navigation between fields and accessors

This works around SI-5736 that's been deemed too risky to be fixed in 2.10.0.
A reflection newbie will be unlikely to acquire a field symbol from its name,
but the `accessed` method provides an easy way to navigate to it from a getter.

3 files changed, 15 insertions, 1 deletions

diff --git a/src/reflect/scala/reflect/api/Mirrors.scala b/src/reflect/scala/reflect/api/Mirrors.scala
index 27176a2a2d..fe4348d568 100644
--- a/src/reflect/scala/reflect/api/Mirrors.scala
+++ b/src/reflect/scala/reflect/api/Mirrors.scala
@@ -34,7 +34,7 @@ trait Mirrors { self: Universe =>
      *  that can be used to get and, if appropriate, set the value of the field.
      *
      *  To get a field symbol by the name of the field you would like to reflect,
-     *  use `<this mirror>.symbol.typeSignature.member(newTermName(<name of the field>)).asTermSymbol`.
+     *  use `<this mirror>.symbol.typeSignature.member(newTermName(<name of the field>)).asTermSymbol.accessed`.
      *  For further information about member lookup refer to `Symbol.typeSignature`.
      *
      *  The input symbol can be either private or non-private (Scala reflection transparently deals with visibility).
diff --git a/src/reflect/scala/reflect/api/Symbols.scala b/src/reflect/scala/reflect/api/Symbols.scala
index 7a5db4a3f5..7ca1d9c7c6 100644
--- a/src/reflect/scala/reflect/api/Symbols.scala
+++ b/src/reflect/scala/reflect/api/Symbols.scala
@@ -185,6 +185,18 @@ trait Symbols extends base.Symbols { self: Universe =>
 
     /** The overloaded alternatives of this symbol */
     def alternatives: List[Symbol]
+
+    /** Backing field for an accessor method, NoSymbol for all other term symbols.
+     */
+    def accessed: Symbol
+
+    /** Getter method for a backing field of a val or a val, NoSymbol for all other term symbols.
+     */
+    def getter: Symbol
+
+    /** Setter method for a backing field of a val or a val, NoSymbol for all other term symbols.
+     */
+    def setter: Symbol
   }
 
   /** The API of type symbols */
diff --git a/src/reflect/scala/reflect/internal/Symbols.scala b/src/reflect/scala/reflect/internal/Symbols.scala
index 05ead8d1ac..8cf20ba062 100644
--- a/src/reflect/scala/reflect/internal/Symbols.scala
+++ b/src/reflect/scala/reflect/internal/Symbols.scala
@@ -84,6 +84,8 @@ trait Symbols extends api.Symbols { self: SymbolTable =>
     def getAnnotations: List[AnnotationInfo] = { initialize; annotations }
     def setAnnotations(annots: AnnotationInfo*): this.type = { setAnnotations(annots.toList); this }
 
+    def getter: Symbol = getter(owner)
+    def setter: Symbol = setter(owner)
   }
 
   /** The class for all symbols */