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test/file_test.dart

 // Copyright (c) 2014, 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:unittest/unittest.dart';
+import 'package:test/test.dart';
 import 'package:source_span/source_span.dart';
 
 main() {
   var file;
   setUp(() {
     file = new SourceFile("""
 foo bar baz
 whiz bang boom
 zip zap zop""", url: "foo.dart");
   });
@@ skipping 351 matching lines @@
         expect(span.expand(other), equals(span));
       });
 
       test("works with an external overlapping span", () {
         var other = file.span(0, 16);
         expect(span.expand(other), equals(other));
       });
     });
   });
 }