Same as https://github.com/facebook/react/issues/10103, but for the server renderer. You can look at implementation in https://github.com/facebook/react/pull/11168 and do something very similar in `ReactPartialRenderer.js`.
render() {
          return null;
        }
      }
      const response = ReactDOMServer.renderToString(<NullComponent />);
      expect(response).toBe('');
    });
    
    it('should render composite components', () => {
      class Parent extends React.Component {
        render() {
          return (
            <div>
              <Child name="child" />
            </div>
          );
        }
      }
      class Child extends React.Component {