Production build each propType is same instance of shim

[AndyOGo]

We use this propTypes for custom elements to make runtime parsing based upon prop-types.

Unfortunately in Production the following is true:

import PropTypes from 'prop-types';

PropTypes.string === PropTypes.bool === PropTypes.number === PropTypes.array === PropTypes.object
// -> true

Though this should be false.

Currently the shim function is static, It would be better to generate it or use a shim factory. https://github.com/facebook/prop-types/blob/master/factoryWithThrowingShims.js#L15-L59

[ljharb]

See #106.

[AndyOGo]

Thanks for your immediate feedback.

@gaearon @ljharb @sophiebits I really hope that you give me a chance to alter your decision and viewpoint about this topic.

If we combine your great approach and this PR we can get both benefits of both worlds - better stripped down production code or dev-only code and if someone like me or others have the crazy idea to use awesome prop-types for type casting stuff with custom elememt's attributes or whatever. Plus we have 100% consistent types/pureness between dev and prod. ATM this is not consistent and purity is lost, at dev all PropTypes functions are unique and at prod they are equal.

I would also argue since you decided to make prop-types it's own package, one of it's intention was to see wider utilization, which comes naturally with more use cases and support for other needs.

What do you think?

[AndyOGo]

@sophiebits @gaearon I'm sure you have lots of stuff on your todo-list.

I'm really convinced that you do a great job. Though I'm sure you allowed yourself a little mistake here and I would really insist and appeal to you to correct it. And follow your really nice purity, consistency attitude I know well from other projects of yours.

Hope we can settle this quickly.

[AndyOGo]

Just in case anyone else has this issue, you don't need to fork prop-types.

import PropTypes from 'prop-types';

// guard for Uncaught RangeError: Maximum call stack size exceeded in prod
let level = 0;

// @todo remove as soon as https://github.com/facebook/prop-types/issues/231 is resolved
function getShim(propType) {
  function shim(...args) {
    return propType(...args);
  }

  if (level === 0) {
    level++; // eslint-disable-line no-plusplus
    // make sure to also shim `isRequired`, etc.
    Object.keys(propType)
      .map((key) => {
        shim[key] = propType[key];

        return key;
      })
      .reduce(shimKeys, shim);
    level--; // eslint-disable-line no-plusplus
  }

  return shim;
}

function shimKeys(propTypes, key) {
  const propType = propTypes[key];

  if (typeof propType === 'function') {
    propTypes[key] = getShim(propType);
  }

  return propTypes;
}

const ReactPropTypes = PropTypes;

Object.keys(ReactPropTypes).reduce(shimKeys, ReactPropTypes);

export default ReactPropTypes;

[ljharb]

Closing per https://github.com/facebook/prop-types/pull/106#issuecomment-398443259, but it's fine to continue discussion if there's anything new.