pkg/matcher: refactor with unittest v0.12 work

test/pretty_print_unminified_test.dart

 // 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.
 
 // This file is for pretty-print tests that rely on the names of various Dart
 // types. These tests will fail when run in minified dart2js, since the names
 // will be mangled. A version of this file that works in minified dart2js is in
 // pretty_print_minified_test.dart.
 
 library matcher.print_unminified_test;
 
 import 'dart:collection';
 
 import 'package:matcher/matcher.dart';
 import 'package:matcher/src/pretty_print.dart';
-import 'package:unittest/unittest.dart' show test, group;
+import 'package:unittest/unittest.dart' show test, group, expect;
 
 class DefaultToString {}
 
 class CustomToString {
   String toString() => "string representation";
 }
 
 class _PrivateName {
   String toString() => "string representation";
 }
@@ skipping 24 matching lines @@
     test("that's not a list", () {
       expect(prettyPrint([1, 2, 3, 4].map((n) => n * 2)),
           equals("MappedListIterable:[2, 4, 6, 8]"));
     });
 
     test("that's not a list and has a private name", () {
       expect(prettyPrint(new _PrivateNameIterable()), equals("?:[1, 2, 3]"));
     });
   });
 }