Our nice new mismatched type error messages are garbled by minification.

pkg/unittest/test/matchers_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.
 
 library unittestTests;
 import 'package:unittest/unittest.dart';
 import 'dart:async';
 part 'test_utils.dart';
 
 doesNotThrow() {}
@@ skipping 231 matching lines @@
       b.add(0);
       shouldFail(b, hasLength(1),
         "Expected: an object with length of <1> "
         "but: was <[0, 0]> with length of <2>.");
       shouldPass(b, hasLength(2));
     });
 
     test('type mismatch', () {
       var a = new DateTime.utc(2000);
       var b = a.toString();
+      // We should get something like:
+      //    Expected: '2000-01-01 00:00:00.000Z'
+      //    but: expected String:'2000-01-01 00:00:00.000Z'
+      //    but was DateTime:<2000-01-01 00:00:00.000Z>.
+      // However, if minification is applied, then the type names
+      // will be shortened to two letters. The key thing is that
+      // there will be a "but: expected" part in the middle;
+      // this only happens with type mismatches or mismatches
+      // inside container types.
       shouldFail(a, equals(b),
-          "Expected: '2000-01-01 00:00:00.000Z' "
-          "but: expected String:'2000-01-01 00:00:00.000Z' "
-          "but was DateTime:<2000-01-01 00:00:00.000Z>.");
+          matches(new RegExp("^Expected.*but: expected .*but was.*\$")));
     });
   });
 
   group('Numeric Matchers', () {
 
     test('greaterThan', () {
       shouldPass(10, greaterThan(9));
       shouldFail(9, greaterThan(10),
         "Expected: a value greater than <10> but: was <9>.");
     });
@@ skipping 439 matching lines @@
       var w = new Widget();
       w.price = 10;
       shouldPass(w, new HasPrice(greaterThan(0)));
       shouldFail(w, new HasPrice(greaterThan(10)),
           'Expected: Widget with a price that is a value greater than <10> '
           'but: price was <10>.');
     });
   });
 }