blob: edf7e934ed3395475ed6761427251440ffb94674 [file] [log] [blame]
// 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<X> {
void f(X x);
}
// This class contains a forwarding stub for f to allow it to satisfy the
// interface I<B>, 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<B> {}
class E extends D {
void test() {
I0 i0 = null;
B2 b2 = null;
// ok since I0 is assignable to B
// TODO: Downcast from I0 to B will be a compile-time error with NNBD.
super.f(i0);
// not ok since B2 is not assignable to B
super.f(b2);
// ^^
// [analyzer] COMPILE_TIME_ERROR.ARGUMENT_TYPE_NOT_ASSIGNABLE
// [cfe] The argument type 'B2' can't be assigned to the parameter type 'B'.
var superF = super.f; // Inferred static type: void Function(B)
// ok since I0 is assignable to B
// TODO: Downcast from I0 to B will be a compile-time error with NNBD.
superF(i0);
// not ok since B2 is not assignable to B
superF(b2);
// ^^
// [analyzer] COMPILE_TIME_ERROR.ARGUMENT_TYPE_NOT_ASSIGNABLE
// [cfe] The argument type 'B2' can't be assigned to the parameter type 'B'.
// Should pass since superF's runtime type is void Function(Object)
Expect.isTrue(superF is void Function(B));
Expect.isTrue(superF is void Function(I0));
Expect.isTrue(superF is void Function(A));
Expect.isTrue(superF is void Function(Object));
}
}
main() {
new E().test();
}