Publish `exports` and `imports` implementations as separate module(s)

What is the problem this feature will solve?

Projects implementing support for module resolution have to add support for the quite advanced exports and imports fields in package.json.

https://nodejs.org/api/packages.html#exports
https://nodejs.org/api/packages.html#imports

Examples of projects that have done this are Webpack, TypeScript, Jest (only exports, not imports), Yarn and probably more. AFAIK neither Rollup, Parcel or Metro (to name some bundlers) have support.

What is the feature you are proposing to solve the problem?

If the algorithm Node uses internally was published as a separate module, I hope (and believe) more projects would be able to add support more readily, and that ecosystem compatibility would improve as a result.

I think part of the reason is the complexity in supporting the algorithm needed, particularly with subpath exports, wildcards and conditionals. E.g. https://github.com/browserify/resolve/issues/222 is stuck, and https://github.com/facebook/jest/issues/9771 took a long time.

Prior art for externalizing parts of Node publishing cjs-module-lexer separately, which means Jest could implement the same feature as node itself when importing CJS from ESM (via vm API).

Note that this is not a request for the full require or ESM resolution algorithm. This is solely a request for "given this exports/imports, this specifier and these conditions, what path does it map to" - no FS access/lookups at all. API similar to https://github.com/lukeed/resolve.exports makes sense to me.

What alternatives have you considered?

Jest (and Yarn) currently use https://github.com/lukeed/resolve.exports to avoid having to implement all the resolution. It currently does not support imports (https://github.com/lukeed/resolve.exports/issues/14).

リンクされた package exports と imports に関する Node.js ドキュメントから始め、次に引用されている resolve.exports モジュールと関連する例を比較します。ファイルシステムにアクセスせずに specifier と conditions をマッピングするスタンドアロン実装の範囲を定義します。完了条件は、提案するモジュールが exports と imports を対象としつつ、完全な require または ESM の解決とは分離されていることです。