dart-sdk/tests/language_2/issue31596_super_test.dart
Paul Berry 236ea5bb44 Add further test cases reflecting the consensus on #31596.
Change-Id: Ib67f8ae239b89bf56efc059054b6430e27a0e66f
Reviewed-on: https://dart-review.googlesource.com/34922
Commit-Queue: Paul Berry <paulberry@google.com>
Reviewed-by: Erik Ernst <eernst@google.com>
2018-01-20 17:10:57 +00:00

60 lines
1.5 KiB
Dart

// Copyright (c) 2018, 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 I0 {}
class A {}
class B extends A implements I0 {}
class B2 extends A {}
class C {
void f(B x) {}
}
abstract class I {
void f(covariant A x);
}
// This class contains a forwarding stub for f to allow it to satisfy the
// interface I, while still ensuring that the x argument is type checked before
// C.f is executed.
//
// Super calls in a derived class resolve directly to C.f, and are type checked
// accordingly at compile time.
class D extends C implements I {}
class E extends D {
void test() {
I0 i0 = null;
B2 b2 = null;
// ok since I0 is assignable to B
super.f(i0); //# 01: ok
// not ok since B2 is not assignable to B
super.f(b2); //# 02: compile-time error
var superF = super.f; // Inferred type: (B) -> void
// ok since I0 is assignable to B
superF(i0); //# 03: ok
// not ok since B2 is not assignable to B
superF(b2); //# 04: compile-time error
// Should pass since superF's runtime type is (B) -> void
Expect.isTrue(superF is void Function(B)); //# 05: ok
Expect.isTrue(superF is! void Function(I0)); //# 05: continued
Expect.isTrue(superF is! void Function(A)); //# 05: continued
Expect.isTrue(superF is! void Function(Object)); //# 05: continued
}
}
main() {
new E().test();
}