Enable flat classpath by default

Implements VirtualDirectoryFlatClassPath, which is required for the
presentation compiler created for the repl's tab-completion.

Various minor cleanups in the flat classpath implementation.

1 files changed, 25 insertions, 9 deletions

diff --git a/src/repl/scala/tools/nsc/interpreter/PresentationCompilation.scala b/src/repl/scala/tools/nsc/interpreter/PresentationCompilation.scala
index c8cd201bf5..e3dc72b717 100644
--- a/src/repl/scala/tools/nsc/interpreter/PresentationCompilation.scala
+++ b/src/repl/scala/tools/nsc/interpreter/PresentationCompilation.scala
@@ -5,12 +5,14 @@
 package scala.tools.nsc.interpreter
 
 import scala.reflect.internal.util.RangePosition
+import scala.reflect.io.AbstractFile
 import scala.tools.nsc.backend.JavaPlatform
+import scala.tools.nsc.settings.ClassPathRepresentationType
+import scala.tools.nsc.util.ClassPath.DefaultJavaContext
+import scala.tools.nsc.util.{ClassPath, MergedClassPath, DirectoryClassPath}
 import scala.tools.nsc.{interactive, Settings}
-import scala.tools.nsc.io._
 import scala.tools.nsc.reporters.StoreReporter
-import scala.tools.nsc.util.ClassPath.DefaultJavaContext
-import scala.tools.nsc.util.{DirectoryClassPath, MergedClassPath}
+import scala.tools.nsc.classpath._
 
 trait PresentationCompilation {
   self: IMain =>
@@ -55,8 +57,14 @@ trait PresentationCompilation {
     * You may downcast the `reporter` to `StoreReporter` to access type errors.
     */
   def newPresentationCompiler(): interactive.Global = {
-    val replOutClasspath: DirectoryClassPath = new DirectoryClassPath(replOutput.dir, DefaultJavaContext)
-    val mergedClasspath = new MergedClassPath[AbstractFile](replOutClasspath :: global.platform.classPath :: Nil, DefaultJavaContext)
+    def mergedFlatClasspath = {
+      val replOutClasspath = FlatClassPathFactory.newClassPath(replOutput.dir, settings)
+      AggregateFlatClassPath(replOutClasspath :: global.platform.flatClassPath :: Nil)
+    }
+    def mergedRecursiveClasspath = {
+      val replOutClasspath: DirectoryClassPath = new DirectoryClassPath(replOutput.dir, DefaultJavaContext)
+      new MergedClassPath[AbstractFile](replOutClasspath :: global.platform.classPath :: Nil, DefaultJavaContext)
+    }
     def copySettings: Settings = {
       val s = new Settings(_ => () /* ignores "bad option -nc" errors, etc */)
       s.processArguments(global.settings.recreateArgs, processAll = false)
@@ -65,10 +73,18 @@ trait PresentationCompilation {
     }
     val storeReporter: StoreReporter = new StoreReporter
     val interactiveGlobal = new interactive.Global(copySettings, storeReporter) { self =>
-      override lazy val platform: ThisPlatform = new JavaPlatform {
-        val global: self.type = self
-
-        override def classPath: PlatformClassPath = mergedClasspath
+      override lazy val platform: ThisPlatform = {
+        if (settings.YclasspathImpl.value == ClassPathRepresentationType.Flat) {
+          new JavaPlatform {
+            val global: self.type = self
+            override private[nsc] lazy val flatClassPath: FlatClassPath = mergedFlatClasspath
+          }
+        } else {
+          new JavaPlatform {
+            val global: self.type = self
+            override def classPath: ClassPath[AbstractFile] = mergedRecursiveClasspath
+          }
+        }
       }
     }
     new interactiveGlobal.TyperRun()