LanguageFeatures/nnbd/weak/overriding/override_checking_A05_t07.dart

// 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 If a class [C] in a legacy library implements the same generic
/// class [I] more than once, it is an error if the [LEGACY_ERASURE] of all such
/// super-interfaces are not all syntactically equal. For the purposes of runtime
/// subtyping checks, [C] is considered to implement the canonical
/// [LEGACY_ERASURE] of the super-interfaces in question.
///
/// Using the legacy erasure for checking super-interfaces accounts for opted-out
/// classes which depend on both opted-in and opted-out versions of the same
/// generic interface.
///
///  //opted in
///  class I<T> {}
///
///  // opted in
///  class A implements I<int?> {}
///
///  // opted out
///  class B implements I<int> {}
///
///  // opted out
///  class C extends A implements B {}
///
///  The class [C] is not considered erroneous, despite implementing both
///  [I<int?>] and [I<int*>], since legacy erasure makes both of those interfaces
///  equal. The canonical interface which [C] is chosen to implement for the
///  purposes of runtime type checks is [I<int*>].
///
/// @description Check that error occurs if a class implements the same generic
/// class more than once the [LEGACY_ERASURE] of all such super-interfaces are
/// not all syntactically equal and all passes otherwise. Test [FutureOr] legacy
/// type parameter.
///
/// @author iarkh@unipro.ru

// Requirements=nnbd-weak
// @dart=2.6

import "dart:async";
import "override_checking_A05_opted_in_lib.dart";

class B implements A<FutureOr> {}

class B_FutureOr extends in_FutureOr implements B {}

class B_nullable_int extends in_nullable_int implements B {}
//    ^^^^^^^^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_nullable_Function extends in_nullable_Function implements B {}
//    ^^^^^^^^^^^^^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_nullable_Object extends in_Nullable_Object implements B {}
//    ^^^^^^^^^^^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_int extends in_int implements B {}
//    ^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_Function extends in_Function implements B {}
//    ^^^^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_Object extends in_Object implements B {}
//    ^^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_dynamic extends in_dynamic implements B {}
//    ^^^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_void extends in_void implements B {}
//    ^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_Null extends in_Null implements B {}
//    ^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_Never extends in_Never implements B {}
//    ^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_FutureOr_int extends in_FutureOr_int implements B {}
//    ^^^^^^^^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

class B_FutureOr_FutureOr extends in_FutureOr_FutureOr implements B {}
//    ^^^^^^^^^^^^^^^^^^^
// [analyzer] unspecified
// [cfe] unspecified

main() {}