Types entries missing in package exports (Needed for Typescript >= 4.7 and moduleResolution="Node16"/"Nodenext")

[gunters63]

🐛 Bug Report

types entries missing in package exports

To Reproduce

For projects using Typescript >= 4.7 AND Node resolution Node16/Nodenext the types fail to load with the message:

 Could not find a declaration file for module 'i18next-browser-languagedetector'

This can be reproduced with a minimal project using Typescript >= 4.7 and "moduleResolution": "Node16", in the tsconfig.json configuration file.

Expected behavior

Typescript types should load.

• runtime version: Node 18
• Typescript: 4.8.4
• i18next version: 21.10.0
• i18next-browser-languagedetector: 6.1.6
• os: Windows

The cause seems to be that the types property is missing from the module exports:

  "exports": {
    "./package.json": "./package.json",
    ".": {
      "require": "./dist/cjs/i18nextBrowserLanguageDetector.js",
      "default": "./dist/esm/i18nextBrowserLanguageDetector.js"
    },
    "./cjs": {
      "default": "./dist/cjs/i18nextBrowserLanguageDetector.js"
    },
    "./esm": {
      "default": "./dist/esm/i18nextBrowserLanguageDetector.js"
    }
  },

The correct ones would be:

  "exports": {
    "./package.json": "./package.json",
    ".": {
      "require": "./dist/cjs/i18nextBrowserLanguageDetector.js",
      "default": "./dist/esm/i18nextBrowserLanguageDetector.js",
      "types": "./index.d.ts"
    },
    "./cjs": {
      "default": "./dist/cjs/i18nextBrowserLanguageDetector.js",
      "types": "./index.d.ts"
    },
    "./esm": {
      "default": "./dist/esm/i18nextBrowserLanguageDetector.js",
      "types": "./index.d.ts"
    }
  },

The reason seems to be that the Typescript compiler (starting from 4.7) uses the exports fields to find the type declaration files and there is no fall back to the package.json "types" property when they are missing.

See also: https://devblogs.microsoft.com/typescript/announcing-typescript-4-7/#esm-nodejs

[adrai]

Would you like to send a Pull Request to address this?

[adrai]

just released v6.1.7

[gunters63]

That fixed the problem! Thanks :)

[adrai]

https://github.com/i18next/i18next-browser-languageDetector/issues/267

[gunters63]

Yes, sorry. Missed that before.

The types entry should be the first one in the exports.

[gunters63]

When I hacked directly in the package.json it worked, but other tools insist on the correct order I suppose :)