Merge pull request scala#4762 from retronym/topic/completely-2.12

Remove the old REPL tab completion implementation

Author: retronym

src/compiler/scala/tools/nsc/settings/ScalaSettings.scala

@@ -172,7 +172,6 @@ trait ScalaSettings extends AbsScalaSettings
   val YconstOptimization  = BooleanSetting    ("-Yconst-opt", "Perform optimization with constant values.")
   val Ycompacttrees   = BooleanSetting    ("-Ycompact-trees", "Use compact tree printer when displaying trees.")
   val noCompletion    = BooleanSetting    ("-Yno-completion", "Disable tab-completion in the REPL.")
-  val completion      = ChoiceSetting     ("-Ycompletion", "provider", "Select tab-completion in the REPL.", List("pc","adhoc","none"), "pc")
   val Xdce            = BooleanSetting    ("-Ydead-code", "Perform dead code elimination.")
   val debug           = BooleanSetting    ("-Ydebug", "Increase the quantity of debugging output.")
   //val doc           = BooleanSetting    ("-Ydoc", "Generate documentation")

src/repl-jline/scala/tools/nsc/interpreter/jline/JLineReader.scala

@@ -16,7 +16,7 @@ import jconsole.history.{History => JHistory}
 
 
 import scala.tools.nsc.interpreter
-import scala.tools.nsc.interpreter.{Completion, JLineCompletion, NoCompletion}
+import scala.tools.nsc.interpreter.{Completion, NoCompletion}
 import scala.tools.nsc.interpreter.Completion.Candidates
 import scala.tools.nsc.interpreter.session.History
 
@@ -125,21 +125,16 @@ private class JLineConsoleReader extends jconsole.ConsoleReader with interpreter
     // adapt the JLine completion interface
     def completer =
       new Completer {
-        val tc = completion.completer()
+        val tc = completion
         def complete(_buf: String, cursor: Int, candidates: JList[CharSequence]): Int = {
           val buf = if (_buf == null) "" else _buf
-          val Candidates(newCursor, newCandidates) = tc.complete(buf, cursor)
+          val Candidates(newCursor, newCandidates) = completion.complete(buf, cursor)
           newCandidates foreach (candidates add _)
           newCursor
         }
       }
 
-    // a last bit of nastiness: parsing help depending on the flavor of completer (fixme)
     completion match {
-      case _: JLineCompletion =>
-        val jlineCompleter = new ArgumentCompleter(new JLineDelimiter, completer)
-        jlineCompleter setStrict false
-        this addCompleter jlineCompleter
       case NoCompletion       => ()
       case _                  => this addCompleter completer
     }

src/repl/scala/tools/nsc/interpreter/Completion.scala

@@ -13,35 +13,22 @@ import Completion._
  */
 trait Completion {
   def resetVerbosity(): Unit
-  def completer(): ScalaCompleter
+  def complete(buffer: String, cursor: Int): Candidates
 }
 object NoCompletion extends Completion {
   def resetVerbosity() = ()
-  def completer() = NullCompleter
+  def complete(buffer: String, cursor: Int) = NoCandidates
 }
 
 object Completion {
   case class Candidates(cursor: Int, candidates: List[String]) { }
   val NoCandidates = Candidates(-1, Nil)
 
-  object NullCompleter extends ScalaCompleter {
-    def complete(buffer: String, cursor: Int): Candidates = NoCandidates
-  }
-  trait ScalaCompleter {
-    def complete(buffer: String, cursor: Int): Candidates
-  }
-
   def looksLikeInvocation(code: String) = (
         (code != null)
     &&  (code startsWith ".")
     && !(code == ".")
     && !(code startsWith "./")
     && !(code startsWith "..")
   )
-  object Forwarder {
-    def apply(forwardTo: () => Option[CompletionAware]): CompletionAware = new CompletionAware {
-      def completions(verbosity: Int) = forwardTo() map (_ completions verbosity) getOrElse Nil
-      override def follow(s: String) = forwardTo() flatMap (_ follow s)
-    }
-  }
 }

src/repl/scala/tools/nsc/interpreter/CompletionAware.scala

@@ -840,12 +840,7 @@ class ILoop(in0: Option[BufferedReader], protected val out: JPrintWriter)
       }
 
       def mkReader(maker: ReaderMaker) = maker { () =>
-        settings.completion.value match {
-          case _ if settings.noCompletion => NoCompletion
-          case "none"   => NoCompletion
-          case "adhoc"  => new JLineCompletion(intp) // JLineCompletion is a misnomer; it's not tied to jline
-          case "pc" | _ => new PresentationCompilerCompleter(intp)
-        }
+        if (settings.noCompletion) NoCompletion else new PresentationCompilerCompleter(intp)
       }
 
       def internalClass(kind: String) = s"scala.tools.nsc.interpreter.$kind.InteractiveReader"