Function logger

packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js:448–454

(msg)

  it('should call nested legacy lifecycle methods in the right order', async () => {
    let log;
    const logger = function (msg) {
      return function () {
        // return true for shouldComponentUpdate
        log.push(msg);
        return true;
      };
    };
    class Outer extends React.Component {
      UNSAFE_componentWillMount = logger('outer componentWillMount');
      componentDidMount = logger('outer componentDidMount');