Move JLine apis into LineReader

It is better that sbt not expose the implementation detail that
LineReader is implemented by JLine. Other terminal related apis should
be handled by sbt.internal.util.Terminal.

internal/util-complete/src/main/scala/sbt/internal/util/LineReader.scala

@@ -16,6 +16,36 @@ import sbt.internal.util.complete.Parser
 import scala.annotation.tailrec
 import scala.concurrent.duration._
 
+trait LineReader {
+  def readLine(prompt: String, mask: Option[Char] = None): Option[String]
+  def redraw(): Unit = ()
+}
+
+object LineReader {
+  val HandleCONT =
+    !java.lang.Boolean.getBoolean("sbt.disable.cont") && Signals.supported(Signals.CONT)
+  val MaxHistorySize = 500
+
+  def createReader(historyPath: Option[File], in: InputStream): ConsoleReader = {
+    val cr = Terminal.createReader(in)
+    cr.setExpandEvents(false) // https://issues.scala-lang.org/browse/SI-7650
+    cr.setBellEnabled(false)
+    val h = historyPath match {
+      case None       => new MemoryHistory
+      case Some(file) => new FileHistory(file): MemoryHistory
+    }
+    h.setMaxSize(MaxHistorySize)
+    cr.setHistory(h)
+    cr
+  }
+
+  def simple(
+      historyPath: Option[File],
+      handleCONT: Boolean = HandleCONT,
+      injectThreadSleep: Boolean = false
+  ): LineReader = new SimpleReader(historyPath, handleCONT, injectThreadSleep)
+}
+
 abstract class JLine extends LineReader {
   protected[this] def handleCONT: Boolean
   protected[this] def reader: ConsoleReader
@@ -92,6 +122,7 @@ abstract class JLine extends LineReader {
   }
 }
 
+@deprecated("Use LineReader apis", "1.4.0")
 private[sbt] object JLine {
   @deprecated("For binary compatibility only", "1.4.0")
   protected[this] val originalIn = new FileInputStream(FileDescriptor.in)
@@ -117,8 +148,10 @@ private[sbt] object JLine {
   def usingTerminal[T](f: jline.Terminal => T): T =
     Terminal.withCanonicalIn(f(Terminal.deprecatedTeminal))
 
+  @deprecated("unused", "1.4.0")
   def createReader(): ConsoleReader = createReader(None, Terminal.wrappedSystemIn)
 
+  @deprecated("Use LineReader.createReader", "1.4.0")
   def createReader(historyPath: Option[File], in: InputStream): ConsoleReader = {
     val cr = Terminal.createReader(in)
     cr.setExpandEvents(false) // https://issues.scala-lang.org/browse/SI-7650
@@ -135,16 +168,18 @@ private[sbt] object JLine {
   @deprecated("Avoid referencing JLine directly. Use Terminal.withRawSystemIn instead.", "1.4.0")
   def withJLine[T](action: => T): T = Terminal.withRawSystemIn(action)
 
+  @deprecated("Use LineReader.simple instead", "1.4.0")
   def simple(
       historyPath: Option[File],
-      handleCONT: Boolean = HandleCONT,
+      handleCONT: Boolean = LineReader.HandleCONT,
       injectThreadSleep: Boolean = false
   ): SimpleReader = new SimpleReader(historyPath, handleCONT, injectThreadSleep)
 
-  val MaxHistorySize = 500
+  @deprecated("Use LineReader.MaxHistorySize", "1.4.0")
+  val MaxHistorySize = LineReader.MaxHistorySize
 
-  val HandleCONT =
+  @deprecated("Use LineReader.HandleCONT", "1.4.0")
-    !java.lang.Boolean.getBoolean("sbt.disable.cont") && Signals.supported(Signals.CONT)
+  val HandleCONT = LineReader.HandleCONT
 }
 
 @deprecated("For binary compatibility only", "1.4.0")
@@ -172,11 +207,6 @@ private[sbt] class InputStreamWrapper(is: InputStream, val poll: Duration)
     }
 }
 
