mobx-react-lite@4.0.2 observer not triggering component re-renders

[johnsonsu]

The observer of mobx-react-lite seems to not trigger the wrapped component to re-renders after upgrading from mobx-react-lite@3.4.3 to mobx-react-lite@4.0.2.

Intended outcome:

When an observable value changes in the store, the observer component should re-render with the new value.

Actual outcome:

The observer component does not re-render when the observable value is updated.

How to reproduce the issue:

Code Sandbox: https://codesandbox.io/s/new-dawn-b2shxq?file=/src/App.js

Clicking "Push new element to data" button will push a new element to the store.data array using a store action.

However, the component does not re-render even thought store.data has been updated (see console logs).

If you change the mobx-react-lite version from 4.0.2 to 3.4.3 in the sandbox, the component will re-render when you click the "Push new element to data" button.

Versions

mobx-react-lite@4.0.2

[imjordanxd]

I've started using observer from mobx-react as a workaround also exists in mobx-react 8

[kenbankspeng]

@imjordanxd What version of mobx-react works for you? Because I think I'm seeing this same issue with mobx-react 8.0.0.

[kenbankspeng]

The sandbox provided in the issue also fails using the observer from mobx-react 8.0.0 but works using mobx-react 7.6.0. No doubt same root cause as in mobx-react-lite@4.0.2.

[hheimerd]

If you turn off StrictMode, then the update works.
I also found this bug on the 8th version of mobx-react

[hheimerd]

I noticed that the update is working with strict mode, but only in the Production build. Most likely the problem with compatibility with the DEV mode in React

Working configuration:

"mobx": "^6.7.0",
"mobx-react": "^7.6.0"

non -working configuration:

"mobx": "^6.7.0",
"mobx-react": "^8.0.0",

[urugator]

I identified the cause, but the fix seems to be non-trivial atm. The problem can also appear outside StrictMode (probably only when using concurrent features or when FinalizationRegistry isn't available), WIP PR #3673

[mweststrate]

@urugator should we unpublish this major mobx-react / mobx-react-lite to avoid people taking it in production unawares until fixed?

[urugator]

@mweststrate Yea, probably. Atm I can provide a "fix", where everything basically works, bot not as intended - it won't use a global state version - however it's actually NOT using global version even now, because there was a pretty stupid typo:
https://github.com/mobxjs/mobx/pull/3673/files#diff-6b93715e19eb9119588dbe2af609a132062e61484d0d3de41b9e32e2d4a4ad5cL30-R30
And turned out switching to global version for some reason breaks interoperability with mobx-react or class components in general, dunno, have to investigate further, probably not sooner than over the weekend.

[urugator]

Found the problem - observable state/props/context setters increment global state version during render. Don't know about a solution yet.

[evoyy]

mobx-react v8.0.0 broke my apps. I wrap my app in StrictMode in development. If I remove StrictMode, it all works again. I already pushed another app to production but StrictMode is disabled in production so I dodged a bullet there.

[mweststrate]

Yeah will unpublished when I'm behind a keyboard again

…

On Wed, 29 Mar 2023, 02:08 evoyy, ***@***.***> wrote: mobx-react v8.0.0 broke my apps. I wrap my app in StrictMode in development. If I remove StrictMode, it all works again. I already pushed another app to production but StrictMode is disabled in production so I dodged a bullet there. — Reply to this email directly, view it on GitHub <#3671 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAN4NBC7TGYAN7QXVSB7DTTW6N4RFANCNFSM6AAAAAAWJZWIM4> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[mweststrate]

Reverted latest tag back to mobx-react@7.6.0 / mobx-react-lite@3.4.3, and deprecated the newer majors.

[LoveMeWithoutAll]

Has this issue been resolved? I'm waiting so long.

[mweststrate]

We reverted the 4.x release, we'll release it again, but needs some more time. For now stick to 3.x

…

On Wed, 26 Apr 2023, 09:33 YoungSeon.Ahn, ***@***.***> wrote: Has this issue been resolved? I'm waiting so long. — Reply to this email directly, view it on GitHub <#3671 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAN4NBEX2FUD6RWMYHFVOUTXDDFUXANCNFSM6AAAAAAWJZWIM4> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[mweststrate]

Should be fixed by mobx-react@9. Thanks for the patience!

[DeepakM02]

is it fixed? @mweststrate in mobx-react-lite?

[wuzinong]

Is it fixed?

[kubk]

@wuzinong Feel free to create a separate issue with a reproduction. No need to bump old issues