anchor.diff:  
   class Expect {
     var actual;
  -  Expect(this.actual);
  +  var not;
  +  Expect(this.actual) {
  +    not = new NotExpect(this);
  +  }
   
     toEqual(expected) => unit.expect(actual, unit.equals(expected));
     toBe(expected) => unit.expect(actual,
  -      unit.predicate((actual) => identical(expected, actual)));
  +      unit.predicate((actual) => identical(expected, actual), '$expected'));
     toThrow(exception) => unit.expect(actual, unit.throwsA(unit.contains(exception)));
  -  toBeFalsy() => unit.expect(actual, unit.isFalse);
  -  toBeTruthy() => unit.expect(actual, unit.isTrue);
  +  toBeFalsy() => unit.expect(actual, (v) => v is bool ? v == false : !(v is Object));
  +  toBeTruthy() => unit.expect(actual, (v) => v is bool ? v == true : v is Object);
  +  toBeDefined() => unit.expect(actual, (v) => v is Object);
     toBeNull() => unit.expect(actual, unit.isNull);
     toBeNotNull() => unit.expect(actual, unit.isNotNull);
  +
  +  toHaveBeenCalled() => unit.expect(actual.called, true, reason: 'method not called');
  +  toHaveBeenCalledOnce() => unit.expect(actual.count, 1, reason: 'method invoked ${actual.count} expected once');
  +}
  +
  +class NotExpect {
  +  Expect expect;
  +  get actual => expect.actual;
  +  NotExpect(this.expect);
  +
  +  toHaveBeenCalled() => unit.expect(actual.called, false, reason: 'method called');
  +  toThrow() => actual();
   }
   
   $(selector) {
  
positive.code: import 'package:angular/debug.dart';
  import 'dart:mirrors' as mirror;
  import 'package:angular/angular.dart';
  import 'package:di/di.dart';
  
  export 'package:unittest/unittest.dart';
  export 'package:angular/debug.dart';
  
negative.code: export 'dart:html';
  export 'jasmine_syntax.dart';
  export 'package:di/di.dart';
  export 'package:unittest/mock.dart';
  
  es(String html) {
    var div = new DivElement();
  