-trait LineReader {
-  def readLine(prompt: String, mask: Option[Char] = None): Option[String]
-  def redraw(): Unit = ()
-}
-
 final class FullReader(
     historyPath: Option[File],
     complete: Parser[_],
@@ -187,11 +217,11 @@ final class FullReader(
   def this(
       historyPath: Option[File],
       complete: Parser[_],
-      handleCONT: Boolean = JLine.HandleCONT,
+      handleCONT: Boolean = LineReader.HandleCONT,
       injectThreadSleep: Boolean = false
   ) = this(historyPath, complete, handleCONT, JLine.makeInputStream(injectThreadSleep))
   protected[this] val reader: ConsoleReader = {
-    val cr = JLine.createReader(historyPath, inputStream)
+    val cr = LineReader.createReader(historyPath, inputStream)
     sbt.internal.util.complete.JLineCompletion.installCustomCompletor(cr, complete)
     cr
   }
@@ -205,7 +235,7 @@ class SimpleReader private[sbt] (
   def this(historyPath: Option[File], handleCONT: Boolean, injectThreadSleep: Boolean) =
     this(historyPath, handleCONT, Terminal.wrappedSystemIn)
   protected[this] val reader: ConsoleReader =
-    JLine.createReader(historyPath, inputStream)
+    LineReader.createReader(historyPath, inputStream)
 }
 
-object SimpleReader extends SimpleReader(None, JLine.HandleCONT, false)
+object SimpleReader extends SimpleReader(None, LineReader.HandleCONT, false)

main-command/src/main/scala/sbt/BasicCommands.scala

@@ -9,7 +9,7 @@ package sbt
 
 import java.nio.file.Paths
 import sbt.util.Level
-import sbt.internal.util.{ AttributeKey, FullReader, JLine, Terminal }
+import sbt.internal.util.{ AttributeKey, FullReader, LineReader, Terminal }
 import sbt.internal.util.complete.{
   Completion,
   Completions,
@@ -34,7 +34,9 @@ import BasicKeys._
 import java.io.File
 
 import sbt.io.IO
+import sbt.util.Level
 
+import scala.Function.tupled
 import scala.collection.mutable.ListBuffer
 import scala.util.control.NonFatal
 
@@ -374,7 +376,7 @@ object BasicCommands {
     val history = (s get historyPath) getOrElse (new File(s.baseDir, ".history")).some
     val prompt = (s get shellPrompt) match { case Some(pf) => pf(s); case None => "> " }
     val reader =
-      new FullReader(history, s.combinedParser, JLine.HandleCONT, Terminal.wrappedSystemIn)
+      new FullReader(history, s.combinedParser, LineReader.HandleCONT, Terminal.wrappedSystemIn)
     val line = reader.readLine(prompt)
     line match {
       case Some(line) =>

main-command/src/main/scala/sbt/internal/ConsoleChannel.scala

@@ -29,7 +29,12 @@ private[sbt] final class ConsoleChannel(val name: String) extends CommandChannel
     private val history = s.get(historyPath).getOrElse(Some(new File(s.baseDir, ".history")))
     private val prompt = getPrompt(s)
     private val reader =
-      new FullReader(history, s.combinedParser, JLine.HandleCONT, Terminal.throwOnClosedSystemIn)
+      new FullReader(
+        history,
+        s.combinedParser,
+        LineReader.HandleCONT,
+        Terminal.throwOnClosedSystemIn
+      )
     setDaemon(true)
     start()
     override def run(): Unit =

main-command/src/main/scala/sbt/internal/client/NetworkClient.scala

@@ -15,7 +15,7 @@ import java.util.concurrent.atomic.{ AtomicBoolean, AtomicReference }
 
 import sbt.internal.langserver.{ LogMessageParams, MessageType, PublishDiagnosticsParams }
 import sbt.internal.protocol._
-import sbt.internal.util.{ ConsoleAppender, JLine }
+import sbt.internal.util.{ ConsoleAppender, LineReader }
 import sbt.io.IO
 import sbt.io.syntax._
 import sbt.protocol._
@@ -216,7 +216,7 @@ class NetworkClient(configuration: xsbti.AppConfiguration, arguments: List[Strin
   }
 
   def shell(): Unit = {
-    val reader = JLine.simple(None, JLine.HandleCONT, injectThreadSleep = true)
+    val reader = LineReader.simple(None, LineReader.HandleCONT, injectThreadSleep = true)
     while (running.get) {
       reader.readLine("> ", None) match {
         case Some("shutdown") =>