pkg/front_end/testcases/regress/issue_31171.dart

// 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
main() {}

typedef T = 
typedef F = Map<String, dynamic> Function();