Add loader support for dotty bridge

Author: felixmulder

bridge/src/main/scala/xsbt/ConsoleInterface.scala

@@ -9,6 +9,7 @@ import scala.tools.nsc.interpreter.InteractiveReader
 import scala.tools.nsc.reporters.Reporter
 import scala.tools.nsc.util.ClassPath
 
+import dotty.tools.dotc.core.Contexts.Context
 import dotty.tools.dotc.repl.REPL
 import dotty.tools.dotc.repl.REPL.Config
 
@@ -39,7 +40,8 @@ class ConsoleInterface {
     val repl = ConsoleInterface.customRepl(
       initialCommands :: Nil,
       cleanupCommands :: Nil,
-      bindNames zip bindValues
+      bindNames zip bindValues,
+      loader
     )
     repl.process(completeArgs)
   }
@@ -49,11 +51,13 @@ object ConsoleInterface {
   def customConfig(
     initCmds: List[String],
     cleanupCmds: List[String],
-    boundVals: Array[(String, Any)]
+    boundVals: Array[(String, Any)],
+    loader: ClassLoader
   ) = new Config {
     override val initialCommands: List[String] = initCmds
     override val cleanupCommands: List[String] = cleanupCmds
     override val boundValues: Array[(String, Any)] = boundVals
+    override val classLoader: Option[ClassLoader] = Option(loader)
   }
 
   def customRepl(cfg: Config): REPL = new REPL {
@@ -63,6 +67,7 @@ object ConsoleInterface {
   def customRepl(
     initCmds: List[String],
     cleanupCmds: List[String],
-    boundVals: Array[(String, Any)]
-  ): REPL = customRepl(customConfig(initCmds, cleanupCmds, boundVals))
+    boundVals: Array[(String, Any)],
+    loader: ClassLoader
+  ): REPL = customRepl(customConfig(initCmds, cleanupCmds, boundVals, loader))
 }

src/dotty/tools/dotc/repl/CompilingInterpreter.scala

@@ -60,7 +60,11 @@ import printing.SyntaxHighlighting
  * @param ictx  The context to use for initialization of the interpreter,
  *              needed to access the current classpath.
  */
-class CompilingInterpreter(out: PrintWriter, ictx: Context) extends Compiler with Interpreter {
+class CompilingInterpreter(
+  out: PrintWriter,
+  ictx: Context,
+  parentClassLoader: Option[ClassLoader]
+) extends Compiler with Interpreter {
   import ast.untpd._
   import CompilingInterpreter._
 
@@ -136,8 +140,6 @@ class CompilingInterpreter(out: PrintWriter, ictx: Context) extends Compiler wit
   /** the compiler's classpath, as URL's */
   val compilerClasspath: List[URL] = ictx.platform.classPath(ictx).asURLs
 
-  protected def parentClassLoader: ClassLoader = classOf[Interpreter].getClassLoader
-
   /* A single class loader is used for all commands interpreted by this Interpreter.
      It would also be possible to create a new class loader for each command
      to interpret.  The advantages of the current approach are:
@@ -153,8 +155,10 @@ class CompilingInterpreter(out: PrintWriter, ictx: Context) extends Compiler wit
   */
   /** class loader used to load compiled code */
   val classLoader: ClassLoader = {
-    val parent = new URLClassLoader(compilerClasspath.toArray, parentClassLoader)
-    new AbstractFileClassLoader(virtualDirectory, parent)
+    lazy val parent = new URLClassLoader(compilerClasspath.toArray,
+                                         classOf[Interpreter].getClassLoader)
+
+    new AbstractFileClassLoader(virtualDirectory, parentClassLoader.getOrElse(parent))
   }
 
   // Set the current Java "context" class loader to this interpreter's class loader

src/dotty/tools/dotc/repl/REPL.scala

@@ -4,7 +4,10 @@ package repl
 
 import core.Contexts.Context
 import reporting.Reporter
-import java.io.{BufferedReader, File, FileReader, PrintWriter}
+import io.{AbstractFile, PlainFile, VirtualDirectory}
+import scala.reflect.io.{PlainDirectory, Directory}
+import java.io.{BufferedReader, File => JFile, FileReader, PrintWriter}
+import java.net.{URL, URLClassLoader}
 
 /** A compiler which stays resident between runs.
  *  Usage:
@@ -31,7 +34,7 @@ class REPL extends Driver {
   }
 
   override def newCompiler(implicit ctx: Context): Compiler =
-    new repl.CompilingInterpreter(config.output, ctx)
+    new repl.CompilingInterpreter(config.output, ctx, config.classLoader)
 
   override def sourcesRequired = false
 
@@ -80,6 +83,9 @@ object REPL {
      */
     val boundValues: Array[(String, Any)] = Array.empty[(String, Any)]
 
+    /** To pass a custom ClassLoader to the Dotty REPL, overwride this value */
+    val classLoader: Option[ClassLoader] = None
+
     /** The default input reader */
     def input(in: Interpreter)(implicit ctx: Context): InteractiveReader = {
       val emacsShell = System.getProperty("env.emacs", "") != ""