Move compiler and compiler tests to compiler dir

1 files changed, 47 insertions, 0 deletions

diff --git a/compiler/src/dotty/tools/dotc/transform/Flatten.scala b/compiler/src/dotty/tools/dotc/transform/Flatten.scala
new file mode 100644
index 000000000..f0104e715
--- /dev/null
+++ b/compiler/src/dotty/tools/dotc/transform/Flatten.scala
@@ -0,0 +1,47 @@
+package dotty.tools.dotc
+package transform
+
+import core._
+import DenotTransformers.SymTransformer
+import Phases.Phase
+import Contexts.Context
+import Flags._
+import SymDenotations.SymDenotation
+import collection.mutable
+import TreeTransforms.MiniPhaseTransform
+import dotty.tools.dotc.transform.TreeTransforms.TransformerInfo
+
+/** Lift nested classes to toplevel */
+class Flatten extends MiniPhaseTransform with SymTransformer { thisTransform =>
+  import ast.tpd._
+  override def phaseName = "flatten"
+
+  def transformSym(ref: SymDenotation)(implicit ctx: Context) = {
+    if (ref.isClass && !ref.is(Package) && !ref.owner.is(Package)) {
+      ref.copySymDenotation(
+        name = ref.flatName,
+        owner = ref.enclosingPackageClass)
+    }
+    else ref
+  }
+
+  private val liftedDefs = new mutable.ListBuffer[Tree]
+
+  private def liftIfNested(tree: Tree)(implicit ctx: Context, info: TransformerInfo) =
+    if (ctx.owner is Package) tree
+    else {
+      transformFollowing(tree).foreachInThicket(liftedDefs += _)
+      EmptyTree
+    }
+
+  override def transformStats(stats: List[Tree])(implicit ctx: Context, info: TransformerInfo) =
+    if (ctx.owner is Package) {
+      val liftedStats = stats ++ liftedDefs
+      liftedDefs.clear
+      liftedStats
+    }
+    else stats
+
+  override def transformTypeDef(tree: TypeDef)(implicit ctx: Context, info: TransformerInfo) =
+    liftIfNested(tree)
+}