Improved the way we generate mismatch descriptions.

lib/unittest/operator_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.
 
 /**
  * This returns a matcher that inverts [matcher] to its logical negation.
  */
 Matcher isNot(matcher) => new _IsNot(wrapMatcher(matcher));
 
 class _IsNot extends BaseMatcher {
   final Matcher _matcher;
 
   const _IsNot(Matcher this._matcher);
 
-  bool matches(item) => !_matcher.matches(item);
+  bool matches(item, MatchState matchState) =>
+      !_matcher.matches(item, matchState);
 
   Description describe(Description description) =>
     description.add('not ').addDescriptionOf(_matcher);
 }
 
 /**
  * This returns a matcher that matches if all of the matchers passed as
  * arguments (up to 7) match. Instead of passing the matchers separately
  * they can be passed as a single List argument.
  * Any argument that is not a matcher is implicitly wrapped in a
@@ skipping 42 matching lines @@
     }
     return new _AllOf(matchers);
   }
 }
 
 class _AllOf extends BaseMatcher {
   final Iterable<Matcher> _matchers;
 
   const _AllOf(this._matchers);
 
-  bool matches(item) {
+  bool matches(item, MatchState matchState) {
      for (var matcher in _matchers) {
-       if (!matcher.matches(item)) {
+       if (!matcher.matches(item, matchState)) {
+         matchState.state = {
+             'matcher': matcher,
+             'state': matchState.state
+         };
          return false;
        }
      }
      return true;
   }
 
-  Description describeMismatch(item, Description mismatchDescription) {
-    for (var matcher in _matchers) {
-      if (!matcher.matches(item)) {
-        mismatchDescription.addDescriptionOf(matcher).add(' ');
-        matcher.describeMismatch(item, mismatchDescription);
-        break;
-      }
-    }
+  Description describeMismatch(item, Description mismatchDescription,
+                               MatchState matchState, bool verbose) {
+    var matcher = matchState.state['matcher'];
+    mismatchDescription.addDescriptionOf(matcher).add(' ');
+        matcher.describeMismatch(item, mismatchDescription,
+            matchState.state['state'], verbose);
     return mismatchDescription;
   }
 
   Description describe(Description description) =>
       description.addAll('(', ' and ', ')', _matchers);
 }
 
 /**
  * Matches if any of the given matchers evaluate to true. The
  * arguments can be a set of matchers as separate parameters
@@ skipping 49 matching lines @@
     }
     return new _AnyOf(matchers);
   }
 }
 
 class _AnyOf extends BaseMatcher {
   final Iterable<Matcher> _matchers;
 
   const _AnyOf(this._matchers);
 
-  bool matches(item) {
+  bool matches(item, MatchState matchState) {
      for (var matcher in _matchers) {
-       if (matcher.matches(item)) {
+       if (matcher.matches(item, matchState)) {
          return true;
        }
      }
      return false;
   }
 
   Description describe(Description description) =>
     description.addAll('(', ' or ', ')', _matchers);
 }