dotc/config/PathResolver.scala
@@ -4,8 +4,9 @@ package config
 
 import java.net.{ URL, MalformedURLException }
 import WrappedProperties.AccessControl
-import io.{ ClassPath, JavaClassPath, File, Directory, Path, AbstractFile }
-import ClassPath.{ JavaContext, DefaultJavaContext, join, split }
+import io.{ ClassPath, File, Directory, Path, AbstractFile }
+import classpath.{AggregateClassPath, ClassPathFactory }
+import ClassPath.{ JavaContext, join, split }
 import PartialFunction.condOpt
 import scala.language.postfixOps
 import core.Contexts._
@@ -128,7 +129,7 @@ object PathResolver {
       )
   }
 
-  def fromPathString(path: String)(implicit ctx: Context): JavaClassPath = {
+  def fromPathString(path: String)(implicit ctx: Context): ClassPath = {
     val settings = ctx.settings.classpath.update(path)
     new PathResolver()(ctx.fresh.setSettings(settings)).result
   }
@@ -150,7 +151,11 @@ object PathResolver {
       val pr = new PathResolver()(ctx.fresh.setSettings(sstate))
       println(" COMMAND: 'scala %s'".format(args.mkString(" ")))
       println("RESIDUAL: 'scala %s'\n".format(rest.mkString(" ")))
-      pr.result.show
+
+      pr.result match {
+        case cp: AggregateClassPath =>
+          println(s"ClassPath has ${cp.aggregates.size} entries and results in:\n${cp.asClassPathStrings}")
+      }
     }
   }
 }
@@ -159,7 +164,7 @@ import PathResolver.{ Defaults, Environment, firstNonEmpty, ppcp }
 class PathResolver(implicit ctx: Context) {
   import ctx.base.settings
 
-  val context = ClassPath.DefaultJavaContext
+  private val classPathFactory = new ClassPathFactory
 
   private def cmdLineOrElse(name: String, alt: String) = {
     (commandLineFor(name) match {
@@ -214,7 +219,7 @@ class PathResolver(implicit ctx: Context) {
       else sys.env.getOrElse("CLASSPATH", ".")
     }
 
-    import context._
+    import classPathFactory._
 
     // Assemble the elements!
     // priority class path takes precedence
@@ -254,8 +259,8 @@ class PathResolver(implicit ctx: Context) {
 
   def containers = Calculated.containers
 
-  lazy val result: JavaClassPath = {
-    val cp = new JavaClassPath(containers.toIndexedSeq, context)
+  lazy val result: ClassPath = {
+    val cp = AggregateClassPath(containers.toIndexedSeq)
 
     if (settings.Ylogcp.value) {
       Console.println("Classpath built from " + settings.toConciseString(ctx.sstate))