[meta] fix "exports" for node 13.0-13.6

[ljharb]

engines.node explicitly says ">= 6", which includes node 13.0-13.6, which is broken without this change.

This came up because @babel/generator now depends on this package.

[jridgewell]

How is it broken? The docs say this is supported: https://nodejs.org/docs/latest-v13.x/api/esm.html#:~:text=main.js%22%0A%7D-,Conditional%20Exports,-%23

[JLHwung]

Conditional exports, first introduced in 13.2, were behind the flag --experimental-conditional-exports in Node 13.2 - 13.6: https://nodejs.org/docs/v13.6.0/api/esm.html#esm_conditional_exports The link you provided is the latest v13 doc.

[ljharb]

Yep - node 13.0-13.1 only supports the string form (which is a bug that those versions of node consider "exports" at all), and 13.2-13.6 only support "default" (13.7 added "require"). The string fallback should cover both (adding "default" to the object would cover 13.3-13.6 alone)

[jridgewell]

Ok. What's the urgency of this to release?

[ljharb]

I mean, I’d say low given that few people are using node 13.0-13.6, but I’d hope it would be a quick patch regardless?

[jridgewell]

Thanks! Released in v0.3.2.