Fixes scala-ide#93 - Editor cut-off value is now applied per-evaluation

dotta · Oct 16, 2012 · df4eada · df4eada
1 parent c00e791
commit df4eada
Showing 1 changed file with 42 additions and 18 deletions.
diff --git a/org.scalaide.worksheet/src/org/scalaide/worksheet/runtime/IncrementalDocumentMixer.scala b/org.scalaide.worksheet/src/org/scalaide/worksheet/runtime/IncrementalDocumentMixer.scala
@@ -2,28 +2,29 @@ package org.scalaide.worksheet.runtime
 
 import java.io.Writer
 
-import scala.actors.{ Actor, DaemonActor, TIMEOUT }
+import scala.actors.{Actor, DaemonActor, TIMEOUT}
+import scala.collection.mutable.LinkedHashMap
+import scala.collection.mutable.ListBuffer
 import scala.tools.eclipse.logging.HasLogger
 
 import org.scalaide.worksheet.editor.DocumentHolder
 import org.scalaide.worksheet.text.{ Mixer, SourceInserter }
 
 object IncrementalDocumentMixer {
-  def apply(editor: DocumentHolder, source: Writer, maxOutput: Int = MaximumOutputChars): Actor = {
+  def apply(editor: DocumentHolder, source: Writer, maxOutput: Int): Actor = {
     val incrementalMixer = new IncrementalDocumentMixer(editor, source, maxOutput)
     incrementalMixer.start()
     incrementalMixer
   }
 
-  final val RefreshDocumentTimeout = 200
-  final val MaximumOutputChars = 100
+  private final val RefreshDocumentTimeout = 200
 
   /** How many ticks should pass with output not changing before adding a spinner? */
-  final val InfiniteLoopTicks = 1000 / RefreshDocumentTimeout // 1 sec
+  private final val InfiniteLoopTicks = 1000 / RefreshDocumentTimeout // 1 sec
 }
 
 private class IncrementalDocumentMixer private (editor: DocumentHolder, source: Writer, val maximumOutputSize: Int) extends DaemonActor with HasLogger {
-  import IncrementalDocumentMixer.{ RefreshDocumentTimeout, InfiniteLoopTicks }
+  import IncrementalDocumentMixer.{ RefreshDocumentTimeout, InfiniteLoopTicks}
 
   private val originalContent = editor.getContents
   private val stripped = SourceInserter.stripRight(editor.getContents.toCharArray)
@@ -45,7 +46,7 @@ private class IncrementalDocumentMixer private (editor: DocumentHolder, source:
 
   private def updateDocument(newText: String): Unit = {
     if (newText.length > 0) {
-      val (mixed, lastInsertion) = mixer.mix(stripped, showLongRunning(pruneOutput(newText)).toCharArray())
+      val (mixed, lastInsertion) = mixer.mix(stripped, showLongRunning(pruneOutputPerEvaluation(newText)).toCharArray())
       editor.replaceWith(mixed.mkString, lastInsertion)
     }
   }
@@ -73,17 +74,40 @@ private class IncrementalDocumentMixer private (editor: DocumentHolder, source:
     }
   }
 
-  def pruneOutput(newText: String): String = {
-    if (newText.length() > maximumOutputSize) {
-      val lastNL = newText.indexOf('\n', maximumOutputSize)
-      val endPos = if (lastNL == -1) newText.length else lastNL
-      val displayableText = newText.substring(0, endPos)
-      val suffix = if (displayableText.last == '\n') "" else "\n"
-      val lastLine = displayableText.lines.toSeq.last
-      val offset = lastLine.substring(0, lastLine.indexOf(' ', 0))
-      logger.debug("Cutting off large output at position: " + offset)
-      displayableText + suffix + offset + " Output exceeds cutoff limit. "
-    } else newText
+  def pruneOutputPerEvaluation(newText: String): String = {
+    // Extracts the offset prefixed to each line in the evaluation output 
+    object Offset {
+      private val offsetExtractor = """^(\d*)""".r
+      def unapply(line: String): Option[String] = offsetExtractor.findFirstIn(line)
+    }
+    // Groups together `lines` that share the same offset  
+    def groupLinesByOffset(lines: List[String], acc: LinkedHashMap[String, ListBuffer[String]]): LinkedHashMap[String, ListBuffer[String]] = lines match {
+      case Nil => acc
+      case line :: rest =>
+        groupLinesByOffset(rest, 
+          line match {
+            case Offset(offset) =>
+              acc.get(offset) match {
+                case None => acc += (offset -> ListBuffer(line))
+                case Some(result) => acc += ((offset, result += line))
+              }
+
+            case _ =>
+              logger.error("Discarded evaluation result, this is a bug. Please open a ticket and make sure to provide the worksheet source that generated this warning.")
+              acc
+        })    
+    }
+
+    val lines = newText.split('\n')
+    val linesByOffset = groupLinesByOffset(lines.toList, LinkedHashMap.empty)
+
+    val evaluationResults = for((_, evaluationOutputs) <- linesByOffset) yield {
+      val evaluationResult = evaluationOutputs.mkString("\n")
+      (if(evaluationResult.length <= maximumOutputSize) evaluationResult
+      else evaluationResult.take(maximumOutputSize) + " Output exceeds cutoff limit. ")
+    }
+
+    evaluationResults.mkString("\n")
   }
 
   override def toString: String = "IncrementalDocumentMixer <actor>"