Dynamically importing date-fns locales other than en-US fail

[mikeesto]

Requirements

• This is a bug report, and if not, please post to https://lemmy.ml/c/lemmy_support instead.
• Please check to see if this issue already exists.
• It's a single bug. Do not report multiple bugs in one issue.
• It's a frontend issue, not a backend issue; Otherwise please create an issue on the backend repo instead.

Summary

lemmy-ui/src/shared/utils/app/setup-date-fns.ts

Lines 10 to 15 in dd43827

	const locale = (
	await import(
	/* webpackExclude: /\.js\.flow$/ */
	`date-fns/locale/${lang}`
	)
	).default;

If a user's browser is set to prefer something other than en-US, for example en-GB, then this import fails with the following error:

Steps to Reproduce

1. Use a browser that has a preferred locale to something other than en-US; or
2. Manually change lang to en-GB or another locale supported by date-fns

Technical Details

Chrome, running lemmy locally

Lemmy Instance Version

0.18

Lemmy Instance URL

No response

[alectrocute]

@jsit @SleeplessOne1917 We should remove date-fns entirely, especially since the timezone support is totally borked.

[SleeplessOne1917]

Should we go back to using Moment? Also, @alectrocute wasn't there an NPM library you shared in the dev matrix room that looked like a promising fix?

[alectrocute]

Yeah, @SleeplessOne1917, the date-fns-tz project. We should probably go back to using moment.js and switch the libraries again in the future in a separate branch where we can do thorough testing. 😌

[dessalines]

Is this one still an issue? Or did the above PR fix it?

[alectrocute]

Still an issue, a big one.

[sunaurus]

@alectrocute how to reproduce? It's importing for me without issues now

[alectrocute]

@sunaurus

• Go to a production instance, eg. https://voyager.lemmy.ml.
• Change language in user settings.
• Observe app break and error in console.

[sunaurus]

Can't reproduce, are you sure you're not getting an older cached client.js?

[alectrocute]

Resolved in 0.18.1-rc.4.