block12.jsx

class Cloning_ extends React.Component {
  render() {
    console.log('Cloning Render')

    const { children, ...propsToPass } = this.props
    const child = React.Children.only(children)

    console.log('passProps', propsToPass)

    return React.cloneElement(child, propsToPass)
  }
}

class PureComponent extends React.PureComponent {
  render() {
    console.log('PureComponent Render')
    return (
      <div />
    )
  }
}

export default class App extends React.Component {
  state = {}

  componentDidMount() {
    setTimeout(() => this.setState({hi: 'hi'}), 2000)
  }

  render() {
    return (
      <Cloning_ hi='hi'>
        <PureComponent />
      </Cloning_>
    )
  }
}