deepClone clarification questions & documentation

[ErikGro]

Hello,

thanks for open sourcing this awesome library!
I used deepClone for creating a new proxy of an existing proxy (not resetting) and I experienced some unexpected behaviour (from my perspective!).

Unexpected was, that it returns proxies for sets and maps for nested properties but the clone object itself is not a proxy. I expected that the clone object is as well a proxy.
Secondly, when deep cloning proxies containing nested js Date instances, they were not copied - which makes sense from a technical view but might be unexpected from an application developer view.

[overthemike]

Yeah - this is a good point. We made a change to deepClone a little while back to be proxyMap/proxySet aware as it was causing other issues (#1072). What's going on here is that maps and sets are not able to be tracked via proxy in JS, so we created proxyMap and proxySet that work in the same way, but allow us to track data changes within. deepClone is modifying maps to proxyMaps and sets to proxySets, but it doesn't create a proxy for you. For your case, just pass the resulting object into proxy and everything fall into place.

const initialState = { ... }

const clonedState = deepCLone(initialState)
const store = proxy(clonedState)

@dai-shi - do you think this is something that is an issue or should deepClone stay this way as it's a valtio utility specifically....

[dai-shi]

I understand the confusion.
At the baseline, I don't want Valtio to export deepClone. People can use any util like lodash, and it should work for most of the cases.
deepClone was added so that the migration from v1 to v2 should be flawless.
Now, I'm not sure if #1074 was the right move. I think we should add deepProxy instead, but I'm not very sure.

[overthemike]

#1169

I went with your idea and added a deepProxy function that acts like clone but wraps everything in proxy() and converts maps/sets to their proxy counterparts.

[ErikGro]

If I find some time in october I may also offer some help with documentation & tests