/*
 * Copyright (c) 2019, 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 It is a warning to use a null aware operator (?., ?.., ??, ??=,
 * or ...?) on an expression of type T if T is strictly non-nullable.
 *
 * @description Check it is a warning to use a null aware operator (?., ?.., ??,
 * ??=, or ...?) on a strictly non-nullable receiver. Test FutureOr<Function>
 * @author sgrekhov@unipro.ru
 * @issue 39598
 * @issue 39714
 */
// SharedOptions=--enable-experiment=non-nullable
// Requirements=nnbd-strong
import "dart:async";

void foo() {}

main() {
  FutureOr<Function> f = foo;
  f?.toString();                                  //# 01: static type warning
  f?..toString();                                 //# 02: static type warning
  f ?? f;                                         //# 03: static type warning
  f ??= f;                                        //# 04: static type warning
  List<FutureOr<Function>> clist = [f, f];
  List<FutureOr<Function>> alist = [f, f, ...? clist]; //# 05: static type warning
}