Work around dart2js' broken implementation of runtimeType.

pkg/unittest/lib/src/core_matchers.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.
 
 part of matcher;
 
 /**
  * Returns a matcher that matches empty strings, maps or iterables
  * (including collections).
  */
@@ skipping 155 matching lines @@
                     'with key <${key}> ${location}', depth+1);
                 if (reason != null) {
                   break;
                 }
               }
             }
           }
         }
       } else {
         reason = new StringDescription();
-        var includeTypes = expected.runtimeType != actual.runtimeType;
+        var eType = typeName(expected);
+        var aType = typeName(actual);
+        var includeTypes = eType != aType;
         // If we have recursed, show the expected value too; if not,
         // expect() will show it for us. As expect will not show type
         // mismatches at the top level we handle those here too.
         if (includeTypes || depth > 1) {
           reason.add('expected ');
           if (includeTypes) {
-            reason.add(expected.runtimeType.toString()).add(':');
+            reason.add(eType).add(':');
           }
           reason.addDescriptionOf(expected).add(' but ');
         }
         reason.add('was ');
         if (includeTypes) {
-          reason.add(actual.runtimeType.toString()).add(':');
+          reason.add(aType).add(':');
         }
         reason.addDescriptionOf(actual);
       }
     }
     if (reason != null && location.length > 0) {
       reason.add(' ').add(location);
     }
     return reason;
   }
 
+  String typeName(x) {
+    // dart2js blows up on some objects (e.g. window.navigator).
+    // So we play safe here.

[Siggi Cherem (dart-lang), 2013/02/12 23:09:17]

please file a bug and add a reference here, I'm pretty sure kasper and stephen
would be interested in this issue.

+    try {
+      if (x == null) return "null";
+      return x.runtimeType.toString();
+    } catch (e) {
+      return "Unknown";
+    }
+  }
+
   String _match(expected, actual) {
     Description reason = _recursiveMatch(expected, actual, '', 0);
     return reason == null ? null : reason.toString();
   }
 
   // TODO(gram) - see if we can make use of matchState here to avoid
   // recursing again in describeMismatch.
   bool matches(item, MatchState matchState) => _match(_expected, item) == null;
 
   Description describe(Description description) =>
@@ skipping 512 matching lines @@
       description.add(_featureDescription).add(' ').addDescriptionOf(_matcher);
 
   Description describeMismatch(item, Description mismatchDescription,
                                MatchState matchState, bool verbose) {
     mismatchDescription.add(_featureName).add(' ');
     _matcher.describeMismatch(matchState.state['feature'], mismatchDescription,
         matchState.state['innerState'], verbose);
     return mismatchDescription;
   }
 }