5 files changed, 12 insertions, 3 deletions
diff --git a/src/dotty/tools/dotc/core/Contexts.scala b/src/dotty/tools/dotc/core/Contexts.scala
index af8bd6e91..6ff6e148d 100644
--- a/src/dotty/tools/dotc/core/Contexts.scala
+++ b/src/dotty/tools/dotc/core/Contexts.scala
@@ -293,8 +293,7 @@ object Contexts {
     /** The standard fresh name creator */
     val freshNames = new FreshNameCreator.Default
 
-    def freshName(): String = freshNames.newName()
-    def freshName(prefix: String): String = freshNames.newName(prefix)
+    def freshName(prefix: String = ""): String = freshNames.newName(prefix)
     def freshName(prefix: Name): String = freshName(prefix.toString)
 
     /** The loader that loads the members of _root_ */
diff --git a/src/dotty/tools/dotc/core/Decorators.scala b/src/dotty/tools/dotc/core/Decorators.scala
index 031974dfd..094aa7b4a 100644
--- a/src/dotty/tools/dotc/core/Decorators.scala
+++ b/src/dotty/tools/dotc/core/Decorators.scala
@@ -70,6 +70,10 @@ object Decorators {
       }
   }
 
+  implicit class ListOfListDecorator[T](val xss: List[List[T]]) extends AnyVal {
+    def nestedMap[U](f: T => U): List[List[U]] = xss map (_ map f)
+  }
+
   implicit class TextToString(val text: Text) extends AnyVal {
     def show(implicit ctx: Context) = text.mkString(ctx.settings.pageWidth.value)
   }
diff --git a/src/dotty/tools/dotc/core/StdNames.scala b/src/dotty/tools/dotc/core/StdNames.scala
index ada74c69d..9ae4729f4 100644
--- a/src/dotty/tools/dotc/core/StdNames.scala
+++ b/src/dotty/tools/dotc/core/StdNames.scala
@@ -380,6 +380,7 @@ object StdNames {
     val info: N                 = "info"
     val inlinedEquals: N        = "inlinedEquals"
     val isArray: N              = "isArray"
+    val isDefined: N            = "isDefined"
     val isDefinedAt: N          = "isDefinedAt"
     val isEmpty: N              = "isEmpty"
     val isInstanceOf_ : N       = "isInstanceOf"
diff --git a/src/dotty/tools/dotc/core/SymDenotations.scala b/src/dotty/tools/dotc/core/SymDenotations.scala
index bec55720f..51e03aee7 100644
--- a/src/dotty/tools/dotc/core/SymDenotations.scala
+++ b/src/dotty/tools/dotc/core/SymDenotations.scala
@@ -470,6 +470,11 @@ object SymDenotations {
     final def enclosingClass(implicit ctx: Context): Symbol =
       if (isClass) symbol else owner.enclosingClass
 
+    final def enclosingClassNamed(name: Name)(implicit ctx: Context): Symbol = {
+      val cls = enclosingClass
+      if (cls.name == name) cls else cls.owner.enclosingClassNamed(name)
+    }
+
     /** The top-level class containing this denotation,
      *  except for a toplevel module, where its module class is returned.
      */
diff --git a/src/dotty/tools/dotc/core/Types.scala b/src/dotty/tools/dotc/core/Types.scala
index 1b21567a0..880cb7174 100644
--- a/src/dotty/tools/dotc/core/Types.scala
+++ b/src/dotty/tools/dotc/core/Types.scala
@@ -1556,7 +1556,7 @@ object Types {
 
 
   /** The type of an import clause tree */
-  case class ImportType(expr: SharedTree) extends UncachedGroundType
+  case class ImportType(expr: Tree) extends UncachedGroundType
 
   /** Sentinal for "missing type" */
   case object NoType extends CachedGroundType {