SI-7853 A less ad-hoc place to call memberType

Rather than localizing the fix to the outerAccessor, this
commit pushed the call to `memberType` into *all* usages of
`newValDef` and `newDefDef`.

The TPT of `applyOrElse` in synthetized partial functions must
be set explicitly to pass the pos/t7853-partial-function.scala.
Otherwise, the as-seen-from ends up cloning the type parameter
`B1` of `applyOrElse` as it transforms (questionably)
its bound from `List[Int @unchecked]` to `List[Int]`.

Partial Function synthesis was already a delicate area, and this
makes things more explicit which could be counted as an improvement.

3 files changed, 9 insertions, 6 deletions

diff --git a/src/compiler/scala/tools/nsc/transform/ExplicitOuter.scala b/src/compiler/scala/tools/nsc/transform/ExplicitOuter.scala
index ff750face5..540b8f6c6c 100644
--- a/src/compiler/scala/tools/nsc/transform/ExplicitOuter.scala
+++ b/src/compiler/scala/tools/nsc/transform/ExplicitOuter.scala
@@ -363,8 +363,7 @@ abstract class ExplicitOuter extends InfoTransform
     def outerAccessorDef: Tree = localTyper typed {
       val acc = outerAccessor(currentClass)
       val rhs = if (acc.isDeferred) EmptyTree else Select(This(currentClass), outerField(currentClass))
-      val tp = (currentClass.thisType memberType acc).finalResultType
-      newDefDef(acc, rhs)(tpt = TypeTree(tp))
+      DefDef(acc, rhs)
     }
 
     /** The definition tree of the outer accessor for class mixinClass.
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index 3ac0b398ee..55268b1e1a 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -2606,7 +2606,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper
         }
 
         val rhs    = methodBodyTyper.virtualizedMatch(match_, mode, B1.tpe)
-        val defdef = newDefDef(methodSym, rhs)(vparamss = mapParamss(methodSym)(newParam))
+        val defdef = newDefDef(methodSym, rhs)(vparamss = mapParamss(methodSym)(newParam), tpt = TypeTree(B1.tpe))
 
         (defdef, matchResTp)
       }
diff --git a/src/reflect/scala/reflect/internal/Trees.scala b/src/reflect/scala/reflect/internal/Trees.scala
index 38f1f0f725..2163a26b84 100644
--- a/src/reflect/scala/reflect/internal/Trees.scala
+++ b/src/reflect/scala/reflect/internal/Trees.scala
@@ -589,7 +589,11 @@ trait Trees extends api.Trees { self: SymbolTable =>
   object TypeTree extends TypeTreeExtractor
 
   def TypeTree(tp: Type): TypeTree = TypeTree() setType tp
-  def TypeTree(sym: Symbol): TypeTree = atPos(sym.pos.focus)(TypeTree(sym.tpe_*.finalResultType))
+  private def TypeTreeMemberType(sym: Symbol): TypeTree = {
+    // Needed for pos/t4970*.scala. See SI-7853
+    val resType = (sym.owner.thisType memberType sym).finalResultType
+    atPos(sym.pos.focus)(TypeTree(resType))
+  }
 
   def TypeBoundsTree(bounds: TypeBounds): TypeBoundsTree = TypeBoundsTree(TypeTree(bounds.lo), TypeTree(bounds.hi))
   def TypeBoundsTree(sym: Symbol): TypeBoundsTree        = atPos(sym.pos)(TypeBoundsTree(sym.info.bounds))
@@ -1039,7 +1043,7 @@ trait Trees extends api.Trees { self: SymbolTable =>
   def newValDef(sym: Symbol, rhs: Tree)(
     mods: Modifiers = Modifiers(sym.flags),
     name: TermName  = sym.name.toTermName,
-    tpt: Tree       = TypeTree(sym)
+    tpt: Tree       = TypeTreeMemberType(sym)
   ): ValDef = (
     atPos(sym.pos)(ValDef(mods, name, tpt, rhs)) setSymbol sym
   )
@@ -1049,7 +1053,7 @@ trait Trees extends api.Trees { self: SymbolTable =>
     name: TermName               = sym.name.toTermName,
     tparams: List[TypeDef]       = sym.typeParams map TypeDef,
     vparamss: List[List[ValDef]] = mapParamss(sym)(ValDef),
-    tpt: Tree                    = TypeTree(sym)
+    tpt: Tree                    = TypeTreeMemberType(sym)
   ): DefDef = (
     atPos(sym.pos)(DefDef(mods, name, tparams, vparamss, tpt, rhs)) setSymbol sym
   )