React.memo and React.lazy ignore propTypes

Do you want to request a feature or report a bug? Bug

What is the current behavior? PropTypes.*.isRequired with React.memo doesn’t get triggered in the console when the required prop is undefined.

import React, { memo } from "react";
import ReactDOM from "react-dom";
import PropTypes from "prop-types";

// ********************************************
// It should appear two propTypes console errors
// ********************************************

// without memo(..): it will throw the propTypes error like it should
const MemoButton = memo(() => {
  return <button>Memo Button</button>;
});
MemoButton.propTypes = {
  memocolor: PropTypes.string.isRequired
};

// it will throw the error in the console
const Button = () => {
  return <button>Button</button>;
};
Button.propTypes = {
  color: PropTypes.string.isRequired
};

const rootElement = document.getElementById("root");
ReactDOM.render(
  <>
    <MemoButton />
    <Button />
  </>,
  rootElement
);

Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?

// affected versions
"prop-types": "15.6.2",
"react": "16.6.1",
"react-dom": "16.6.1",

[gaearon]

This turned out to be harder than expected 😅 Fix in https://github.com/facebook/react/pull/14298.

[Jessidhia]

The update to use react-is is not yet @latest; the @latest release still uses PropTypes.func.

This is the current check on master: https://github.com/ReactTraining/react-router/blob/d5979813abcd53f7ab0e518248374c61c22f8e15/packages/react-router/modules/Route.js#L131-L137