Language/Expressions/Equality/evaluation_super_t02.dart

// Copyright (c) 2011, 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 Evaluation of an equality expression ee of the form super == e
 * proceeds as follows:
 * • The expression e is evaluated to an object o.
 * • If either this or o is null, then ee evaluates to evaluates to true if both
 *   this and o are null and to false otherwise. Otherwise ee is equivalent to
 *   the method invocation super.==(o).
 * @description Checks that if nnbd is turned on and [o] is [null], the operator
 * super [==(o)] is called and no exception is thrown.
 * @author msyabro
 * @issue https://github.com/dart-lang/co19/issues/871
 */
// Requirements=nnbd-strong
import '../../../Utils/expect.dart';

class S {
  operator ==(other) {
    return false;
  }
}

class C extends S {
  test() {
    dynamic n = null;
    Expect.isFalse(super == n);
  }
}

main() {
  new C().test();
}