| // Copyright (c) 2019, 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 |
| |
| /// @assertion Since the spread is unpacked and its individual elements added to |
| /// the containing collection, we don't require the spread expression itself to |
| /// be assignable to the collection's type. For example, this is allowed: |
| /// |
| /// var numbers = <num>[1, 2, 3]; |
| /// var ints = <int>[...numbers]; |
| /// |
| /// This works because the individual elements in numbers do happen to have the |
| /// right type even though the list that contains them does not. As long as the |
| /// spread object is "spreadable" — it implements [Iterable] — there is no |
| /// static error. |
| /// @description Checks that for sets it's possible to have the spread |
| /// expression which is not assignable to the result collection type, no static |
| /// error in this case. |
| /// @author iarkh@unipro.ru |
| |
| |
| import "../../Utils/expect.dart"; |
| |
| main() { |
| var numbers = <num>[1, 2, 3]; |
| Expect.setEquals(<int>{1, 2, 3}, <int>{...numbers}); |
| |
| var objects = <Object>[2, 7, 9]; |
| Expect.setEquals(<int>{2, 7, 9}, <int>{...objects}); |
| |
| var a; |
| Expect.throws(() => a = <String>{...objects}); |
| |
| var numbers1 = <num>[1.1, 2, 3]; |
| Expect.throws(() => a = <int>{...numbers1}); |
| |
| |
| numbers = <num>[1, 2, 3]; |
| Expect.setEquals(<int>{1, 2, 3}, <int>{...?numbers}); |
| |
| objects = <Object>[2, 7, 9]; |
| Expect.setEquals(<int>{2, 7, 9}, <int>{...?objects}); |
| |
| Expect.throws(() => a = <String>{...?objects}); |
| |
| numbers1 = <num>[1.1, 2, 3]; |
| Expect.throws(() => a = <int>{...?numbers1}); |
| } |