Export CreateObservableOptions type

[ahoisl]

Code change checklist

• IMO unnecessary - Added/updated unit tests
• IMO unnecessary - Updated /docs. For new functionality, at least API.md should be updated
• Verified that there is no significant performance drop (npm run perf)

Fixes issue #2716

[changeset-bot]

🦋 Changeset detected

Latest commit: d47b5f3

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[danielkcz]

Thanks for your contribution. Please add the changeset as per the comment above.

[urugator]

CreateObservableOptions defines undocumented fields that shouldn't be relied on.

[ahoisl]

CreateObservableOptions defines undocumented fields that shouldn't be relied on.

Sorry, I don't really understand. The options are documented here, so what do you mean by "undocumented"?
https://mobx.js.org/observable-state.html#options-

These are the default options used by makeObservable - are we talking about different things?

[urugator]

mobx/packages/mobx/src/api/observable.ts

Lines 39 to 46 in 3980787

	export type CreateObservableOptions = {
	name?: string
	equals?: IEqualsComparer<any>
	deep?: boolean
	defaultDecorator?: Annotation
	proxy?: boolean
	autoBind?: boolean
	}

defaultDecorator, equals, proxy shouldn't be part of the public API

[ahoisl]

@urugator That's a different problem then in my opinion, because these options already are part of the public API. If you use makeObservable (or makeAutoObservable), the will already show up as valid options. We probably need a sub-type then? That would be a breaking change to the API, though, to my understanding.

[urugator]

@mweststrate what's the intention/reasoning here?
equals is only used by observable.box ...
proxy seems to be used only by (2) tests (to force non-proxy impl)
defaultDecorator doesn't seem to be used at all, perhaps backward compatibility?

[mweststrate]

@urugator equals and defaultDecorator are internally be used by .struct, .ref and .shallow? If not I think it has been accidentally left there by a past cleanup. proxy should definitinely be documented and is an omission of mine in https://mobx.js.org/observable-state.html#options-; it is pretty useful as it allows you to skip using Proxies if the object shape is stable, which is (probably) faster, compatible with IE and a lot debug friendlier (it is still a shame debuggers don't treat proxies nicer).

[mweststrate]

see also: https://mobx.js.org/observable-state.html#avoid-proxies

[ahoisl]

@urugator I don't think I can do much more for the issue with the probably "left-over" props in the options equals and defaultDecorator. In any way, people could have already used those options and as I understand it, they would have an impact for some cases. So changing or removing the props would be a breaking change.

As these props are already public and exporting the CreateObservableOptions does not make a difference in regards to these props already being public/exported, can we close this PR and handle the props in a separate issue (if necessary)?

[mweststrate]

I think it is fine to merge this