|  | // Copyright (c) 2012, 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'; | 
|  | import 'package:async_helper/async_helper.dart'; | 
|  | import '../helpers/compiler_helper.dart'; | 
|  |  | 
|  | const String TEST = r""" | 
|  | foo() { | 
|  | String s = Object().toString(); | 
|  | Object o = Object().toString(); | 
|  | return s == 'foo' | 
|  | && s == null | 
|  | && null == s | 
|  | && null == o; | 
|  | } | 
|  | """; | 
|  |  | 
|  | main() { | 
|  | test() async { | 
|  | await compile(TEST, entry: 'foo', enableTypeAssertions: true, | 
|  | check: (String generated) { | 
|  | Expect.isTrue(!generated.contains('eqB')); | 
|  |  | 
|  | RegExp regexp = RegExp('=='); | 
|  | Iterator<Match> matches = regexp.allMatches(generated).iterator; | 
|  | // `s == null` and `null == s` now both encoded as `s == null` allowing | 
|  | // the second to be optimized away. | 
|  | checkNumberOfMatches(matches, 3); | 
|  | }); | 
|  | } | 
|  |  | 
|  | asyncTest(() async { | 
|  | print('--test from kernel------------------------------------------------'); | 
|  | await test(); | 
|  | }); | 
|  | } |