feature request: dirname & co

[nlambert]

Howdy! The documentation was clear, but I realize I inferred a bit too much from the plugin name and expected everything under import.meta to be transpiled.

Node.js has extended import.meta with properties like dirname as outlined here:

• import.meta
  • import.meta.dirname
  • import.meta.filename
  • import.meta.url
  • import.meta.resolve(specifier)

And for browsers I think the properties are just url and resolve.

Babel and this plugin seem like the best way to keep ES code and CJS hack free.

I’m not sure about the feasibility, but I wonder if it’s possible for the plugin to transpile each of these properties. Thanks for all the work you put into this plugin!

[javiertury]

It looks doable and I am open to PRs (with tests). The implementation seems straightforward

• import.meta.dirname: Alias for __dirname
• import.meta.filename: Alias for __filename
• import.meta.resolve: In CommonJs, it wraps global require.resolve() with url.pathToFileURL(). In ES6, it seems equivalent to

import { createRequire } from 'module';
import url from 'url';

const require = createRequire(url.pathToFileURL(__filename).toString());
const output = url.pathToFileURL(require.resolve('<input specifier>'));

However I won't have time to code it myself.

[javiertury]

The branch new_meta_apis is a quick draft for the desired functionality. If someone is really interested in those apis, they could work on a PR starting from that branch. To make it production ready, someone should make sure that the transformed output makes sense and complies with the import.meta specifications, test coverage should increase and documentation should be updated.