package.json exports and types are not compatible with TypeScript's node16 moduleResolution

[AlCalzone]

Description

TypeScript added a new module resolution strategy node16 that better mimicks Node.js. Only under this option (or nodenext) is the exports field evaluated.

When authoring a .ts file in a CommonJS project and using this import

import rateLimit from 'express-rate-limit'

TypeScript complains about trying to require an ES module from CommonJS. This is because there's only one .d.ts file for both the CJS and ESM entrypoint and TypeScript considers that to be ESM due to the nearest package.json.
https://www.typescriptlang.org/docs/handbook/esm-node.html#packagejson-exports-imports-and-self-referencing mentions at the bottom that each needs their own declaration file.

As awkward as this is, this can be fixed by

1. renaming index.d.ts to index.d.mts
2. copying index.d.mts to index.d.cts
3. changing the package.json exports like this:

	"exports": {
		".": {
			"import": {
				"types": "./dist/index.d.mts",
				"default": "./dist/index.mjs"
			},
			"require": {
				"types": "./dist/index.d.cts",
				"default": "./dist/index.cjs"
			}
		}
	},

Library version

6.7.0

Node version

16.20.0

Typescript version (if you are using it)

5.1.6

Module system

CommonJS

[gamemaker1]

Hi @AlCalzone,

Thanks for detailing the issue and the solution so nicely :)

I'll make a PR for this once I get to a computer, unless you want to take a crack at it?

Regards,
Vedant