👋 I tested these changes in the native version and unfortunately the built-in version of flatMap is not 100% supported (Android particularly).

Would it be possible to use the version from the lodash library instead? Do you foresee any inconvenience of using that version instead of the built-in?

Thanks!

Thanks for checking! 🙏

Using the lodash one instead should be fine, but I'm wondering whether our Babel config is intentionally leaving it unhandled. Could it have been an oversight in the v7 migration?

I'd think it would be safer if we relied on Babel to handle it, unless there's a project-wide preference to use lodash replacements for built-in functions. I'm not really familiar with the goings-on here though. Do you know?

(Noting one more instance, in case we're going the lodash route.)

Using the lodash one instead should be fine, but I'm wondering whether our Babel config is intentionally leaving it unhandled. Could it have been an oversight in the v7 migration?

To be honest I'm not sure, the adoption of built-in flatMap is quite high (91.18% as checked in caniuse.com) and since it has been only used in one place maybe we haven't spotted this issue yet.

(Noting one more instance, in case we're going the lodash route.)

Good catch! That part should be also incompatible with the native version but most likely it hasn't raised any issue because is not used (I need to check it).

I found interesting that this place was the only one where the built-in flatMap was being used so far, maybe as you commented, there's a project-wide preference to use lodash.
I'm not familiar neither with this since I'm working more in the native side but I'll ask for help.

The polyfills are included separate in WordPress in a wp-polyfill package. I think that package is probably not included in native, should it be included?

Yeah we would need to import and inject that package when generating the JS bundle for React native. Could you point me out where I can get that package? Thanks!

Its setup is a bit complex, it's mainly composed of babel-polypill see https://github.com/WordPress/wordpress-develop/blob/master/package.json#L81

but it has other dependencies that are only loaded if the browser doesn't support them https://github.com/WordPress/wordpress-develop/blob/master/src/wp-includes/script-loader.php#L122-L136

Thanks @youknowriad for the info!

I'm going to try adding the core-js dependency to the react-native-editor package (the entry point for the native version) and import the polyfill for flatMap from core-js/features/array/flat-map as states in the Babel documentation.

Finally I've included the polyfill by adding core-js to the native package in this PR. In the future if we need to add new polyfills we'll have an entry point there.

Thanks @mirka and @youknowriad for checking this!

Thanks for the quick fix @fluiddot 🙌