Recursive prop-types (menu-like)

item.js

import { func, node, oneOf, oneOfType, shape, string } from 'prop-types';

import items from './items';

export const item = {
  id: string.isRequired,
  children: node.isRequired,
  url: oneOfType([string, func]),
  target: oneOf(['_blank']),
};

export default function() {
  return shape({ ...item, items }).apply(this, arguments);
}

items.js

import { arrayOf } from 'prop-types';

import item from './item';

export default function() {
  return arrayOf(item).apply(this, arguments);
}

Updated:

item.js

import { bool, func, node, oneOfType, string } from 'prop-types';

import { propTypes as items } from '../items';

export const propTypes = {
  label: node.isRequired,
  url: oneOfType([func, string]),
  fragment: string,
  active: bool,
  exact: bool,
  disabled: bool,
  items: function() {
    return items.apply(this, arguments);
  },
};

items.js

import { arrayOf, shape } from 'prop-types';

import { propTypes as item } from '../item';

export const propTypes = function() {
  return arrayOf(shape(item)).apply(this, arguments);
};