content: // @flow
  
  import React from 'react';
  
  class MyComponent1 extends React.Component {
    componentWillReceiveProps(nextProps) {}
  }
  
  class MyComponent2 extends React.Component {
    shouldComponentUpdate(prevProps, prevState) {}
  }
  
  class MyComponent3 extends React.Component {
    componentWillUpdate(prevProps, prevState) {}
  }
  
  class MyComponent4 extends React.Component {
    componentDidUpdate(prevProps, prevState) {}
  }
  
  const expression1 = () =>
    class extends React.Component {
      componentWillReceiveProps(nextProps) {}
    }
  
  const expression2 = () =>
    class extends React.Component {
      shouldComponentUpdate(prevProps, prevState) {}
    }
  
  const expression3 = () =>
    class extends React.Component {
      componentWillUpdate(prevProps, prevState) {}
    }
  
  const expression4 = () =>
    class extends React.Component {
      componentDidUpdate(prevProps, prevState) {}
    }
  