Special-case Tuple/NonEmptyTuple because they're so, so special

Author: dwijnand

compiler/src/dotty/tools/dotc/transform/patmat/Space.scala

@@ -631,6 +631,8 @@ class SpaceEngine(using Context) extends SpaceLogic {
         def getChildren(sym: Symbol): List[Symbol] =
           sym.children.flatMap { child =>
             if child eq sym then Nil // i3145: sealed trait Baz, val x = new Baz {}, Baz.children returns Baz...
+            else if tp.classSymbol == defn.TupleClass || tp.classSymbol == defn.NonEmptyTupleClass then
+              List(child) // TupleN and TupleXXL classes are used for Tuple, but they aren't Tuple's children
             else if (child.is(Private) || child.is(Sealed)) && child.isOneOf(AbstractOrTrait) then getChildren(child)
             else List(child)
           }