Some modules labeled 'esm' are dual about npm-esm-vs-cjs HOT 2 OPEN

Heya Joyee! Thanks!

I guess it’s the import for ESM and then a default condition for CJS. Feels a bit weird to do it that way instead of the inverse, or instead of the require vs import mutually exclusive conditions.

Did you find more?
I’ll investigate next time I crawl. Or, PR welcome!

from npm-esm-vs-cjs.

I guess it’s the import for ESM and then a default condition for CJS.

Yes, this seems quite common actually. Also many of them have "type": "module" at the top level package.json, but also another package.json in a folder that has "type": "commonjs", and then in the top level package.json they have conditional exports require or default pointing to that folder (axios, parse5, html-escaper, etc.). Some of them have "type": "module" but then the files resolved via main or exports have .cjs extension (e.g. marked) so could also be loaded just fine as CJS.

I've put the ones I've found (and the script used to load them with require()) in https://github.com/joyeecheung/test-require-esm/blob/main/dual.cjs

from npm-esm-vs-cjs.