[luxon] Export validity helper types from the barrel - #75463

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• luxon (3.7) — on npm, on unpkg

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🔔 @CarsonF @peterblazejewicz — please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

Re-ping @CarsonF, @peterblazejewicz:

This PR has been out for over a week, yet I haven't seen any reviews.

Could someone please give it some attention? Thanks!

Sorry for the delay here.
What's your use case for using these types?
They were always meant to be private helpers (hence the leading underscore _util).

I can see how DateTime<Valid> is desired, but idk if it is worth this library exporting it. The main goal of doing it here, was to provide readability for those consuming these types.
You could still easily do

export type Valid = true;
// or
export type ValidDateTime = DateTime<true>;

FYI if you opted in to throw on invalid, you wouldn't have to worry about the validity conditions.

import { Settings } from 'luxon';

Settings.throwOnInvalid = true;

declare module 'luxon' {
  interface TSSettings {
    throwOnInvalid: true;
  }
}

// DateTime == DateTime<true>

You're right about Valid/Invalid. DateTime<true> already works, no need to export those.

DefaultValidity, CanBeInvalid, and IfValid are different: conditional types on TSSettings, not literals. You can rebuild them locally since TSSettings is public, but every package needing them has to reimplement all three. That's what the old _util deep import gave for free before #73292. throwOnInvalid only helps code that commits app-wide to throwing; it doesn't help a library that wants one helper working in both modes. The same generics show up on Interval, Duration, and Zone too, not just DateTime.

Happy to drop Valid/Invalid and trim the export to just those three.

Are you subclassing? what are some signatures that use these types?