Infere if this TASTY tree is top level or a term

Author: nicolasstucki

compiler/src/dotty/tools/dotc/core/classfile/ClassfileParser.scala

@@ -758,7 +758,7 @@ class ClassfileParser(
 
       def unpickleTASTY(bytes: Array[Byte]): Some[Embedded]  = {
         val unpickler = new tasty.DottyUnpickler(bytes)
-        unpickler.enter(roots = Set(classRoot, moduleRoot, moduleRoot.sourceModule), isTopLevel = true)
+        unpickler.enter(roots = Set(classRoot, moduleRoot, moduleRoot.sourceModule))
         Some(unpickler)
       }
 

compiler/src/dotty/tools/dotc/core/quoted/PickledQuotes.scala

@@ -105,7 +105,7 @@ object PickledQuotes {
     }
 
     val unpickler = new TastyUnpickler(bytes, splices)
-    unpickler.enter(Set(ctx.owner), isTopLevel = false)
+    unpickler.enter(Set(ctx.owner))
     val tree = unpickler.tree
 
     if (pickling ne noPrinter)

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

@@ -43,8 +43,8 @@ class DottyUnpickler(bytes: Array[Byte]) extends ClassfileParser.Embedded with t
   /** Enter all toplevel classes and objects into their scopes
    *  @param roots          a set of SymDenotations that should be overwritten by unpickling
    */
-  def enter(roots: Set[SymDenotation], isTopLevel: Boolean)(implicit ctx: Context): Unit =
-    treeUnpickler.enter(roots, isTopLevel)
+  def enter(roots: Set[SymDenotation])(implicit ctx: Context): Unit =
+    treeUnpickler.enter(roots)
 
   def unpickleTypeTree()(implicit ctx: Context): Tree =
     treeUnpickler.unpickleTypeTree()

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

@@ -52,9 +52,6 @@ class TreeUnpickler(reader: TastyReader,
    */
   private val typeAtAddr = new mutable.HashMap[Addr, Type]
 
-  /** If the Tasty corresponds to a top level tree. `flase` is used used for quotes */
-  private[this] var isTopLevel: Boolean = true
-
   /** The root symbol denotation which are defined by the Tasty file associated with this
    *  TreeUnpickler. Set by `enterTopLevel`.
    */
@@ -74,12 +71,11 @@ class TreeUnpickler(reader: TastyReader,
   /** Enter all toplevel classes and objects into their scopes
    *  @param roots          a set of SymDenotations that should be overwritten by unpickling
    */
-  def enter(roots: Set[SymDenotation], isTopLevel: Boolean)(implicit ctx: Context): Unit = {
-    this.isTopLevel = isTopLevel
+  def enter(roots: Set[SymDenotation])(implicit ctx: Context): Unit = {
     this.roots = roots
     val rdr = new TreeReader(reader).fork
     ownerTree = new OwnerTree(NoAddr, 0, rdr.fork, reader.endAddr)
-    if (isTopLevel)
+    if (rdr.isTopLevel)
       rdr.indexStats(reader.endAddr)
   }
 
@@ -94,7 +90,7 @@ class TreeUnpickler(reader: TastyReader,
   def unpickle()(implicit ctx: Context): List[Tree] = {
     assert(roots != null, "unpickle without previous enterTopLevel")
     val rdr = new TreeReader(reader)
-    if (isTopLevel) rdr.readTopLevel()
+    if (rdr.isTopLevel) rdr.readTopLevel()
     else rdr.readTerm() :: Nil
   }
 
@@ -863,15 +859,15 @@ class TreeUnpickler(reader: TastyReader,
     }
 
     def skipToplevel()(implicit ctx: Context): Unit= {
-      if (!isAtEnd)
-        nextByte match {
-          case IMPORT | PACKAGE =>
-            skipTree()
-            skipToplevel()
-          case _ =>
-        }
+      if (!isAtEnd && isTopLevel) {
+        skipTree()
+        skipToplevel()
+      }
     }
 
+    def isTopLevel(implicit ctx: Context): Boolean =
+      nextByte == IMPORT || nextByte == PACKAGE
+
     def readTopLevel()(implicit ctx: Context): List[Tree] = {
       @tailrec def read(acc: ListBuffer[Tree]): List[Tree] = nextByte match {
         case IMPORT | PACKAGE =>

compiler/src/dotty/tools/dotc/transform/Pickler.scala

@@ -94,7 +94,7 @@ class Pickler extends Phase {
     val unpicklers =
       for ((cls, pickler) <- picklers) yield {
         val unpickler = new DottyUnpickler(pickler.assembleParts())
-        unpickler.enter(roots = Set(), isTopLevel = true)
+        unpickler.enter(roots = Set())
         cls -> unpickler
       }
     pickling.println("************* entered toplevel ***********")