blob: 84fbfcae91a1313d1d0419154d79e086a2fb1a4a [file] [log] [blame]
// 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 The flatten function is modified as follows:
///
/// [flatten(T)] is defined by cases on [T]:
///
/// if [T] is [S?] then [flatten(T) = flatten(S)?]
/// otherwise if [T] is [S*] then [flatten(T) = flatten(S)*]
/// otherwise if [T] is [FutureOr<S>] then [flatten(T) = S]
/// otherwise [if T <: Future] then let [S] be a type such that [T <:
/// Future<S>] and for all [R], if [T <: Future<R>] then [S <: R]; then
/// [flatten(T) = S]
/// otherwise [flatten(T) = T]
///
/// @description Check that future flattening works correctly for
/// [Future<Object>] type statically and the expression cannot be null.
///
/// @Issue 41339, 41340
/// @author iarkh@unipro.ru
import "dart:async";
main() {
Future<Future<Object?>>(() => Future<Object>(() => null));
// ^^^^
// [analyzer] unspecified
// [cfe] unspecified
}