Make FancyConsoleReporter and Highlighting obey color setting

Fancy console reporter and the string interpolator for highlighting now
obey the color setting - this means that the next step towards unifying
the reporters is to make sure the tests work with
`FancyConsoleReporter` under the `-color:never` flag.

Author: felixmulder

src/dotty/tools/dotc/printing/Highlighting.scala

@@ -3,36 +3,47 @@ package dotc
 package printing
 
 import scala.collection.mutable
+import core.Contexts.Context
 
 object Highlighting {
 
-  implicit def highlightToString(h: Highlight): String = h.toString
-  implicit def hbufToString(hb: HighlightBuffer): String = hb.toString
+  implicit def highlightShow(h: Highlight)(implicit ctx: Context): String =
+    h.show
+  implicit def highlightToString(h: Highlight): String =
+    h.toString
+  implicit def hbufToString(hb: HighlightBuffer): String =
+    hb.toString
 
   abstract class Highlight(private val highlight: String) {
     def text: String
 
-    override def toString = highlight + text + Console.RESET
+    def show(implicit ctx: Context) =
+      if (ctx.settings.color.value == "never") text
+      else highlight + text + Console.RESET
 
-    def +(other: Highlight): HighlightBuffer =
+    override def toString =
+      highlight + text + Console.RESET
+
+    def +(other: Highlight)(implicit ctx: Context): HighlightBuffer =
       new HighlightBuffer(this) + other
 
-    def +(other: String): HighlightBuffer =
+    def +(other: String)(implicit ctx: Context): HighlightBuffer =
       new HighlightBuffer(this) + other
   }
 
   abstract class Modifier(private val mod: String, text: String) extends Highlight(Console.RESET) {
-    override def toString =
-      mod + super.toString
+    override def show(implicit ctx: Context) =
+      if (ctx.settings.color.value == "never") ""
+      else mod + super.show
   }
 
-  case class HighlightBuffer(hl: Highlight) {
+  case class HighlightBuffer(hl: Highlight)(implicit ctx: Context) {
     val buffer = new mutable.ListBuffer[String]
 
-    buffer += hl.toString
+    buffer += hl.show
 
     def +(other: Highlight): HighlightBuffer = {
-      buffer += other.toString
+      buffer += other.show
       this
     }
 
@@ -45,6 +56,8 @@ object Highlighting {
       buffer.mkString
   }
 
+  case class NoColor(text: String) extends Highlight(Console.RESET)
+
   case class Red(text: String) extends Highlight(Console.RED)
   case class Blue(text: String) extends Highlight(Console.BLUE)
   case class Cyan(text: String) extends Highlight(Console.CYAN)

src/dotty/tools/dotc/printing/SyntaxHighlighting.scala

@@ -6,14 +6,20 @@ import parsing.Tokens._
 import scala.annotation.switch
 import scala.collection.mutable.StringBuilder
 import core.Contexts.Context
+import Highlighting.{Highlight, HighlightBuffer}
 
 /** This object provides functions for syntax highlighting in the REPL */
 object SyntaxHighlighting {
 
   implicit class SyntaxFormatting(val sc: StringContext) extends AnyVal {
-    def hl(args: Any*)(implicit ctx: Context): String =
+    def hl(args: Any*)(implicit ctx: Context): String = {
       if (ctx.settings.color.value == "never") sc.s(args: _*)
-      else sc.s(args.map(x => new String(apply(x.toString).toArray)): _*)
+      else sc.s(args.map ({
+        case hl: Highlight => hl.show
+        case hb: HighlightBuffer => hb.toString
+        case x => new String(apply(x.toString).toArray)
+      }): _*)
+    }
   }
 
   val NoColor         = Console.RESET

src/dotty/tools/dotc/reporting/ConsoleReporter.scala

@@ -44,7 +44,7 @@ class ConsoleReporter(
     }
   }
 
-  def printExplanation(m: Message): Unit =
+  def printExplanation(m: Message)(implicit ctx: Context): Unit =
     printMessage(
       s"""|
           |Explanation

src/dotty/tools/dotc/reporting/FancyConsoleReporter.scala

@@ -21,29 +21,29 @@ class FancyConsoleReporter(
   writer: PrintWriter = new PrintWriter(Console.err, true)
 ) extends ConsoleReporter(reader, writer) {
 
