From c64a35895a139c3ed91d39150025bc8864aad732 Mon Sep 17 00:00:00 2001
From: Felix Mulder <felix.mulder@gmail.com>
Date: Fri, 25 Aug 2017 15:36:23 +0200
Subject: [PATCH] Properly strip REPL wrapper object path from nested types

This commit allows the UserFacingPrinter to remove a part of the full
path of the type it is printing. This means that despite types being
deeply nested, they should not leak REPL names
---
 .../dotty/tools/repl/UserFacingPrinter.scala  | 23 +++++++++++++------
 repl/test-resources/repl/i2554                |  9 ++++++++
 2 files changed, 25 insertions(+), 7 deletions(-)
 create mode 100644 repl/test-resources/repl/i2554

diff --git a/repl/src/dotty/tools/repl/UserFacingPrinter.scala b/repl/src/dotty/tools/repl/UserFacingPrinter.scala
index ac2c3f48e5e5..55ec71f633e7 100644
--- a/repl/src/dotty/tools/repl/UserFacingPrinter.scala
+++ b/repl/src/dotty/tools/repl/UserFacingPrinter.scala
@@ -33,13 +33,17 @@ class UserFacingPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
   private lazy val scalaPkg      = defn.ScalaPackageClass
   private lazy val javaLangPkg   = defn.JavaLangPackageVal.moduleClass.asClass
 
-  def wellKnownPkg(pkgSym: Symbol) = pkgSym match {
+  def standardPkg(pkgSym: Symbol) = pkgSym match {
     case `scalaPkg` | `collectionPkg` | `immutablePkg` | `javaLangPkg` => true
-    case pkgSym =>
-      pkgSym.name.toTermName == nme.EMPTY_PACKAGE ||
-      pkgSym.name.isReplWrapperName
+    case _ => false
   }
 
+  def wrappedName(pkgSym: Symbol) =
+    pkgSym.name.toTermName == nme.EMPTY_PACKAGE ||
+    pkgSym.name.isReplWrapperName
+
+  def wellKnownPkg(pkgSym: Symbol) = standardPkg(pkgSym) || wrappedName(pkgSym)
+
   override protected def keyString(sym: Symbol): String = {
     val flags = sym.flags
     if (flags is Package) ""
@@ -48,6 +52,7 @@ class UserFacingPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
     else if (sym.isClass && flags.is(Case)) "case class"
     else if (flags.is(Lazy)) "lazy val"
     else if (flags is Module) "object"
+    else if (sym.isTerm && !flags.is(Param) && flags.is(Implicit)) "implicit val"
     else super.keyString(sym)
   }
 
@@ -86,7 +91,9 @@ class UserFacingPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
     case tp: ConstantType => toText(tp.value)
     case tp: TypeAlias => toText(tp.underlying)
     case ExprType(result) => ":" ~~ toText(result)
-    case TypeBounds(lo, hi) => "_"
+    case TypeBounds(lo, hi) =>
+      { if (lo != defn.NothingType) toText(lo) ~~ ">: _" else Str("_") } ~~
+      { if (hi != defn.AnyType) "<:" ~~ toText(hi) else Text() }
     case tp: TypeRef => tp.info match {
       case TypeAlias(alias) => toText(alias)
       case _ => toText(tp.info)
@@ -127,8 +134,10 @@ class UserFacingPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
         nameString(tp.cls.name)
       else {
         def printPkg(sym: ClassSymbol): Text =
-          if (sym.owner == defn.RootClass) toText(sym)
-          else printPkg(sym.owner.asClass) ~ "." ~ toText(sym)
+          if (sym.owner == defn.RootClass || wrappedName(sym.owner))
+            nameString(sym.name.stripModuleClassSuffix)
+          else
+            printPkg(sym.owner.asClass) ~ "." ~ toText(sym)
 
         printPkg(tp.cls.owner.asClass) ~ "." ~ nameString(tp.cls.name)
       }
diff --git a/repl/test-resources/repl/i2554 b/repl/test-resources/repl/i2554
new file mode 100644
index 000000000000..2830056997be
--- /dev/null
+++ b/repl/test-resources/repl/i2554
@@ -0,0 +1,9 @@
+scala> object foo { trait ShapeLevel; trait FlatShapeLevel extends ShapeLevel; trait ColumnsShapeLevel extends FlatShapeLevel; abstract class Shape[Level <: ShapeLevel, -Mixed, Unpacked, Packed]; object Shape extends TupleShapeImplicits { }; trait TupleShapeImplicits { implicit final def tuple2Shape[Level <: ShapeLevel, M1,M2, U1,U2, P1,P2](implicit u1: Shape[_ <: Level, M1, U1, P1], u2: Shape[_ <: Level, M2, U2, P2]): Shape[Level, (M1,M2), (U1,U2), (P1,P2)] = ???; }; }
+// defined object foo
+scala> import foo._
+scala> implicit val shape: Shape[_ <: FlatShapeLevel, Int, Int, _] = null
+implicit val shape: foo.Shape[_ <: foo.FlatShapeLevel, Int, Int, _] = null
+scala> def hint = Shape.tuple2Shape(shape, shape)
+def hint: foo.Shape[foo.FlatShapeLevel, Tuple2[Int, Int], Tuple2[Int, Int],
+  Tuple2
+[_, _]]