SI-7969 Refactor to trait with test

Make REPL classes testable in junit. Test the Tabulator.

2 files changed, 31 insertions, 20 deletions

diff --git a/src/repl/scala/tools/nsc/interpreter/ConsoleReaderHelper.scala b/src/repl/scala/tools/nsc/interpreter/ConsoleReaderHelper.scala
index a4315760a2..2206c8a772 100644
--- a/src/repl/scala/tools/nsc/interpreter/ConsoleReaderHelper.scala
+++ b/src/repl/scala/tools/nsc/interpreter/ConsoleReaderHelper.scala
@@ -8,7 +8,7 @@ package interpreter
 
 import jline.console.{ ConsoleReader, CursorBuffer }
 
-trait ConsoleReaderHelper { _: ConsoleReader =>
+trait ConsoleReaderHelper { _: ConsoleReader with Tabulator =>
   def isAcross: Boolean
 
   def terminal    = getTerminal()
@@ -18,7 +18,8 @@ trait ConsoleReaderHelper { _: ConsoleReader =>
   def readOneKey(prompt: String): Int
   def eraseLine(): Unit
 
-  private val marginSize = 3
+  val marginSize = 3
+
   private def morePrompt = "--More--"
   private def emulateMore(): Int = {
     val key = readOneKey(morePrompt)
@@ -42,21 +43,40 @@ trait ConsoleReaderHelper { _: ConsoleReader =>
   override def printColumns(items: JCollection[_ <: CharSequence]): Unit =
     printColumns_(items: List[String])
 
+  private def printColumns_(items: List[String]): Unit = if (items exists (_ != "")) {
+    val grouped = tabulate(items)
+    var linesLeft  = if (isPaginationEnabled()) height - 1 else Int.MaxValue
+    grouped foreach { xs =>
+      println(xs.mkString)
+      linesLeft -= 1
+      if (linesLeft <= 0) {
+        linesLeft = emulateMore()
+        if (linesLeft < 0)
+          return
+      }
+    }
+  }
+}
+
+trait Tabulator {
+  def isAcross: Boolean
+  def width: Int
+  def marginSize: Int
+
   private def fits(items: List[String], width: Int): Boolean = (
     (items map (_.length)).sum + (items.length - 1) * marginSize < width
   )
-  private def printColumns_(items: List[String]): Unit = if (items exists (_ != "")) {
-    if (fits(items, width)) println(items mkString " " * marginSize)
+  def tabulate(items: List[String]): Seq[Seq[String]] = {
+    if (fits(items, width)) Seq(Seq(items mkString " " * marginSize))
     else printMultiLineColumns(items)
   }
-  private def printMultiLineColumns(items: List[String]): Unit = {
+  private def printMultiLineColumns(items: List[String]): Seq[Seq[String]] = {
     import SimpleMath._
     val longest     = (items map (_.length)).max
     //val shortest   = (items map (_.length)).min
     val columnWidth = longest + marginSize
     val maxcols = {
-      if (isPaginationEnabled) 1
-      else if (columnWidth >= width) 1
+      if (columnWidth >= width) 1
       else 1 max (width / columnWidth)   // make sure it doesn't divide to 0
     }
     val nrows       = items.size /% maxcols
@@ -65,7 +85,8 @@ trait ConsoleReaderHelper { _: ConsoleReader =>
     val padded      = items map (s"%-${columnWidth}s" format _)
     val xwise       = isAcross || ncols > items.length
     val grouped: Seq[Seq[String]]    =
-      if (xwise) (padded grouped groupSize).toSeq
+      if (groupSize == 1) Seq(items)
+      else if (xwise) (padded grouped groupSize).toSeq
       else {
         val h       = 1 max padded.size /% groupSize
         val cols    = (padded grouped h).toList
@@ -73,17 +94,7 @@ trait ConsoleReaderHelper { _: ConsoleReader =>
           for (j <- 0 until groupSize) yield
             if (i < cols(j).size) cols(j)(i) else ""
       }
-
-    var linesLeft  = if (isPaginationEnabled()) height - 1 else Int.MaxValue
-    grouped foreach { xs =>
-      println(xs.mkString)
-      linesLeft -= 1
-      if (linesLeft <= 0) {
-        linesLeft = emulateMore()
-        if (linesLeft < 0)
-          return
-      }
-    }
+    grouped
   }
 }
 
diff --git a/src/repl/scala/tools/nsc/interpreter/JLineReader.scala b/src/repl/scala/tools/nsc/interpreter/JLineReader.scala
index 970efc1282..e50c7d3e0a 100644
--- a/src/repl/scala/tools/nsc/interpreter/JLineReader.scala
+++ b/src/repl/scala/tools/nsc/interpreter/JLineReader.scala
@@ -33,7 +33,7 @@ class JLineReader(_completion: => Completion) extends InteractiveReader {
     }
   }
 
-  class JLineConsoleReader extends ConsoleReader with ConsoleReaderHelper {
+  class JLineConsoleReader extends ConsoleReader with ConsoleReaderHelper with Tabulator {
     val isAcross = interpreter.`package`.isAcross
 
     this setPaginationEnabled interpreter.`package`.isPaged