blob: 400261be969fa8b6a2008ac4b6fed63d97f149fb [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 Checks the type of [await] expression: neither compile nor
/// runtime errors is not thrown in nnbd-weak mode if [A] is a legacy class,
/// synchronous function returns a value of [Future<A>] type which is set to
/// [null].
/// @Issue
/// @Issue
/// @Issue
/// @Issue 41266,41437,42236,42237
/// @author
// Requirements=nnbd-weak
import "dart:async";
import "../../../Utils/expect.dart";
import "future_flattening_legacy_lib.dart";
dynamic getNull() => null;
Future<A> test() async => await getNull();
main() {
test().then((value) => asyncEnd());