| // Copyright (c) 2018, 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. |
| |
| // @dart = 2.9 |
| |
| import 'dart:async'; |
| |
| /* |
| * `return exp;` where `exp` has static type `S` is an error if |
| `Future<flatten(S)>` is not assignable to `T`. |
| */ |
| Future<Future<String>> v = null; |
| Future<String> test() async { |
| return v; |
| // ^ |
| // [analyzer] COMPILE_TIME_ERROR.RETURN_OF_INVALID_TYPE |
| // [cfe] A value of type 'Future<Future<String>>' can't be assigned to a variable of type 'FutureOr<String>'. |
| } |
| |
| void main() { |
| test(); |
| } |