|  | // Copyright (c) 2017, 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'; | 
|  |  | 
|  | /// Dart2js only supports the const constructor for `?.fromEnvironment`. The | 
|  | /// current behavior is to throw at runtime if they call this constructor with | 
|  | /// `new` instead of `const`. | 
|  | main() { | 
|  | Expect.isFalse(const bool.fromEnvironment('X')); | 
|  | Expect.equals('', const String.fromEnvironment('X', defaultValue: '')); | 
|  | Expect.equals(const int.fromEnvironment('X', defaultValue: 0), 0); | 
|  |  | 
|  | Expect.throws(() => new bool.fromEnvironment('X')); | 
|  | Expect.throws(() => new String.fromEnvironment('X')); | 
|  | Expect.throws(() => new int.fromEnvironment('X', defaultValue: 0)); | 
|  | } |