+  def stripColor(str: String): String =
+    str.replaceAll("\u001B\\[[;\\d]*m", "")
+
   def sourceLine(pos: SourcePosition)(implicit ctx: Context): (String, Int) = {
     val lineNum = s"${pos.line}:"
     (lineNum + hl"${pos.lineContent.stripLineEnd}", lineNum.length)
   }
 
-  def columnMarker(pos: SourcePosition, offset: Int) =
+  def columnMarker(pos: SourcePosition, offset: Int)(implicit ctx: Context) =
     if (pos.startLine == pos.endLine) {
       val whitespace = " " * (pos.column + offset)
       val carets =
-        AnnotationColor +
-        ("^" * math.max(1, pos.endColumn - pos.startColumn)) +
-        NoColor
+        Red("^" * math.max(1, pos.endColumn - pos.startColumn))
 
-      whitespace + carets
+      whitespace + carets.show
     } else {
-      " " * (pos.column + offset) + AnnotationColor + "^" + NoColor
+      Red(" " * (pos.column + offset) + "^").show
     }
 
   def errorMsg(pos: SourcePosition, msg: String, offset: Int)(implicit ctx: Context) = {
     var hasLongLines = false
     val leastWhitespace = msg.lines.foldLeft(Int.MaxValue) { (minPad, line) =>
-      val lineLength =
-        line.replaceAll("\u001B\\[[;\\d]*m", "").length
+      val lineLength = stripColor(line).length
       val padding =
         math.min(math.max(0, ctx.settings.pageWidth.value - offset - lineLength), offset + pos.startColumn)
 
@@ -60,11 +60,10 @@ class FancyConsoleReporter(
   def posStr(pos: SourcePosition, kind: String)(implicit ctx: Context) =
     if (pos.exists) Blue({
       val file = pos.source.file.toString
-
       val prefix = s"-- $kind: $file "
       prefix +
-      ("-" * math.max(ctx.settings.pageWidth.value - prefix.replaceAll("\u001B\\[[;\\d]*m", "").length, 0))
-    }).toString else ""
+      ("-" * math.max(ctx.settings.pageWidth.value - stripColor(prefix).length, 0))
+    }).show else ""
 
   /** Prints the message with the given position indication. */
   override def printMessageAndPos(msg: String, pos: SourcePosition, kind: String = "")(implicit ctx: Context): Unit = {
@@ -78,23 +77,22 @@ class FancyConsoleReporter(
     } else printMessage(msg)
   }
 
-  override def printExplanation(m: Message): Unit =
-    printMessage(
-      s"""|
-          |${Blue("Explanation")}
-          |${Blue("===========")}
-          |${m.explanation}""".stripMargin
-    )
+  override def printExplanation(m: Message)(implicit ctx: Context): Unit = {
+    printMessage(hl"""|
+                      |${Blue("Explanation")}
+                      |${Blue("===========")}""".stripMargin)
+    printMessage(m.explanation)
+  }
 
 
-  override def summary: String = {
+  override def summary(implicit ctx: Context): String = {
     val b = new mutable.ListBuffer[String]
     if (warningCount > 0)
-      b += countString(warningCount, Yellow("warning")) + " found"
+      b += countString(warningCount, Yellow("warning").show) + " found"
     if (errorCount > 0)
-      b += countString(errorCount, Red("error")) + " found"
+      b += countString(errorCount, Red("error").show) + " found"
     for ((settingName, count) <- unreportedWarnings)
-      b += s"there were $count ${settingName.tail} ${Yellow("warning(s)")}; re-run with $settingName for details"
+      b += s"there were $count ${settingName.tail} ${Yellow("warning(s)").show}; re-run with $settingName for details"
     b.mkString("\n")
   }
 }

src/dotty/tools/dotc/reporting/Reporter.scala

@@ -243,7 +243,7 @@ abstract class Reporter extends interfaces.ReporterResult {
 
 
   /** Summary of warnings and errors */
-  def summary: String = {
+  def summary(implicit ctx: Context): String = {
     val b = new mutable.ListBuffer[String]
     if (warningCount > 0)
       b += countString(warningCount, "warning") + " found"