pkg/front_end/testcases/patterns/issue51739.dart

// Copyright (c) 2023, 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.

method() {
  int? q = 2 as dynamic;
  if (q case (var x! || String x)) {
    print(x); // "2"
    print([x].runtimeType); // List<dynamic> / JSArray<dynamic>
  }
}