Move SetRootTree right before Pickler

Author: Duhemm

compiler/src/dotty/tools/dotc/Compiler.scala

@@ -39,6 +39,7 @@ class Compiler {
     List(new sbt.ExtractDependencies) :: // Sends information on classes' dependencies to sbt via callbacks
     List(new PostTyper) ::          // Additional checks and cleanups after type checking
     List(new sbt.ExtractAPI) ::     // Sends a representation of the API of classes to sbt via callbacks
+    List(new SetRootTree) ::        // Set the `rootTreeOrProvider` on class symbols
     Nil
 
   /** Phases dealing with TASTY tree pickling and unpickling */
@@ -52,7 +53,6 @@ class Compiler {
     List(new FirstTransform,         // Some transformations to put trees into a canonical form
          new CheckReentrant,         // Internal use only: Check that compiled program has no data races involving global vars
          new ElimPackagePrefixes,    // Eliminate references to package prefixes in Select nodes
-         new SetRootTree,            // Set the `rootTreeOrProvider` on class symbols
          new CookComments) ::        // Cook the comments: expand variables, doc, etc.
     List(new CheckStatic,            // Check restrictions that apply to @static members
          new ElimRepeated,           // Rewrite vararg parameters and arguments

compiler/src/dotty/tools/dotc/Run.scala

@@ -215,7 +215,7 @@ class Run(comp: Compiler, ictx: Context) extends ImplicitRunInfo with Constraint
         def processUnit() = {
           unit.tpdTree = ctx.typer.typedExpr(unit.untpdTree)
           val phase = new transform.SetRootTree()
-          phase.runOn(unit)
+          phase.run
         }
         if (typeCheck)
           if (compiling) finalizeActions += (() => processUnit()) else processUnit()

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

@@ -3,41 +3,34 @@ package dotty.tools.dotc.transform
 import dotty.tools.dotc.CompilationUnit
 import dotty.tools.dotc.ast.tpd
 import dotty.tools.dotc.core.Contexts.Context
-import dotty.tools.dotc.transform.MegaPhase.MiniPhase
+import dotty.tools.dotc.core.Phases.Phase
 
 /** Set the `rootTreeOrProvider` property of class symbols. */
-class SetRootTree extends MiniPhase {
+class SetRootTree extends Phase {
 
   override val phaseName: String = SetRootTree.name
   override def isRunnable(implicit ctx: Context) =
     super.isRunnable && ctx.settings.YretainTrees.value
 
-  def runOn(unit: CompilationUnit)(implicit ctx: Context) = {
-    val runCtx = ctx.fresh.setCompilationUnit(unit)
-    traverser.traverse(unit.tpdTree)(runCtx)
-  }
-
-  override def transformTypeDef(tree: tpd.TypeDef)(implicit ctx: Context): tpd.Tree = {
-    if (tree.symbol.isClass) {
-      val sym = tree.symbol.asClass
-      tpd.sliceTopLevel(ctx.compilationUnit.tpdTree, sym) match {
-        case (pkg: tpd.PackageDef) :: Nil =>
-          sym.rootTreeOrProvider = pkg
-        case _ =>
-          sym.rootTreeOrProvider = tree
-      }
-    }
-    tree
+  override def run(implicit ctx: Context): Unit = {
+    val tree = ctx.compilationUnit.tpdTree
+    traverser.traverse(tree)
   }
 
   private def traverser = new tpd.TreeTraverser {
-    override def traverse(tree: tpd.Tree)(implicit ctx: Context): Unit = tree match {
-      case typeDef: tpd.TypeDef => transformTypeDef(typeDef)
-      case other => traverseChildren(other)
+    override def traverse(tree: tpd.Tree)(implicit ctx: Context): Unit = {
+      if (tree.isInstanceOf[tpd.TypeDef] && tree.symbol.isClass) {
+        val sym = tree.symbol.asClass
+        tpd.sliceTopLevel(ctx.compilationUnit.tpdTree, sym) match {
+          case (pkg: tpd.PackageDef) :: Nil =>
+            sym.rootTreeOrProvider = pkg
+          case _ =>
+            sym.rootTreeOrProvider = tree
+        }
+      }
+      traverseChildren(tree)
     }
   }
-
-
 }
 
 object SetRootTree {