|  | // Copyright (c) 2015, 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 { | 
|  | } | 
|  |  | 
|  | class $B extends A { | 
|  | } | 
|  |  | 
|  | class C implements $B { | 
|  | // Try to clash with dart2js's isCLASS field. | 
|  | var isB = false; | 
|  | var $isB = false; | 
|  | var is$B = false; | 
|  | var is$$B = false; | 
|  | var $is$B = false; | 
|  |  | 
|  | var isA = false; | 
|  | var $isA = false; | 
|  | var is$A = false; | 
|  | var is$$A = false; | 
|  | var $is$A = false; | 
|  | } | 
|  |  | 
|  | int inscrutable(int x) => x == 0 ? 0 : x | inscrutable(x & (x - 1)); | 
|  |  | 
|  | main() { | 
|  | var things = [new A(), new $B(), new C()]; | 
|  |  | 
|  | var a = things[inscrutable(0)]; | 
|  | Expect.isTrue(a is A); | 
|  | Expect.isFalse(a is $B); | 
|  | Expect.isFalse(a is C); | 
|  |  | 
|  | var b = things[inscrutable(1)]; | 
|  | Expect.isTrue(b is A); | 
|  | Expect.isTrue(b is $B); | 
|  | Expect.isFalse(b is C); | 
|  |  | 
|  | var c = things[inscrutable(2)]; | 
|  | Expect.isTrue(c is A); | 
|  | Expect.isTrue(c is $B); | 
|  | Expect.isTrue(c is C); | 
|  | } |