Fix <StrictMode> warnings

[BenoitClaveau]

Is it possible to replace componentWillReceiveProps because is deprecated to remove React 16+ warning.

[timdorr]

cWRP isn't deprecated until React 16.4. As of this moment, 16.3 isn't even out. We're looking at larger refactors around async stuff in React 17 in #890.

[BenoitClaveau]

cWRP seems to be depreacted.

[TrySound]

@BenoitClaveau Which version of react do you use? It shouldn't happen until 16.4.

[respectTheCode]

This started showing up after updating to react-native 0.54.0.

[respectTheCode]

downgrading to react 16.2.0 doesn't remove the warnings

[TrySound]

I guess the problem is react-native. AFAIK they published package with react alpha which had this problem. Try to downgrade it.

[BenoitClaveau]

under "react": "16.2.0",

[respectTheCode]

The warnings are coming from react-native so downgrading react isn't enough. react-native 0.53 with react 16.2.0 doesn't have the warnings

[TrySound]

Yes, I meant downgrade react-native.

[anonrig]

Downgrading shouldn't be the option, since the latest valid version of react-native does deprecated these functions. Is there a ETA on the change?

[catamphetamine]

getDerivedStateFromProps is easy enough using the react-lifecycles-compat thing which isn't a breaking change.
And context also has a non-breaking polyfill (though only for React 16 which would be a breaking change):
https://github.com/thejameskyle/create-react-context

[Hypnosphi]

@timdorr I would like to make a PR migrating react-redux to new lifecycles using react-lifecycles-compat because I don't want StrictMode to warn me about my Connected components. Does it make sense to you?

I'm surprised I have to mention it on this repo, but this React blogpost says that library authors don't have to wait until actual deprecation happens
https://reactjs.org/blog/2018/03/27/update-on-async-rendering.html

The primary purpose of the upcoming version 16.3 release is to enable open source project maintainers to update their libraries in advance of any deprecation warnings.

[gaearon]

Yes, the purpose of 16.3 was to let libraries start migrating before the deprecation warnings.

[catamphetamine]

@gaearon I also think it would make a lot of sense for you to include a link to create-react-context polyfill same as you did for react-lifecycles-compat because otherwise people don't even know that they can transition their libraries to the new context without breaking React 16 users (though breaking all older Reacts).
Specifically I had to google a lot until I accidentally came across that create-react-context polyfill thing. It would make life easier for a lot of component mainterners if you included that link as a sidenote in the announcement blog post.

UPD: Oh, actually, it was not you, it was "Brian Vaughn", ok.

[timdorr]

Updating the title to better reflect what this is about. I'll put up a failing PR in a sec that others can build off of.

Edit: Looks like we're on React 15 still. I'm updating things to Jest and then React 16. And then I'll get to this. Bikeshedding at maximum speed!

[timdorr]

OK, phew, got all that done. We're now on React 16, Jest, and react-test-renderer.

Here's a failing test: #918

[Hypnosphi]

@catamphetamine Looks like create-react-context can actually be used to support React 15 and below. One should just be carefull and always pass a singe child element to Provider and always return a single element from Consumer child function. See jamiebuilds/create-react-context#15

[jamiebuilds]

@Hypnosphi Yeah... create-react-context only polyfills React.createContext you are still limited to the rendering features of the versions of React you are compatible with.

[packetstracer]

has this fix been released? which version?
I'm using:

"react": "^16.3.2",
"react-redux": "^5.0.6",

and still getting the error in strict-mode.

For example:

componentWillReceiveProps: Please update the following components to use static getDerivedStateFromProps instead: Connect(ProfileHandlerHoc)

componentWillUpdate: Please update the following components to use componentDidUpdate instead: Connect(ProfileHandlerHoc)

[Hypnosphi]

@packetstracer #919 isn't merged yet

[markerikson]

@packetstracer : please update to React-Redux 5.0.7 first, and see if that fixes the issue for you.

[ritchieanesco]

i've updated to react-redux 5.0.7 and also getting the same warnings as @packetstracer

[packetstracer]

still throwing these errors after update

componentWillReceiveProps: Please update the following components to use static getDerivedStateFromProps instead: Connect(DemoSideBarNavContainer), Connect(LanguageSelectorContainer), Connect(ProfileHandlerHoc)

componentWillUpdate: Please update the following components to use componentDidUpdate instead: Connect(DemoSideBarNavContainer), Connect(LanguageSelectorContainer), Connect(ProfileHandlerHoc)

package.json content
"react-redux": "^5.0.7",

cat node_modules/react-redux/package.json

{
  "name": "react-redux",
  "version": "5.0.7",
  "description": "Official React bindings for Redux",

Any clue on what could be?

[timdorr]

Those aren't fixed in 5.0.7. We have an outstanding PR to fix them.

[slim-hmidi]

So what is the alternative to use until the PR was merged to fix the warnings?

[Hypnosphi]

@slim-hmidi are you building a library or an app? If the latter, you shouldn't need StrictMode for now

[slim-hmidi]

@Hypnosphi I'm building an application.

[daraclare]

Hey folks, any update on the PR being merged? Thanks!

[grzegorzjudas]

Anyone coming here with this problem, you can use react-redux@next with npm (resolved to 5.1.0-test.1 as of now).

[josephcsible]

Can this issue be reopened, since the commit that fixed it was reverted in 73691e5?

[timdorr]

Sure. Though either #995 or #1000 is going to solve it.

[brunolemos]

Now that #1000 was merged, please make sure it works with StrictMode as well before releasing! 🙌 cc @timdorr @markerikson

[markerikson]

Tbh, I haven't tried that part out yet myself... but go install react-redux@next and let us know!

Purely off the top of my head, it ought to be just fine. We no longer use cWRP or cWU at all.

[brunolemos]

Just tested 6.0.0-beta.2, it did fix the warnings! :) thanks.

Now it's just react-native left :P facebook/react-native#22186

[timdorr]

Clooooosing out!