new annotation targets for companion classes/objects/factory methods.

5 files changed, 55 insertions, 5 deletions

diff --git a/src/compiler/scala/reflect/internal/Definitions.scala b/src/compiler/scala/reflect/internal/Definitions.scala
index 6ef6751720..dc8f59b0af 100644
--- a/src/compiler/scala/reflect/internal/Definitions.scala
+++ b/src/compiler/scala/reflect/internal/Definitions.scala
@@ -905,7 +905,9 @@ trait Definitions extends reflect.api.StandardDefinitions {
     lazy val GetterTargetClass          = getMetaAnnotation("getter")
     lazy val ParamTargetClass           = getMetaAnnotation("param")
     lazy val SetterTargetClass          = getMetaAnnotation("setter")
-    // TODO: module, moduleClass? package, packageObject?
+    lazy val ClassTargetClass           = getMetaAnnotation("companionClass")
+    lazy val ObjectTargetClass          = getMetaAnnotation("companionObject")
+    lazy val MethodTargetClass          = getMetaAnnotation("companionMethod")    // TODO: module, moduleClass? package, packageObject?
 
     private def getMetaAnnotation(name: String) = getRequiredClass("scala.annotation.meta." + name)
     def isMetaAnnotation(sym: Symbol): Boolean = metaAnnotations(sym) || (
diff --git a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
index ff0bdf7580..4a05b28867 100644
--- a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
@@ -832,7 +832,7 @@ trait ContextErrors {
       implicit val context0 = context
 
       object SymValidateErrors extends Enumeration {
-        val ImplicitConstr, ImplicitNotTerm, ImplicitTopObject,
+        val ImplicitConstr, ImplicitNotTermOrClass, ImplicitAtToplevel,
           OverrideClass, SealedNonClass, AbstractNonClass,
           OverrideConstr, AbstractOverride, LazyAndEarlyInit,
           ByNameParameter, AbstractVar = Value
@@ -898,10 +898,10 @@ trait ContextErrors {
           case ImplicitConstr =>
             "`implicit' modifier not allowed for constructors"
 
-          case ImplicitNotTerm =>
-            "`implicit' modifier can be used only for values, variables and methods"
+          case ImplicitNotTermOrClass =>
+            "`implicit' modifier can be used only for values, variables, methods and classes"
 
-          case ImplicitTopObject =>
+          case ImplicitAtToplevel =>
             "`implicit' modifier cannot be used for top-level objects"
 
           case OverrideClass =>
diff --git a/src/library/scala/annotation/meta/companionClass.scala b/src/library/scala/annotation/meta/companionClass.scala
new file mode 100644
index 0000000000..8e53f6caf9
--- /dev/null
+++ b/src/library/scala/annotation/meta/companionClass.scala
@@ -0,0 +1,17 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2002-2011, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+package scala.annotation.meta
+
+/**
+ * When defining an implicit class, the Scala compiler creates an implicit
+ * conversion method for it. Annotations `@companionClass` and `@companionMethod`
+ * control where an annotation on the implicit class will go. By default, annotations
+ * on an implicit class end up only on the class.
+ * 
+ */
+final class companionClass extends annotation.StaticAnnotation
diff --git a/src/library/scala/annotation/meta/companionMethod.scala b/src/library/scala/annotation/meta/companionMethod.scala
new file mode 100644
index 0000000000..379c4f3385
--- /dev/null
+++ b/src/library/scala/annotation/meta/companionMethod.scala
@@ -0,0 +1,17 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2002-2011, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+package scala.annotation.meta
+
+/**
+ * When defining an implicit class, the Scala compiler creates an implicit
+ * conversion method for it. Annotations `@companionClass` and `@companionMethod`
+ * control where an annotation on the implicit class will go. By default, annotations
+ * on an implicit class end up only on the class.
+ * 
+ */
+final class companionMethod extends annotation.StaticAnnotation
diff --git a/src/library/scala/annotation/meta/companionObject.scala b/src/library/scala/annotation/meta/companionObject.scala
new file mode 100644
index 0000000000..d329df5c42
--- /dev/null
+++ b/src/library/scala/annotation/meta/companionObject.scala
@@ -0,0 +1,14 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2002-2011, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+package scala.annotation.meta
+
+/**
+ * Currently unused; intended as an annotation target for classes such as case classes
+ * that automatically generate a companion object
+ */
+final class companionObject extends annotation.StaticAnnotation