| // 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 N is an expression of the form E1.m1(E2), then: |
| /// |
| /// Let before(E1) = before(N) |
| /// Let before(E2) = after(E2) |
| /// Let T be the static return type of the invocation |
| /// If T <: Never then: |
| /// Let null(N) = unreachable(before(N)). |
| /// Let notNull(N) = unreachable(before(N)). |
| /// Otherwise if T <: Null then: |
| /// Let null(N) = before(N). |
| /// Let notNull(N) = unreachable(before(N)). |
| /// Otherwise if T is non-nullable then: |
| /// Let null(N) = before(N). |
| /// Let notNull(N) = unreachable(before(N)). |
| /// Otherwise: |
| /// Let null(N) = promote(x, Null, before(N)) |
| /// Let notNull(N) = promoteToNonNull(x, before(N)) |
| /// |
| /// @description Checks reachability after method call. Test return type T <: Null |
| /// |
| /// @author sgrekhov@unipro.ru |
| /// @issue 41981 |
| |
| |
| class C { |
| Null m1() => null; |
| } |
| |
| main() { |
| C c = new C(); |
| late int i; |
| if (c.m1() != null) { |
| i = 42; // Variable is initialized in a dead code. This leaves it definitely unassigned |
| } |
| i; // It is an error to read a local late variable when it is definitely unassigned. |
| //^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| } |