From 02967c9a8615fcc9bc6192cc7df7881fe8a9e99f Mon Sep 17 00:00:00 2001
From: Tobias Bordenca <tobias.bordenca@epfl.ch>
Date: Wed, 26 Sep 2018 17:18:45 +0200
Subject: [PATCH 1/2] Resugar varargs #4526

Remove annotation from function declaration

Explicitly type non sequence literal arguments as varargs in function call (_*)
---
 .../src/scala/tasty/util/ShowSourceCode.scala | 35 ++++++++++++++++---
 1 file changed, 31 insertions(+), 4 deletions(-)

diff --git a/library/src/scala/tasty/util/ShowSourceCode.scala b/library/src/scala/tasty/util/ShowSourceCode.scala
index 764b0be442bf..98b02d1352c6 100644
--- a/library/src/scala/tasty/util/ShowSourceCode.scala
+++ b/library/src/scala/tasty/util/ShowSourceCode.scala
@@ -344,7 +344,13 @@ class ShowSourceCode[T <: Tasty with Singleton](tasty0: T) extends Show[T](tasty
       case Term.Typed(term, tpt) =>
         tpt.tpe match {
           case Types.Repeated(_) =>
-            printTree(term)
+            term match {
+              case Term.Repeated(_) =>
+                printTree(term)
+              case _ =>
+                printTree(term)
+                this += ": " += highlightTypeDef("_*", color)
+            }
           case _ =>
             inParens {
               printTree(term)
@@ -790,9 +796,16 @@ class ShowSourceCode[T <: Tasty with Singleton](tasty0: T) extends Show[T](tasty
 
       case TypeTree.Annotated(tpt, annot) =>
         val Annotation(ref, args) = annot
-        printTypeTree(tpt)
-        this += " "
-        printAnnotation(annot)
+        ref.tpe match {
+          case Types.RepeatedAnnotation() =>
+            val Types.Sequence(tp) = tpt.tpe
+            printType(tp)
+            this += highlightTypeDef("*", color)
+          case _ =>
+            printTypeTree(tpt)
+            this += " "
+            printAnnotation(annot)
+        }
 
       case TypeTree.And(left, right) =>
         printTypeTree(left)
@@ -1160,6 +1173,20 @@ class ShowSourceCode[T <: Tasty with Singleton](tasty0: T) extends Show[T](tasty
       }
     }
 
+    object Sequence {
+      def unapply(tpe: Type)(implicit ctx: Context): Option[Type] = tpe match {
+        case Type.AppliedType(Type.TypeRef("Seq", Type.SymRef(sym, _)), IsType(tp) :: Nil) if sym.fullName == "scala.collection" => Some(tp)
+        case _ => None
+      }
+    }
+
+    object RepeatedAnnotation {
+      def unapply(tpe: Type)(implicit ctx: Context): Boolean = tpe match {
+        case Type.TypeRef("Repeated", Type.SymRef(sym, _)) if sym.fullName == "scala.annotation.internal" => true
+        case _ => false
+      }
+    }
+
     object Repeated {
       def unapply(tpe: Type)(implicit ctx: Context): Option[Type] = tpe match {
         case Type.AppliedType(Type.TypeRef("<repeated>", ScalaPackage()), IsType(tp) :: Nil) => Some(tp)

From e94f0ef22e79379f71c64317e6c45351b2f96809 Mon Sep 17 00:00:00 2001
From: Tobias Bordenca <tobias.bordenca@epfl.ch>
Date: Wed, 17 Oct 2018 12:18:40 +0200
Subject: [PATCH 2/2] Add tests for varargs and put in whitelist

---
 compiler/test/dotc/pos-recompilation.whitelist |  2 ++
 tests/pos/varargs-position.decompiled          | 12 ++++++++++++
 tests/pos/varargs-position.scala               | 12 ++++++++++++
 3 files changed, 26 insertions(+)
 create mode 100644 tests/pos/varargs-position.decompiled
 create mode 100644 tests/pos/varargs-position.scala

diff --git a/compiler/test/dotc/pos-recompilation.whitelist b/compiler/test/dotc/pos-recompilation.whitelist
index 493e103a524c..7100e52e5a05 100644
--- a/compiler/test/dotc/pos-recompilation.whitelist
+++ b/compiler/test/dotc/pos-recompilation.whitelist
@@ -38,3 +38,5 @@ t116
 t3869
 t6225b
 t704
+varargs
+varargs-position
diff --git a/tests/pos/varargs-position.decompiled b/tests/pos/varargs-position.decompiled
new file mode 100644
index 000000000000..d4459aa8d560
--- /dev/null
+++ b/tests/pos/varargs-position.decompiled
@@ -0,0 +1,12 @@
+object varargspos {
+  def g(a: scala.Int, x: scala.Int*): scala.Int = a.+(x.length)
+  varargspos.g(1, 2, 3, 4)
+  val xs: collection.immutable.List[scala.Int] = scala.Nil.::[scala.Int](2).::[scala.Int](1)
+  val a: scala.Int = 8
+  val b: scala.Int = 7
+  varargspos.g(5, varargspos.xs: _*)
+  varargspos.g(3, scala.Nil: _*)
+  varargspos.g(varargspos.a, varargspos.xs: _*)
+  varargspos.g(varargspos.a, varargspos.b, 2, 3)
+  varargspos.g(1)
+}
\ No newline at end of file
diff --git a/tests/pos/varargs-position.scala b/tests/pos/varargs-position.scala
new file mode 100644
index 000000000000..e0b1abc43e55
--- /dev/null
+++ b/tests/pos/varargs-position.scala
@@ -0,0 +1,12 @@
+object varargspos {
+  def g(a: Int, x: Int*) = a + x.length
+  g(1, 2, 3, 4)
+  val xs = 1 :: 2 :: Nil
+  val a = 8
+  val b = 7
+  g(5, xs: _*)
+  g(3, Nil: _*)
+  g(a, xs: _*)
+  g(a, b, 2, 3)
+  g(1)
+}