anchor.diff:    ///
     /// __Example use__:
     ///     ngTestBed = ngTestBed.addProviders([
  -  ///       const Provide(Foo, useClass: StubFoo),
  +  ///       const Provider(Foo, useClass: StubFoo),
     ///     ])
     NgTestBed<T> addProviders(Iterable<Object> providers) {
       return fork(providers: _concat(_providers, providers));
  
positive.code: ///       test('should render "Hello World", () async {
  ///         var bed = new NgTestBed<HelloWorldComponent>();
  ///         var fixture = await bed.create();
  ///         expect(controller, containsText('Hello World'));
  ///       });
  ///     });
  ///
  
negative.code: ///
  ///       test('should render "Hello World", () async {
  ///         fixture = await bed.create();
  ///         expect(fixture.text, contains('Hello World'));
  ///       });
  ///
  ///       test('should render "Hello World" in all-caps', () async {
  