anchor.diff:  foo() {
   }
   ''');
  -    expect(helper.functions['main'], isNotNull);
  -    expect(helper.functions['foo'], isNotNull);
  +    helper.assertHasFunction('main');
  +    helper.assertHasFunction('foo');
     });
   
     test('Class instantiation', () {
  
positive.code:   bar() {}
  }
  ''');
      expect(helper.methods['A.foo'], isNotNull);
      expect(helper.methods['A.bar'], isNull);
      expect(helper.methods['B.foo'], isNull);
      expect(helper.methods['B.bar'], isNull);
    });
  
    test('Method invocation on dynamic', () {
  
negative.code: class A {}
  class B {}
  ''');
      helper.assertHasInstantiatedClass('A');
      helper.assertNoInstantiatedClass('B');
    });
  
    test('Method invocation', () {
  