Broken ESM support

[sai-cb]

When this library is imported under node as ESM, named exports are broken.

Reproduction steps

This can be reproduced by creating these files:

demo.mjs:

import { Helmet } from 'react-helmet-async';

console.log(Helmet);

demo.cjs:

const { Helmet } = require('react-helmet-async');

console.log(Helmet);

And then running them:

• node demo.mjs
• node demo.cjs

Running the .mjs demo file leads to the following crash currently:

import { Helmet } from 'react-helmet-async';
         ^^^^^^
SyntaxError: Named export 'Helmet' not found. The requested module 'react-helmet-async' is a CommonJS module, which may not support all module.exports as named exports.
CommonJS modules can always be imported via the default export, for example using:

import pkg from 'react-helmet-async';
const { Helmet } = pkg;

Solution

This seems to be fixable by adding the currently missing exports key in package.json:

  "exports": {
    ".": {
      "types": "./lib/index.d.ts",
      "import": "./lib/index.esm.js",
      "require": "./lib/index.js"
    }
  },

This preserves CJS compatibility but fixes ESM support.

[sai-cb]

Looks like there is a PR for this:
#251

[staylor]

#260