1 files changed, 60 insertions, 3 deletions

diff --git a/src/compiler/scala/tools/nsc/interpreter/JLineReader.scala b/src/compiler/scala/tools/nsc/interpreter/JLineReader.scala
index 8f42305bcb..d09567eadf 100644
--- a/src/compiler/scala/tools/nsc/interpreter/JLineReader.scala
+++ b/src/compiler/scala/tools/nsc/interpreter/JLineReader.scala
@@ -7,12 +7,57 @@ package scala.tools.nsc
 package interpreter
 
 import java.io.File
+import java.util.{ List => JList }
 import scala.tools.jline.console.ConsoleReader
 import scala.tools.jline.console.completer._
+import scala.tools.jline.console.history._
+import scala.tools.jline.console.history.{ FileHistory, PersistentHistory, History => JHistory }
+import scala.tools.jline.console.history.History.{ Entry => JEntry }
+import scala.tools.jline.console.ConsoleReader
+import scala.collection.JavaConverters._
+import Properties.userHome
+
+/** A wrapper for JLine's History.
+ */
+class JLineHistory(val jhistory: JHistory) extends History {
+  def asJavaList = jhistory.entries()
+  def asStrings = asList map (_.value.toString)
+  def asList: List[JEntry] = asJavaList.asScala.toList
+  def index = jhistory.index()
+  def size = jhistory.size()
+
+  def grep(s: String) = asStrings filter (_ contains s)
+  def flush() = jhistory match {
+    case x: PersistentHistory => x.flush()
+    case _                    => ()
+  }
+}
+
+object JLineHistory {
+  val ScalaHistoryFile = ".scala_history"
+
+  def apply() = new JLineHistory(
+    try newFile()
+    catch { case x : Exception =>
+      Console.println("Error creating file history: memory history only. " + x)
+      newMemory()
+    }
+  )
+
+  def newMemory() = new MemoryHistory()
+  def newFile() = new FileHistory(new File(userHome, ScalaHistoryFile)) {
+    // flush after every add to avoid installing a shutdown hook.
+    // (The shutdown hook approach also loses history when they aren't run.)
+    override def add(item: CharSequence): Unit = {
+      super.add(item)
+      flush()
+    }
+  }
+}
 
 /** Reads from the console using JLine */
 class JLineReader(val completion: Completion) extends InteractiveReader {
-  lazy val history = History()
+  lazy val history = JLineHistory()
 
   def reset() = consoleReader.getTerminal().reset()
   def init()  = consoleReader.getTerminal().init()
@@ -24,7 +69,12 @@ class JLineReader(val completion: Completion) extends InteractiveReader {
   }
 
   def argCompletor: ArgumentCompleter = {
-    val c = new ArgumentCompleter(new JLineDelimiter, completion.completer())
+    val wrapped = new Completer {
+      val cc = completion.completer()
+      def complete(buffer: String, cursor: Int, candidates: JList[CharSequence]): Int =
+        cc.complete(buffer, cursor, candidates)
+    }
+    val c = new ArgumentCompleter(new JLineDelimiter, wrapped)
     c setStrict false
     c
   }
@@ -37,7 +87,7 @@ class JLineReader(val completion: Completion) extends InteractiveReader {
 
     if (completion ne Completion.Empty) {
       r addCompleter argCompletor
-      r setAutoprintThreshold 250 // max completion candidates without warning
+      r setAutoprintThreshold 400 // max completion candidates without warning
     }
 
     r
@@ -48,3 +98,10 @@ class JLineReader(val completion: Completion) extends InteractiveReader {
   val interactive = true
 }
 
+object JLineReader {
+  def apply(intp: IMain): InteractiveReader = apply(new JLineCompletion(intp))
+  def apply(comp: Completion): InteractiveReader = {
+    try new JLineReader(comp)
+    catch { case e @ (_: Exception | _: NoClassDefFoundError) => new SimpleReader }
+  }
+}