blob: 4820de21b7a4d17b63fbbf9bda83636790305c1a [file] [log] [blame]
// Copyright (c) 2016, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
import "package:expect/expect.dart";
class B {}
class A {
B? x, y;
// Promotion occurs for the initializing formal because C <: B.
A(this.x) : y = (x is C) ? x.x : x;
class C extends A implements B {
C(B? x) : super(x);
main() {
C c = new C(null);
C cc = new C(c);
Expect.equals(c.y, null);
Expect.equals(cc.y, null);