React Custom PropType Validator - https://github.com/facebook/react/issues/9125#issuecomment-285531461

customPropType.isRequired.js

// Andrew Clark's explanation: https://github.com/facebook/react/issues/9125#issuecomment-285531461
// ---
// Checking for isRequired on custom validator
// PropTypes source: https://github.com/facebook/prop-types/blob/master/factoryWithTypeCheckers.js#L206-L217
// -------------------------------------------------------------------------------------------------------
// This is a factory function (also called a higher-order function)
function createCustomPropType(isRequired) {
  // The factory returns a custom prop type
  return function(props, propName, componentName) {
    const prop = props[propName];
    if (prop == null) {
      // Prop is missing
      if (isRequired) {
        // Prop is required but wasn't specified. Throw an error.
        throw new Error();
      }
      // Prop is optional. Do nothing.
    } else {
      // Put your validation logic here...
    }
  }
}

// Using the factory, create two different versions of your prop type
const customPropType = createCustomPropType(false);
customPropType.isRequired = createCustomPropType(true);

// Now this will work:
MyComponent.propTypes = {
  optional: customPropType,
  required: customPropType.isRequired,
};

customPropType.js

import React from 'react';
import PropTypes from 'prop-types';
 
class MyComponent extends React.Component {
  render() {
    // ... do things with the props
  }
}
 
MyComponent.propTypes = {
  // You can also specify a custom validator. It should return an Error
  // object if the validation fails. Don't `console.warn` or throw, as this
  // won't work inside `oneOfType`.
  customProp: function(props, propName, componentName) {
    if (!/matchme/.test(props[propName])) {
      return new Error(
        'Invalid prop `' + propName + '` supplied to' +
        ' `' + componentName + '`. Validation failed.'
      );
    }
  }
};