1 files changed, 36 insertions, 0 deletions
diff --git a/src/compiler/scala/reflect/macros/contexts/Enclosures.scala b/src/compiler/scala/reflect/macros/contexts/Enclosures.scala
new file mode 100644
index 0000000000..bb88c8d5e1
--- /dev/null
+++ b/src/compiler/scala/reflect/macros/contexts/Enclosures.scala
@@ -0,0 +1,36 @@
+package scala.reflect.macros
+package contexts
+
+import scala.reflect.{ClassTag, classTag}
+
+trait Enclosures {
+  self: Context =>
+
+  import universe._
+
+  type MacroRole = analyzer.MacroRole
+  def APPLY_ROLE = analyzer.APPLY_ROLE
+  def macroRole: MacroRole
+
+  private lazy val site       = callsiteTyper.context
+  private lazy val enclTrees  = site.enclosingContextChain map (_.tree)
+  private lazy val enclPoses  = enclosingMacros map (_.macroApplication.pos) filterNot (_ eq NoPosition)
+
+  private def lenientEnclosure[T <: Tree : ClassTag]: Tree = enclTrees collectFirst { case x: T => x } getOrElse EmptyTree
+  private def strictEnclosure[T <: Tree : ClassTag]: T = enclTrees collectFirst { case x: T => x } getOrElse (throw new EnclosureException(classTag[T].runtimeClass, enclTrees))
+
+  // vals are eager to simplify debugging
+  // after all we wouldn't save that much time by making them lazy
+  val macroApplication: Tree                      = expandee
+  def enclosingPackage: PackageDef                = strictEnclosure[PackageDef]
+  val enclosingClass: Tree                        = lenientEnclosure[ImplDef]
+  def enclosingImpl: ImplDef                      = strictEnclosure[ImplDef]
+  def enclosingTemplate: Template                 = strictEnclosure[Template]
+  val enclosingImplicits: List[ImplicitCandidate] = site.openImplicits.map(_.toImplicitCandidate)
+  val enclosingMacros: List[Context]              = this :: universe.analyzer.openMacros // include self
+  val enclosingMethod: Tree                       = lenientEnclosure[DefDef]
+  def enclosingDef: DefDef                        = strictEnclosure[DefDef]
+  val enclosingPosition: Position                 = if (enclPoses.isEmpty) NoPosition else enclPoses.head.pos
+  val enclosingUnit: CompilationUnit              = universe.currentRun.currentUnit
+  val enclosingRun: Run                           = universe.currentRun
+}