fix: don't use color codes for pattern match code action

Author: kasiaMarek

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

@@ -15,6 +15,8 @@ import printing.Formatting
 import ErrorMessageID.*
 import ast.Trees
 import config.{Feature, ScalaVersion}
+import transform.patmat.Space
+import transform.patmat.SpaceEngine
 import typer.ErrorReporting.{err, matchReductionAddendum, substitutableTypeSymbolsInScope}
 import typer.ProtoTypes.{ViewProto, SelectionProto, FunProto}
 import typer.Implicits.*
@@ -856,12 +858,13 @@ extends Message(LossyWideningConstantConversionID):
                 |Write `.to$targetType` instead."""
   def explain(using Context) = ""
 
-class PatternMatchExhaustivity(uncoveredCases: Seq[String], tree: untpd.Match)(using Context)
+class PatternMatchExhaustivity(uncoveredCases: Seq[Space], tree: untpd.Match)(using Context)
 extends Message(PatternMatchExhaustivityID) {
   def kind = MessageKind.PatternMatchExhaustivity
 
   private val hasMore = uncoveredCases.lengthCompare(6) > 0
-  val uncovered = uncoveredCases.take(6).mkString(", ")
+  val uncovered = uncoveredCases.take(6).map(SpaceEngine.display(_)).mkString(", ")
+  private val casesWithoutColor = uncoveredCases.map(SpaceEngine.display(_, withoutColors = true))
 
   def msg(using Context) =
     val addendum = if hasMore then "(More unmatched cases are elided)" else ""
@@ -889,12 +892,12 @@ extends Message(PatternMatchExhaustivityID) {
     val pathes = List(
       ActionPatch(
         srcPos = endPos,
-        replacement = uncoveredCases.map(c => indent(s"case $c => ???", startColumn))
+        replacement = casesWithoutColor.map(c => indent(s"case $c => ???", startColumn))
           .mkString("\n", "\n", "")
       ),
     )
     List(
-      CodeAction(title = s"Insert missing cases (${uncoveredCases.size})",
+      CodeAction(title = s"Insert missing cases (${casesWithoutColor.size})",
         description = None,
         patches = pathes
       )

compiler/src/dotty/tools/dotc/transform/patmat/Space.scala

@@ -721,7 +721,11 @@ object SpaceEngine {
   }
 
   /** Display spaces.  Used for printing uncovered spaces in the in-exhaustive error message. */
-  def display(s: Space)(using Context): String = inContext(ctx.fresh.setPrinterFn(LocalPrinter(_))) {
+  def display(s: Space, withoutColors: Boolean = false)(using Context): String = inContext{
+    val newCtx = ctx.fresh.setPrinterFn(LocalPrinter(_))
+    if withoutColors then newCtx.withoutColors
+    else newCtx
+  } {
     def params(tp: Type): List[Type] = tp.classSymbol.primaryConstructor.info.firstParamTypes
 
     /** does the companion object of the given symbol have custom unapply */
@@ -840,7 +844,7 @@ object SpaceEngine {
 
     if uncovered.nonEmpty then
       val deduped = dedup(uncovered)
-      report.warning(PatternMatchExhaustivity(deduped.map(display), m), m.selector)
+      report.warning(PatternMatchExhaustivity(deduped, m), m.selector)
   }
 
   private def reachabilityCheckable(sel: Tree)(using Context): Boolean =
@@ -903,7 +907,7 @@ object SpaceEngine {
   def checkMatch(m: Match)(using Context): Unit =
     checkMatchExhaustivityOnly(m)
     if reachabilityCheckable(m.selector) then checkReachability(m)
-  
+
   def checkMatchExhaustivityOnly(m: Match)(using Context): Unit =
     if exhaustivityCheckable(m.selector) then checkExhaustivity(m)
 }