LanguageFeatures/Simple-bounds/static/typedef_FutureOr_l1_t02.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.

/**
 * @assertion Let [G] be a generic class or parameterized type alias with formal
 * type parameter declarations [F1] .. [Fk] containing formal type parameters
 * [X1] .. [Xk] and bounds [B1] .. [Bk]. We say that the formal type parameter
 * [Xj] has a simple bound when one of the following requirements is satisfied:
 * [Bj] is omitted.
 * [Bj] is included, but does not contain any of [X1] .. [Xk]. If [Bj] contains
 * a type [T] on the form qualified (for instance, [C] or [p.D]) which denotes a
 * generic class or parameterized type alias [G1] (that is, [T] is a raw type),
 * every type argument of [G1] has a simple bound.
 * @description Checks that simple bounds are correct for the contravariant
 * FutureOr case: [typedef G<X extends FutureOr> = Function(X)]. This should be
 * [G<FutureOr<dynamic>>]. A raw [G] has a bound, [FutureOr], which means
 * [FutureOr<dynamic>], and that bound is simply the initial and final value of
 * the i2b value of [X]. No cycles, no dependencies between type variables,
 * we're just done immediately.
 * @author iarkh@unipro.ru
 */

import "dart:async";
import "../../../Utils/expect.dart";

typedef G<X extends FutureOr> = Function(X);

test(G source) {
  var fsource = toF(source);

  F<G<FutureOr<dynamic>>> target1 = fsource;

  F<G<FutureOr<Never>>> target = fsource;
//                               ^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

  F<G<FutureOr<Null>>> target0 = fsource;
//                               ^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified
}

main() {}