fix long stable path

Author: noti0na1

compiler/src/dotty/tools/dotc/core/Types.scala

@@ -163,6 +163,7 @@ object Types {
       case tp: RefinedOrRecType => tp.parent.isStable
       case tp: ExprType => tp.resultType.isStable
       case tp: AnnotatedType => tp.parent.isStable
+      case tp: AndType => tp.tp1.isStable || tp.tp2.isStable
       case _ => false
     }
 

compiler/src/dotty/tools/dotc/typer/Nullables.scala

@@ -95,36 +95,26 @@ object Nullables with
 
   /** An extractor for null-trackable references */
   object TrackedRef
-    def unapply(tree: Tree)(given Context): Option[TermRef] = isTracked(tree)
+    def unapply(tree: Tree)(given Context): Option[TermRef] = tree.typeOpt match
+      case ref: TermRef if isTracked(ref) => println("tr: " + ref); Some(ref)
+      case _ => None
   end TrackedRef
 
   /** Is given reference tracked for nullability?
    *  This is the case if the reference is a path to an immutable val, or if it refers
    *  to a local mutable variable where all assignments to the variable are _reachable_
    *  (in the sense of how it is defined in assignmentSpans).
    */
-  def isTracked(tree: Tree)(given Context): Option[TermRef] = tree.typeOpt match
-    case ref: TermRef
-    if ref.isStable
-    || isTrackedNotNull(tree)
+  def isTracked(ref: TermRef)(given Context) =
+    ref.isStable
     || { val sym = ref.symbol
-        sym.is(Mutable)
-        && sym.owner.isTerm
-        && sym.owner.enclosingMethod == curCtx.owner.enclosingMethod
-        && sym.span.exists
-        && curCtx.compilationUnit != null // could be null under -Ytest-pickler
-        && curCtx.compilationUnit.assignmentSpans.contains(sym.span.start)
-      } =>
-      Some(ref)
-    case _ => None
-
-  def isTrackedNotNull(tree: Tree)(given Context) = tree match
-    case Select(Apply(TypeApply(f: Ident, _), x :: Nil), _) =>
-      f.symbol == defn.Compiletime_notNull
-      && tree.symbol.isStableMember
-      && isTracked(x).isDefined
-    case _ =>
-      false
+         sym.is(Mutable)
+         && sym.owner.isTerm
+         && sym.owner.enclosingMethod == curCtx.owner.enclosingMethod
+         && sym.span.exists
+         && curCtx.compilationUnit != null // could be null under -Ytest-pickler
+         && curCtx.compilationUnit.assignmentSpans.contains(sym.span.start)
+      }
 
   /** The nullability context to be used after a case that matches pattern `pat`.
    *  If `pat` is `null`, this will assert that the selector `sel` is not null afterwards.