LanguageFeatures/nnbd/weak/overriding/override_checking_A01_REQ_ARGS_t25.dart

// Copyright (c) 2020, 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.

/**
 * @assertion In an unmigrated library, override checking is done using legacy
 * types. This means that an unmigrated library can bring together otherwise
 * incompatible methods. When choosing the most specific signature during
 * interface computation, all nullability and requiredness annotations are
 * ignored, and the [Never] type is treated as [Null].
 *
 * @description Check that if legacy class extends legacy class and implements
 * opted-in class, legacy method with optional named argument with default
 * [null] value can override method with [required] argument.
 *
 * @author iarkh@unipro.ru
 */
// Requirements=nnbd-weak
// @dart=2.6

import "../../../../Utils/expect.dart";
import "override_checking_A01_opted_in_lib.dart";

class A extends B implements OPTED_REQUIRED_ARGS {}

class B {
  void test_required_nonnullable({int i = null}) { Expect.isNull(i); }
  void test_required_nullable   ({int i = null}) { Expect.isNull(i); }
}

main() {
  A a = A();
  a.test_required_nonnullable();
  a.test_required_nullable();
}