Fix #3655: Remove hl interpolator

Author: OlivierBlanvillain

compiler/src/dotty/tools/dotc/ast/Desugar.scala

@@ -14,6 +14,7 @@ import collection.mutable.ListBuffer
 import reporting.diagnostic.messages._
 import reporting.trace
 import annotation.constructorOnly
+import printing.Formatting.hl
 
 import scala.annotation.internal.sharable
 
@@ -762,12 +763,12 @@ object desugar {
     def flagSourcePos(flag: FlagSet) = mods.mods.find(_.flags == flag).fold(mdef.sourcePos)(_.sourcePos)
 
     if (mods.is(Abstract))
-      ctx.error(hl"""$Abstract modifier cannot be used for objects""", flagSourcePos(Abstract))
+      ctx.error(hl("Abstract") + " modifier cannot be used for objects", flagSourcePos(Abstract))
     if (mods.is(Sealed))
-      ctx.error(hl"""$Sealed modifier is redundant for objects""", flagSourcePos(Sealed))
+      ctx.error(hl("Sealed") + " modifier is redundant for objects", flagSourcePos(Sealed))
     // Maybe this should be an error; see https://github.com/scala/bug/issues/11094.
     if (mods.is(Final) && !mods.is(Synthetic))
-      ctx.warning(hl"""$Final modifier is redundant for objects""", flagSourcePos(Final))
+      ctx.warning(hl("Final") + " modifier is redundant for objects", flagSourcePos(Final))
 
     if (mods is Package)
       PackageDef(Ident(moduleName), cpy.ModuleDef(mdef)(nme.PACKAGE, impl).withMods(mods &~ Package) :: Nil)

compiler/src/dotty/tools/dotc/core/Decorators.scala

@@ -184,7 +184,6 @@ object Decorators {
   }
 
   implicit class StringInterpolators(val sc: StringContext) extends AnyVal {
-
     /** General purpose string formatting */
     def i(args: Any*)(implicit ctx: Context): String =
       new StringFormatter(sc).assemble(args)
@@ -200,10 +199,6 @@ object Decorators {
      */
     def ex(args: Any*)(implicit ctx: Context): String =
       explained(implicit ctx => em(args: _*))
-
-    /** Formatter that adds syntax highlighting to all interpolated values */
-    def hl(args: Any*)(implicit ctx: Context): String =
-      new SyntaxFormatter(sc).assemble(args).stripMargin
   }
 
   implicit class ArrayInterpolator[T <: AnyRef](val arr: Array[T]) extends AnyVal {

compiler/src/dotty/tools/dotc/printing/Formatting.scala

@@ -23,7 +23,6 @@ object Formatting {
    *     against accidentally treating an interpolated value as a margin.
    */
   class StringFormatter(protected val sc: StringContext) {
-
     protected def showArg(arg: Any)(implicit ctx: Context): String = arg match {
       case arg: Showable =>
         try arg.show
@@ -207,7 +206,7 @@ object Formatting {
       lazy val maxLen = parts.map(_._1.length).max
       parts.map {
         case (leader, trailer) =>
-          val variable = hl"$leader"
+          val variable = hl(leader)
           s"""$variable${" " * (maxLen - leader.length)} $trailer"""
       }
     }
@@ -277,4 +276,8 @@ object Formatting {
       case _ => (fnd, exp)
     }
   }
+
+  /** Explicit syntax highlighting */
+  def hl(s: String)(implicit ctx: Context): String =
+    SyntaxHighlighting.highlight(s)
 }

compiler/src/dotty/tools/dotc/reporting/MessageRendering.scala

@@ -134,9 +134,9 @@ trait MessageRendering {
   /** Explanation rendered under "Explanation" header */
   def explanation(m: Message)(implicit ctx: Context): String = {
     val sb = new StringBuilder(
-      hl"""|
-           |${Blue("Explanation")}
-           |${Blue("===========")}"""
+      s"""|
+          |${Blue("Explanation").show}
+          |${Blue("===========").show}""".stripMargin
     )
     sb.append(EOL).append(m.explanation)
     if (m.explanation.lastOption != Some(EOL)) sb.append(EOL)