dart-sdk/tests/language/covariant/field_test.dart
Robert Nystrom 5f655a8c27 Migrate language_2/covariant to NNBD.
Change-Id: Icb4eae77fab5257ea00ff948d3f775725398e6ab
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/142067
Commit-Queue: Bob Nystrom <rnystrom@google.com>
Auto-Submit: Bob Nystrom <rnystrom@google.com>
Reviewed-by: Erik Ernst <eernst@google.com>
2020-04-07 01:05:28 +00:00

59 lines
1.8 KiB
Dart

// Copyright (c) 2017, 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.
import "package:expect/expect.dart";
class A {}
abstract class B<T> {
// x will be marked genericCovariantInterface, since x's type is covariant in
// the type parameter T.
void set s2(T x);
// x will be marked genericCovariantInterface, since x's type is covariant in
// the type parameter T.
void set s3(T x);
void set s4(Object? x);
void set s5(Object? x) {
s4 = x;
}
}
class C extends B<A> {
A? s1;
// s2 will be marked genericCovariantImpl, since it might be called via
// e.g. B<Object>.
A? s2;
// s3 will be marked genericCovariantImpl, since it might be called via
// e.g. B<Object>.
covariant A? s3;
covariant A? s4;
}
main() {
// Dynamic method calls should always have their arguments type checked.
dynamic d = new C();
Expect.throwsTypeError(() => d.s1 = new Object()); //# 01: ok
// Interface calls should have any arguments marked "genericCovariantImpl"
// type checked provided that the corresponding argument on the interface
// target is marked "genericCovariantInterface".
B<Object> b = new C();
Expect.throwsTypeError(() => b.s2 = new Object()); //# 02: ok
// Interface calls should have any arguments marked "covariant" type checked,
// regardless of whether the corresponding argument on the interface target is
// marked "genericCovariantInterface".
Expect.throwsTypeError(() => b.s3 = new Object()); //# 03: ok
Expect.throwsTypeError(() => b.s4 = new Object()); //# 04: ok
// This calls should have any arguments marked "covariant" type checked.
Expect.throwsTypeError(() => b.s5 = new Object()); //# 05: ok
}