1 files changed, 53 insertions, 0 deletions
diff --git a/compiler/src/dotty/tools/dotc/core/tasty/DottyUnpickler.scala b/compiler/src/dotty/tools/dotc/core/tasty/DottyUnpickler.scala
new file mode 100644
index 000000000..2c93819d5
--- /dev/null
+++ b/compiler/src/dotty/tools/dotc/core/tasty/DottyUnpickler.scala
@@ -0,0 +1,53 @@
+package dotty.tools
+package dotc
+package core
+package tasty
+
+import Contexts._, SymDenotations._, Symbols._
+import dotty.tools.dotc.ast.tpd
+import TastyUnpickler._, TastyBuffer._
+import util.Positions._
+import util.{SourceFile, NoSource}
+import Annotations.Annotation
+import core.Mode
+import classfile.ClassfileParser
+
+object DottyUnpickler {
+
+  /** Exception thrown if classfile is corrupted */
+  class BadSignature(msg: String) extends RuntimeException(msg)
+
+  class TreeSectionUnpickler(posUnpickler: Option[PositionUnpickler])
+  extends SectionUnpickler[TreeUnpickler]("ASTs") {
+    def unpickle(reader: TastyReader, tastyName: TastyName.Table) =
+      new TreeUnpickler(reader, tastyName, posUnpickler)
+  }
+
+  class PositionsSectionUnpickler extends SectionUnpickler[PositionUnpickler]("Positions") {
+    def unpickle(reader: TastyReader, tastyName: TastyName.Table) =
+      new PositionUnpickler(reader)
+  }
+}
+
+/** A class for unpickling Tasty trees and symbols.
+ *  @param bytes         the bytearray containing the Tasty file from which we unpickle
+ */
+class DottyUnpickler(bytes: Array[Byte]) extends ClassfileParser.Embedded {
+  import tpd._
+  import DottyUnpickler._
+
+  val unpickler = new TastyUnpickler(bytes)
+  private val posUnpicklerOpt = unpickler.unpickle(new PositionsSectionUnpickler)
+  private val treeUnpickler = unpickler.unpickle(new TreeSectionUnpickler(posUnpicklerOpt)).get
+
+  /** 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])(implicit ctx: Context): Unit =
+    treeUnpickler.enterTopLevel(roots)
+
+  /** The unpickled trees, and the source file they come from. */
+  def body(implicit ctx: Context): List[Tree] = {
+    treeUnpickler.unpickle()
+  }
+}