tests/language/why_not_promoted/extension_property_error_test.dart

// Copyright (c) 2021, 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.

class C {
  get_property_via_explicit_this() {
    if (this.i == null) return;
    this.i.isEven;
//  ^^^^^^
// [analyzer] COMPILE_TIME_ERROR.UNCHECKED_USE_OF_NULLABLE_VALUE
//         ^
// [cfe 1] Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
  }

  get_property_via_explicit_this_parenthesized() {
    if ((this).i == null) return;
    (this).i.isEven;
//  ^^^^^^^^
// [analyzer] COMPILE_TIME_ERROR.UNCHECKED_USE_OF_NULLABLE_VALUE
//           ^
// [cfe 2] Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
  }

  get_property_by_implicit_this() {
    if (i == null) return;
    i.isEven;
//  ^
// [analyzer] COMPILE_TIME_ERROR.UNCHECKED_USE_OF_NULLABLE_VALUE
//    ^
// [cfe 3] Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
  }
}

extension E on C {
  int? get i => null;
  //       ^
  // [context 1] 'i' refers to a property so it couldn't be promoted.
  // [context 2] 'i' refers to a property so it couldn't be promoted.
  // [context 3] 'i' refers to a property so it couldn't be promoted.
  // [context 4] 'i' refers to a property so it couldn't be promoted.
  // [context 5] 'i' refers to a property so it couldn't be promoted.
  int? get j => null;
}

class D extends C {
  get_property_by_implicit_super() {
    if (i == null) return;
    i.isEven;
//  ^
// [analyzer] COMPILE_TIME_ERROR.UNCHECKED_USE_OF_NULLABLE_VALUE
//    ^
// [cfe 4] Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
  }
}

get_property_via_prefixed_identifier(C c) {
  if (c.i == null) return;
  c.i.isEven;
//^^^
// [analyzer] COMPILE_TIME_ERROR.UNCHECKED_USE_OF_NULLABLE_VALUE
//    ^
// [cfe 5] Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
}

get_property_via_prefixed_identifier_mismatched_target(C c1, C c2) {
  // Note: no context on this error because the property the user is attempting
  // to promote is on c1, but the property the user is accessing is on c2.
  if (c1.i == null) return;
  c2.i.isEven;
//^^^^
// [analyzer] COMPILE_TIME_ERROR.UNCHECKED_USE_OF_NULLABLE_VALUE
//     ^
// [cfe] Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
}

get_property_via_prefixed_identifier_mismatched_property(C c) {
  // Note: no context on this error because the property the user is attempting
  // to promote is C.i, but the property the user is accessing is C.j.
  if (c.i == null) return;
  c.j.isEven;
//^^^
// [analyzer] COMPILE_TIME_ERROR.UNCHECKED_USE_OF_NULLABLE_VALUE
//    ^
// [cfe] Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
}