Merge pull request #3285 from som-snytt/issue/8015-FF-NLs

 Count lines by EOLs

2 files changed, 54 insertions, 23 deletions

diff --git a/src/reflect/scala/reflect/internal/util/Position.scala b/src/reflect/scala/reflect/internal/util/Position.scala
index 15cfda26b5..4032ec1157 100644
--- a/src/reflect/scala/reflect/internal/util/Position.scala
+++ b/src/reflect/scala/reflect/internal/util/Position.scala
@@ -202,12 +202,31 @@ private[util] trait InternalPositionImpl {
   def line: Int           = if (hasSource) source.offsetToLine(point) + 1 else 0
   def column: Int         = if (hasSource) calculateColumn() else 0
   def lineContent: String = if (hasSource) source.lineToString(line - 1) else ""
-  def lineCarat: String   = if (hasSource) " " * (column - 1) + "^" else ""
-
-  def showError(msg: String): String = finalPosition match {
-    case FakePos(fmsg) => s"$fmsg $msg"
-    case NoPosition    => msg
-    case pos           => s"${pos.line}: $msg\n${pos.lineContent}\n${pos.lineCarat}"
+  def lineCaret: String   = if (hasSource) " " * (column - 1) + "^" else ""
+  @deprecated("use `lineCaret`", since="2.11.0")
+  def lineCarat: String   = lineCaret
+
+  def showError(msg: String): String = {
+    def escaped(s: String) = {
+      def u(c: Int) = f"\\u$c%04x"
+      def uable(c: Int) = (c < 0x20 && c != '\t') || c == 0x7F
+      if (s exists (c => uable(c))) {
+        val sb = new StringBuilder
+        s foreach (c => sb append (if (uable(c)) u(c) else c))
+        sb.toString
+      } else s
+    }
+    def errorAt(p: Pos) = {
+      def where     = p.line
+      def content   = escaped(p.lineContent)
+      def indicator = p.lineCaret
+      f"$where: $msg%n$content%n$indicator"
+    }
+    finalPosition match {
+      case FakePos(fmsg) => s"$fmsg $msg"
+      case NoPosition    => msg
+      case pos           => errorAt(pos)
+    }
   }
   def showDebug: String = toString
   def show = (
@@ -254,7 +273,7 @@ private[util] trait DeprecatedPosition {
   @deprecated("use `finalPosition`", "2.11.0")
   def inUltimateSource(source: SourceFile): Position = source positionInUltimateSource this
 
-  @deprecated("use `lineCarat`", "2.11.0")
+  @deprecated("use `lineCaret`", since="2.11.0")
   def lineWithCarat(maxWidth: Int): (String, String) = ("", "")
 
   @deprecated("Use `withSource(source)` and `withShift`", "2.11.0")
diff --git a/src/reflect/scala/reflect/internal/util/SourceFile.scala b/src/reflect/scala/reflect/internal/util/SourceFile.scala
index 3b6c57e955..9866b043bb 100644
--- a/src/reflect/scala/reflect/internal/util/SourceFile.scala
+++ b/src/reflect/scala/reflect/internal/util/SourceFile.scala
@@ -16,12 +16,13 @@ import scala.reflect.internal.Chars._
 
 /** abstract base class of a source file used in the compiler */
 abstract class SourceFile {
-  def content : Array[Char]         // normalized, must end in SU
-  def file    : AbstractFile
-  def isLineBreak(idx : Int) : Boolean
+  def content: Array[Char]         // normalized, must end in SU
+  def file   : AbstractFile
+  def isLineBreak(idx: Int): Boolean
+  def isEndOfLine(idx: Int): Boolean
   def isSelfContained: Boolean
   def length : Int
-  def position(offset: Int) : Position = {
+  def position(offset: Int): Position = {
     assert(offset < length, file + ": " + offset + " >= " + length)
     Position.offset(this, offset)
   }
@@ -36,8 +37,12 @@ abstract class SourceFile {
   override def toString() = file.name
   def path = file.path
 
-  def lineToString(index: Int): String =
-    content drop lineToOffset(index) takeWhile (c => !isLineBreakChar(c.toChar)) mkString ""
+  def lineToString(index: Int): String = {
+    val start = lineToOffset(index)
+    var end = start
+    while (!isEndOfLine(end)) end += 1
+    content.slice(start, end) mkString ""
+  }
 
   @tailrec
   final def skipWhitespace(offset: Int): Int =
@@ -52,6 +57,7 @@ object NoSourceFile extends SourceFile {
   def content                   = Array()
   def file                      = NoFile
   def isLineBreak(idx: Int)     = false
+  def isEndOfLine(idx: Int)     = false
   def isSelfContained           = true
   def length                    = -1
   def offsetToLine(offset: Int) = -1
@@ -128,18 +134,24 @@ class BatchSourceFile(val file : AbstractFile, val content0: Array[Char]) extend
       super.identifier(pos)
     }
 
-  def isLineBreak(idx: Int) =
-    if (idx >= length) false else {
-      val ch = content(idx)
-      // don't identify the CR in CR LF as a line break, since LF will do.
-      if (ch == CR) (idx + 1 == length) || (content(idx + 1) != LF)
-      else isLineBreakChar(ch)
-    }
+  private def charAtIsEOL(idx: Int)(p: Char => Boolean) = {
+    // don't identify the CR in CR LF as a line break, since LF will do.
+    def notCRLF0 = content(idx) != CR || idx + 1 >= length || content(idx + 1) != LF
+
+    idx < length && notCRLF0 && p(content(idx))
+  }
+
+  def isLineBreak(idx: Int) = charAtIsEOL(idx)(isLineBreakChar)
+
+  def isEndOfLine(idx: Int) = charAtIsEOL(idx) {
+    case CR | LF => true
+    case _       => false
+  }
 
   def calculateLineIndices(cs: Array[Char]) = {
     val buf = new ArrayBuffer[Int]
     buf += 0
-    for (i <- 0 until cs.length) if (isLineBreak(i)) buf += i + 1
+    for (i <- 0 until cs.length) if (isEndOfLine(i)) buf += i + 1
     buf += cs.length // sentinel, so that findLine below works smoother
     buf.toArray
   }
@@ -149,8 +161,8 @@ class BatchSourceFile(val file : AbstractFile, val content0: Array[Char]) extend
 
   private var lastLine = 0
 
-  /** Convert offset to line in this source file
-   *  Lines are numbered from 0
+  /** Convert offset to line in this source file.
+   *  Lines are numbered from 0.
    */
   def offsetToLine(offset: Int): Int = {
     val lines = lineIndices