naive React v15 pure functional component

pure.js

import React from 'react';

const pureMap = new WeakMap();

function makeComponent(fn, compare) {
    return class Memo extends React.Component {
        shouldComponentUpdate(nextProps) {
            return compare(this.props, nextProps);
        }
        render() {
            return fn(this.props);
        }
    };
}

function makePureComponent(fn) {
    return class Memo extends React.Component {
        render() {
            return fn(this.props);
        }
    };
}

function makePure(fn, compare) {
    const { propTypes } = fn;
    const component = typeof compare === 'function'
        ? makeComponent(fn, compare)
        : makePureComponent(fn);
    Object.defineProperty(component, 'name', { value: `Memo(${fn.name})` });
    if (propTypes !== undefined) {
        component.propTypes = propTypes;
    }
    return component;
}

export function pure(fn, compare) {
    if (!pureMap.has(fn)) {
        pureMap.set(fn, makePure(fn, compare));
    }
    return pureMap.get(fn);
}

Usage

import React from 'react';
import PropTypes from 'prop-types';
import { pure } from './pure';

function MyComponent(props){
    return <h1>{props.title}</h1>;
}

MyComponent.propTypes = {
    title: PropTypes.string
}

export default pure(MyComponent);