Merge pull request #2601 from retronym/ticket/7516

SI-7516 Revert "SI-7234 Make named args play nice w. depmet types"

5 files changed, 20 insertions, 5 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/NamesDefaults.scala b/src/compiler/scala/tools/nsc/typechecker/NamesDefaults.scala
index 802df39f01..d54f894c62 100644
--- a/src/compiler/scala/tools/nsc/typechecker/NamesDefaults.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/NamesDefaults.scala
@@ -284,11 +284,13 @@ trait NamesDefaults { self: Analyzer =>
               case Typed(expr, Ident(tpnme.WILDCARD_STAR)) => expr.tpe
               case _                                       => seqType(arg.tpe)
             }
-            else
-              // Note stabilizing can lead to a non-conformant argument when existentials are involved, e.g. neg/t3507-old.scala, hence the filter.
-              // We have to deconst or types inferred from literal arguments will be Constant(_), e.g. pos/z1730.scala.
-              gen.stableTypeFor(arg).filter(_ <:< paramTpe).getOrElse(arg.tpe).deconst
-          )
+            else {
+              // TODO In 83c9c764b, we tried to a stable type here to fix SI-7234. But the resulting TypeTree over a
+              //      singleton type without an original TypeTree fails to retypecheck after a resetLocalAttrs (SI-7516),
+              //      which is important for (at least) macros.
+              arg.tpe
+            }
+          ).widen // have to widen or types inferred from literal defaults will be singletons
           val s = context.owner.newValue(unit.freshTermName("x$"), arg.pos) setInfo (
             if (byName) functionType(Nil, argTpe) else argTpe
           )
diff --git a/test/files/pos/t7516/A_1.scala b/test/files/pos/t7516/A_1.scala
new file mode 100644
index 0000000000..3bba19966d
--- /dev/null
+++ b/test/files/pos/t7516/A_1.scala
@@ -0,0 +1,9 @@
+import scala.reflect._,macros._, scala.language.experimental.macros
+
+object A {
+  def impl[T: c.WeakTypeTag](c: Context)(t: c.Expr[T]): c.Expr[List[T]] = {
+    val r = c.universe.reify { List(t.splice) }
+    c.Expr[List[T]]( c.resetLocalAttrs(r.tree) )
+  }
+  def demo[T](t: T): List[T] = macro impl[T]
+}
diff --git a/test/files/pos/t7516/B_2.scala b/test/files/pos/t7516/B_2.scala
new file mode 100644
index 0000000000..1b8531bc85
--- /dev/null
+++ b/test/files/pos/t7516/B_2.scala
@@ -0,0 +1,4 @@
+object B {
+  final case class CV(p: Int = 3, g: Int = 2)
+  A.demo { val d = 4; CV(g = d); "a" }
+}
diff --git a/test/files/pos/t7234.scala b/test/pending/pos/t7234.scala
index 59a233d835..59a233d835 100644
--- a/test/files/pos/t7234.scala
+++ b/test/pending/pos/t7234.scala
diff --git a/test/files/pos/t7234b.scala b/test/pending/pos/t7234b.scala
index fee98e87a8..fee98e87a8 100644
--- a/test/files/pos/t7234b.scala
+++ b/test/pending/pos/t7234b.scala