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packages/unittest/lib/unittest.dart

 // 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.
 
 library unittest;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'src/configuration.dart';
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 /// Creates a test environment running in its own zone scope.
 ///
 /// This allows for multiple invocations of the unittest library in the same
 /// application instance. This is useful when, for example, creating a test
 /// runner application which needs to create a new pristine test environment on
 /// each invocation to run a given set of tests.
 withTestEnvironment(callback()) {
   return runZoned(callback,
       zoneValues: {#unittest.environment: new TestEnvironment()});
 }