mirror of
https://github.com/dart-lang/sdk
synced 2024-09-05 16:41:07 +00:00
b101a7d002
Change-Id: Ib33169c3e0ffc870915c189404074a1dea472546 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/196548 Reviewed-by: Bob Nystrom <rnystrom@google.com> Commit-Queue: Leaf Petersen <leafp@google.com>
49 lines
1.2 KiB
Dart
49 lines
1.2 KiB
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.
|
|
|
|
// @dart = 2.9
|
|
|
|
import "dart:collection";
|
|
import "package:expect/expect.dart";
|
|
import 'cast_helper.dart';
|
|
|
|
void main() {
|
|
testDowncast();
|
|
testUpcast();
|
|
testRegression();
|
|
}
|
|
|
|
void testDowncast() {
|
|
var list = new List<C>.from(elements);
|
|
var dList = List.castFrom<C, D>(list);
|
|
|
|
Expect.throws(() => dList.first); // C is not D.
|
|
Expect.equals(d, dList[1]);
|
|
Expect.throws(() => dList[2]); // E is not D.
|
|
Expect.equals(f, dList[3]);
|
|
Expect.equals(null, dList.last);
|
|
|
|
Expect.throws(() => dList.toList());
|
|
|
|
// Setting works.
|
|
dList[2] = d;
|
|
Expect.equals(d, dList[2]);
|
|
}
|
|
|
|
void testUpcast() {
|
|
var list2 = new List<C>.from(elements);
|
|
var dList2 = List.castFrom<C, Object>(list2);
|
|
Expect.listEquals(elements, dList2);
|
|
Expect.throws(() => dList2[2] = new Object()); // Cannot set non-C.
|
|
Expect.listEquals(elements, dList2);
|
|
}
|
|
|
|
void testRegression() {
|
|
var numList = <num>[4, 3, 2, 1];
|
|
var intList = numList.cast<int>();
|
|
intList.sort(null);
|
|
Expect.listEquals([1, 2, 3, 4], numList);
|
|
Expect.listEquals([1, 2, 3, 4], intList);
|
|
}
|