refactors handling of macros in repl

Macros now have a dedicated member handler, so that the logic of their
processing doesn't get mixed up with vanilla DefHandler.

I've also factored out an abstract MacroHandler to provides a basis
to build the upcoming type macro handler upon.

3 files changed, 27 insertions, 15 deletions

diff --git a/src/compiler/scala/tools/nsc/interpreter/MemberHandlers.scala b/src/compiler/scala/tools/nsc/interpreter/MemberHandlers.scala
index 5b0705a39e..84a47311e2 100644
--- a/src/compiler/scala/tools/nsc/interpreter/MemberHandlers.scala
+++ b/src/compiler/scala/tools/nsc/interpreter/MemberHandlers.scala
@@ -48,16 +48,19 @@ trait MemberHandlers {
     }
   }
 
+  private def isTermMacro(ddef: DefDef): Boolean = ddef.mods.isMacro
+
   def chooseHandler(member: Tree): MemberHandler = member match {
-    case member: DefDef        => new DefHandler(member)
-    case member: ValDef        => new ValHandler(member)
-    case member: ModuleDef     => new ModuleHandler(member)
-    case member: ClassDef      => new ClassHandler(member)
-    case member: TypeDef       => new TypeAliasHandler(member)
-    case member: Assign        => new AssignHandler(member)
-    case member: Import        => new ImportHandler(member)
-    case DocDef(_, documented) => chooseHandler(documented)
-    case member                => new GenericHandler(member)
+    case member: DefDef if isTermMacro(member) => new TermMacroHandler(member)
+    case member: DefDef                        => new DefHandler(member)
+    case member: ValDef                        => new ValHandler(member)
+    case member: ModuleDef                     => new ModuleHandler(member)
+    case member: ClassDef                      => new ClassHandler(member)
+    case member: TypeDef                       => new TypeAliasHandler(member)
+    case member: Assign                        => new AssignHandler(member)
+    case member: Import                        => new ImportHandler(member)
+    case DocDef(_, documented)                 => chooseHandler(documented)
+    case member                                => new GenericHandler(member)
   }
 
   sealed abstract class MemberDefHandler(override val member: MemberDef) extends MemberHandler(member) {
@@ -122,14 +125,23 @@ trait MemberHandlers {
   }
 
   class DefHandler(member: DefDef) extends MemberDefHandler(member) {
-    private def vparamss = member.vparamss
-    private def isMacro = member.symbol hasFlag MACRO
-    // true if not a macro and 0-arity
-    override def definesValue = !isMacro && flattensToEmpty(vparamss)
+    override def definesValue = flattensToEmpty(member.vparamss) // true if 0-arity
     override def resultExtractionCode(req: Request) =
       if (mods.isPublic) codegenln(name, ": ", req.typeOf(name)) else ""
   }
 
+  abstract class MacroHandler(member: DefDef) extends MemberDefHandler(member) {
+    override def definesValue = false
+    override def definesTerm: Option[TermName] = Some(name.toTermName)
+    override def definesType: Option[TypeName] = None
+    override def resultExtractionCode(req: Request) = if (mods.isPublic) codegenln(notification(req)) else ""
+    def notification(req: Request): String
+  }
+
+  class TermMacroHandler(member: DefDef) extends MacroHandler(member) {
+    def notification(req: Request) = s"defined term macro $name: ${req.typeOf(name)}"
+  }
+
   class AssignHandler(member: Assign) extends MemberHandler(member) {
     val Assign(lhs, rhs) = member
     override lazy val name = newTermName(freshInternalVarName())
diff --git a/test/files/run/macro-repl-dontexpand.check b/test/files/run/macro-repl-dontexpand.check
index 628a9146c4..99b70ea3dc 100644
--- a/test/files/run/macro-repl-dontexpand.check
+++ b/test/files/run/macro-repl-dontexpand.check
@@ -7,6 +7,6 @@ scala> def bar(c: scala.reflect.macros.Context) = ???
 bar: (c: scala.reflect.macros.Context)Nothing
 
 scala> def foo = macro bar
-foo: Any
+defined term macro foo: Any
 
 scala> 
diff --git a/test/files/run/t6381.check b/test/files/run/t6381.check
index b51cfd0398..5070b67e46 100644
--- a/test/files/run/t6381.check
+++ b/test/files/run/t6381.check
@@ -9,7 +9,7 @@ scala> def pos_impl(c: reflect.macros.Context): c.Expr[String] =
 pos_impl: (c: scala.reflect.macros.Context)c.Expr[String]
 
 scala> def pos = macro pos_impl
-pos: String
+defined term macro pos: String
 
 scala> pos
 res0: String = class scala.reflect.internal.util.RangePosition