Fix printing of reach capabilities

Author: odersky

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

@@ -416,10 +416,10 @@ class PlainPrinter(_ctx: Context) extends Printer {
     homogenize(tp) match
       case tp: TermRef if tp.symbol == defn.captureRoot => Str("cap")
       case tp: SingletonType => toTextRef(tp)
-      case ReachCapability(tp1) => toTextRef(tp1) ~ "*"
-      case MaybeCapability(tp1) => toTextRef(tp1) ~ "?"
       case tp: (TypeRef | TypeParamRef) => toText(tp) ~ "^"
-      case _ => toText(tp)
+      case tp: AnnotatedType if tp.isReach => toTextCaptureRef(tp.stripReach) ~ "*"
+      case tp: AnnotatedType if tp.isMaybe => toTextCaptureRef(tp.stripMaybe) ~ "?"
+      case tp => toText(tp)
 
   protected def isOmittablePrefix(sym: Symbol): Boolean =
     defn.unqualifiedOwnerTypes.exists(_.symbol == sym) || isEmptyPrefix(sym)

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

@@ -330,6 +330,8 @@ class RefinedPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
         "?" ~ (("(ignored: " ~ toText(ignored) ~ ")") provided printDebug)
       case tp @ PolyProto(targs, resType) =>
         "[applied to [" ~ toTextGlobal(targs, ", ") ~ "] returning " ~ toText(resType)
+      case tp: AnnotatedType if tp.isReach || tp.isMaybe =>
+        toTextCaptureRef(tp)
       case _ =>
         super.toText(tp)
     }

tests/neg-custom-args/captures/reaches2.check

@@ -1,10 +1,10 @@
 -- Error: tests/neg-custom-args/captures/reaches2.scala:8:10 -----------------------------------------------------------
 8 |  ps.map((x, y) => compose1(x, y)) // error // error
   |          ^
-  |reference (ps : List[(box A => A, box A => A)]) @reachCapability is not included in the allowed capture set {}
+  |reference ps* is not included in the allowed capture set {}
   |of an enclosing function literal with expected type ((box A ->{ps*} A, box A ->{ps*} A)) -> box (x$0: A^?) ->? (ex$15: caps.Exists) -> A^?
 -- Error: tests/neg-custom-args/captures/reaches2.scala:8:13 -----------------------------------------------------------
 8 |  ps.map((x, y) => compose1(x, y)) // error // error
   |             ^
-  |reference (ps : List[(box A => A, box A => A)]) @reachCapability is not included in the allowed capture set {}
+  |reference ps* is not included in the allowed capture set {}
   |of an enclosing function literal with expected type ((box A ->{ps*} A, box A ->{ps*} A)) -> box (x$0: A^?) ->? (ex$15: caps.Exists) -> A^?