allow reading and writing to arbitrary streams,...

allow reading and writing to arbitrary streams, not just Console

1 files changed, 31 insertions, 19 deletions

diff --git a/src/compiler/scala/tools/nsc/MainInterpreter.scala b/src/compiler/scala/tools/nsc/MainInterpreter.scala
index 77b7306cc4..cbec6c1479 100644
--- a/src/compiler/scala/tools/nsc/MainInterpreter.scala
+++ b/src/compiler/scala/tools/nsc/MainInterpreter.scala
@@ -5,35 +5,38 @@
 // $Id$
 package scala.tools.nsc
 
-import java.io.{BufferedReader, FileReader, IOException, InputStreamReader}
+import java.io.{BufferedReader, FileReader, IOException, InputStreamReader, PrintWriter}
 import scala.tools.nsc.util.{Position}
 import scala.tools.nsc.reporters.{Reporter, ConsoleReporter}
 
-/** The main class for the new scala interpreter.
- */
-object MainInterpreter {
-  val reporter = new ConsoleReporter()
+/** The main loop of the Scala interpreter.  After instantiation, clients
+  * should call the main() method
+  */
+class InterpreterLoop(in: BufferedReader, out: PrintWriter) {
+  def this() = this(new BufferedReader(new InputStreamReader(System.in)),
+                    new PrintWriter(System.out))
+
+  val reporter = new ConsoleReporter(in, out)
 
   var interpreter: Interpreter = _
 
   /** print a friendly help message */
   def printHelp = {
-    Console.println("This is an interpreter for Scala.")
-    Console.println("Type in expressions to have them evaluated.")
-    Console.println("Type :quit to exit the interpreter.")
-    Console.println("Type :compile followed by a filename to compile a complete Scala file.")
-    Console.println("Type :load followed by a filename to load a sequence of interpreter commands.")
-    Console.println("Type :help to repeat this message later.")
+    out.println("This is an interpreter for Scala.")
+    out.println("Type in expressions to have them evaluated.")
+    out.println("Type :quit to exit the interpreter.")
+    out.println("Type :compile followed by a filename to compile a complete Scala file.")
+    out.println("Type :load followed by a filename to load a sequence of interpreter commands.")
+    out.println("Type :help to repeat this message later.")
   }
 
   /** The main read-eval-print loop for the interpereter.  It calls
       command() for each line of input, and stops when command()
       returns false */
-  def repl: Unit = {
-    val in = new BufferedReader(new InputStreamReader(System.in))
-
+  def repl(): Unit = {
     while(true) {
-      Console.print("\nscala> ")
+      out.print("\nscala> ")
+      out.flush
       var line = in.readLine()
       if(line == null)
         return ()  // assumes null means EOF
@@ -61,7 +64,7 @@ object MainInterpreter {
       new FileReader(filename)
     } catch {
       case _:IOException =>
-        Console.println("Error opening file: " + filename)
+        out.println("Error opening file: " + filename)
         null
     }
     if (fileIn == null) return ()
@@ -82,7 +85,7 @@ object MainInterpreter {
     def withFile(command: String)(action: String => Unit): Unit = {
       val spaceIdx = command.indexOf(' ')
       if (spaceIdx <= 0) {
-        Console.println("That command requires a filename to be specified.")
+        out.println("That command requires a filename to be specified.")
         return ()
       }
       val filename = command.substring(spaceIdx).trim
@@ -95,7 +98,7 @@ object MainInterpreter {
         case ":quit" => return false
         case _ if line.startsWith(":compile") => withFile(line)(f => interpreter.compile(f))
         case _ if line.startsWith(":load") => withFile(line)(f => interpretAllFrom(f))
-        case _ => Console.println("Unknown command.  Type :help for help.")
+        case _ => out.println("Unknown command.  Type :help for help.")
       }
     else if(line.startsWith("#!/")) // skip the first line of Unix scripts
     	()
@@ -125,7 +128,7 @@ object MainInterpreter {
         interpreter.beQuiet
         command.files match {
           case List(filename) => interpretAllFrom(filename)
-          case _ => Console.println(
+          case _ => out.println(
               "Sorry, arguments to interpreter scripts are not currently supported.")
         }
       } else {
@@ -138,3 +141,12 @@ object MainInterpreter {
   }
 
 }
+
+
+/** A wrapper that provides a command-line interface */
+object MainInterpreter {
+ 	def main(args: Array[String]): Unit = {
+     (new InterpreterLoop(new BufferedReader(new InputStreamReader(System.in)),
+                          new PrintWriter(new java.io.FileWriter("out")))).main(args)
+ 	}
+}