blob: 3a3e7bf8cc7dc0a8fa72d4e79be5e3c638ebcaf9 [file] [log] [blame]
// TODO(multitest): This was automatically migrated from a multitest and may
// contain strange or dead code.
// Copyright (c) 2013, 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.
// Test use of more specific in type promotion of interface types.
class A {
var a;
}
class B extends A {
var b;
}
class C {
var c;
}
class D<T> {
T? d;
D(this.d);
}
class E<T> extends D<T> {
T? e;
E(e)
: this.e = e,
super(e);
}
void main() {
testInterface();
testGeneric();
}
void testInterface() {
var x;
var y;
A a = new B();
if (a is B) {
// Promotion B << A.
}
if (a is C) {
// No promotion C !<< A.
}
B b = new B();
if (b is A) {
// No promotion B !<< A.
}
if (x is A) {
// Promotion A << dynamic.
}
}
testGeneric() {
var x;
var y;
D d1 = new E<B>(null);
if (d1 is E) {
// Promotion: E << D.
}
if (d1 is E<A>) {
// Promotion: E<A> << D.
}
D<A> d2 = new E<B>(null);
if (d2 is E) {
// No promotion: E !<< D<A>
}
D<A> d3 = new E<B>(new B());
if (d3 is E<B>) {
// Promotion: E<B> << D<A>
}
}