New flag Exported for export forwarders

Author: odersky

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

@@ -394,6 +394,9 @@ object Flags {
   /** Symbol is an enum class or enum case (if used with case) */
   final val Enum: FlagSet = commonFlag(40, "<enum>")
 
+  /** An export forwarder */
+  final val Exported: FlagSet = commonFlag(41, "exported")
+
   /** Labeled with `erased` modifier (erased value)  */
   final val Erased: FlagSet = termFlag(42, "erased")
 

compiler/src/dotty/tools/dotc/core/tasty/TastyFormat.scala

@@ -208,6 +208,7 @@ Standard-Section: "ASTs" TopLevelStat*
                   EXTENSION                                                        -- An extension method
                   GIVEN                                                            -- A new style implicit parameter, introduced with `given`
                   PARAMsetter                                                      -- The setter part `x_=` of a var parameter `x` which itself is pickled as a PARAM
+                  EXPORTED                                                         -- An export forwarder
                   Annotation
 
   Annotation    = ANNOTATION     Length tycon_Type fullAnnotation_Term             -- An annotation, given (class) type of constructor, and full application tree
@@ -329,6 +330,7 @@ object TastyFormat {
   final val GIVEN = 37
   final val IMPLIED = 38
   final val PARAMsetter = 39
+  final val EXPORTED = 40
 
   // Cat. 2:    tag Nat
 
@@ -457,7 +459,7 @@ object TastyFormat {
 
   /** Useful for debugging */
   def isLegalTag(tag: Int): Boolean =
-    firstSimpleTreeTag <= tag && tag <= PARAMsetter ||
+    firstSimpleTreeTag <= tag && tag <= EXPORTED ||
     firstNatTreeTag <= tag && tag <= SYMBOLconst ||
     firstASTTreeTag <= tag && tag <= SINGLETONtpt ||
     firstNatASTTreeTag <= tag && tag <= NAMEDARG ||
@@ -500,6 +502,7 @@ object TastyFormat {
        | EXTENSION
        | GIVEN
        | PARAMsetter
+       | EXPORTED
        | ANNOTATION
        | PRIVATEqualified
        | PROTECTEDqualified => true
@@ -560,6 +563,7 @@ object TastyFormat {
     case EXTENSION => "EXTENSION"
     case GIVEN => "GIVEN"
     case PARAMsetter => "PARAMsetter"
+    case EXPORTED => "EXPORTED"
 
     case SHAREDterm => "SHAREDterm"
     case SHAREDtype => "SHAREDtype"

compiler/src/dotty/tools/dotc/core/tasty/TreePickler.scala

@@ -656,6 +656,7 @@ class TreePickler(pickler: TastyPickler) {
       if (flags is Extension) writeByte(EXTENSION)
       if (flags is Given) writeByte(GIVEN)
       if (flags is ParamAccessor) writeByte(PARAMsetter)
+      if (flags is Exported) writeByte(EXPORTED)
       assert(!(flags is Label))
     } else {
       if (flags is Sealed) writeByte(SEALED)

compiler/src/dotty/tools/dotc/core/tasty/TreeUnpickler.scala

@@ -632,8 +632,8 @@ class TreeUnpickler(reader: TastyReader,
           case STABLE => addFlag(StableRealizable)
           case EXTENSION => addFlag(Extension)
           case GIVEN => addFlag(Given)
-          case PARAMsetter =>
-            addFlag(ParamAccessor)
+          case PARAMsetter => addFlag(ParamAccessor)
+          case EXPORTED => addFlag(Exported)
           case PRIVATEqualified =>
             readByte()
             privateWithin = readWithin(ctx)

compiler/src/dotty/tools/dotc/typer/Namer.scala

@@ -981,14 +981,14 @@ class Namer { typer: Typer =>
               if (mbr.isType)
                 ctx.newSymbol(
                   cls, alias.toTypeName,
-                  Final,
+                  Exported | Final,
                   fwdInfo(path.tpe.select(mbr.symbol), mbr.info),
                   coord = span)
               else {
                 val maybeStable = if (mbr.symbol.isStableMember) StableRealizable else EmptyFlags
                 ctx.newSymbol(
                   cls, alias,
-                  Method | Final | maybeStable | mbr.symbol.flags & ImplicitOrImplied,
+                  Exported | Method | Final | maybeStable | mbr.symbol.flags & ImplicitOrImplied,
                   mbr.info.ensureMethodic,
                   coord = span)
               }