WIP on reading binds without changing the format.

Instead of pickling binds multiple times, I use Term\Type-RefDirrect
This works.

But it is still tricky to figure out if bind defines a type or a term.

Author: DarkDimius

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

@@ -153,16 +153,17 @@ class TreePickler(pickler: TastyPickler) {
         pickleName(sym.fullName)
       }
       else if (tpe.prefix == NoPrefix)
-        if (sym is Flags.BindDefinedType) {
-          registerDef(sym)
-          writeByte(BIND)
-          withLength {
-            pickleName(sym.name)
-            pickleType(sym.info)
-            pickleDirectRef()
-          }
-        }
-        else pickleDirectRef()
+//        if (sym is Flags.BindDefinedType) {
+//          registerDef(sym)
+//          writeByte(BIND)
+//          withLength {
+//            pickleName(sym.name)
+//            pickleType(sym.info)
+//            pickleDirectRef()
+//          }
+//        }
+//        else
+          pickleDirectRef()
       else if (isLocallyDefined(sym)) {
         writeByte(if (tpe.isType) TYPEREFsymbol else TERMREFsymbol)
         pickleSymRef(sym); pickleType(tpe.prefix)

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

@@ -109,7 +109,7 @@ class TreeUnpickler(reader: TastyReader, nameAtRef: NameRef => TermName, posUnpi
       val start = currentAddr
       val tag = readByte()
       tag match {
-        case VALDEF | DEFDEF | TYPEDEF | TYPEPARAM | PARAM | TEMPLATE =>
+        case VALDEF | DEFDEF | TYPEDEF | TYPEPARAM | PARAM | TEMPLATE | BIND =>
           val end = readEnd()
           for (i <- 0 until numRefs(tag)) readNat()
           if (tag == TEMPLATE) scanTrees(buf, end, MemberDefsOnly)
@@ -254,6 +254,7 @@ class TreeUnpickler(reader: TastyReader, nameAtRef: NameRef => TermName, posUnpi
             case TYPEARGtype =>
               TypeArgRef(readType(), readType().asInstanceOf[TypeRef], readNat())
             case BIND =>
+              ctx.error("Should never happen, should be in tree")
               val sym = ctx.newSymbol(ctx.owner, readName().toTypeName, BindDefinedType, readType())
               registerSym(start, sym)
               if (currentAddr != end) readType()
@@ -412,6 +413,15 @@ class TreeUnpickler(reader: TastyReader, nameAtRef: NameRef => TermName, posUnpi
         val localDummy = ctx.newLocalDummy(ctx.owner)
         registerSym(currentAddr, localDummy)
         localDummy
+      case BIND =>
+        val start = currentAddr
+        val tag = readByte()
+        val end = readEnd()
+        val name = readName()
+        val info = new Completer(ctx.owner, subReader(start, end))
+        val sym = ctx.newSymbol(ctx.owner, name, EmptyFlags, info)
+        registerSym(start, sym)
+        sym
       case tag =>
         throw new Error(s"illegal createSymbol at $currentAddr, tag = $tag")
     }
@@ -982,9 +992,9 @@ class TreeUnpickler(reader: TastyReader, nameAtRef: NameRef => TermName, posUnpi
               SeqLiteral(until(end)(readTerm()), elemtpt)
             case BIND =>
               val name = readName()
-              val info = readType()
-              val sym = ctx.newSymbol(ctx.owner, name, EmptyFlags, info)
-              registerSym(start, sym)
+              val sym = symbolAt(start).asTerm
+              skipTree()// skip type
+              // symbol has to be created before reading the type, as the type may refer to the symbpl
               Bind(sym, readTerm())
             case ALTERNATIVE =>
               Alternative(until(end)(readTerm()))
@@ -1042,7 +1052,15 @@ class TreeUnpickler(reader: TastyReader, nameAtRef: NameRef => TermName, posUnpi
     }
 
     def readTpt()(implicit ctx: Context) =
-      if (isTypeTreeTag(nextUnsharedTag)) readTerm()
+      if (isTypeTreeTag(nextUnsharedTag)) {
+        val isShared = nextByte == SHARED
+        val term = readTerm()
+        term match {
+          case a: DefTree if isShared =>
+            TypeTree(a.namedType)
+          case _ => term
+        }
+      }
       else {
         val start = currentAddr
         val tp = readType()

tests/link/on-custom-lib/map2.scala

@@ -1,4 +1,4 @@
-import strawman.collection._
+//import strawman.collection._
 
 object Test {
   def main(args: Array[String]): Unit = {