React-hot-loader: ReferenceError: firstCurrentHook is not defined

[ahutchings]

I am experiencing a ReferenceError with react-hot-loader:

ReferenceError: firstCurrentHook is not defined
    at Object.hotCleanupHooks [as hotCleanup] (http://localhost:3000/scripts/vendor.js:277033:20)
    at cleanupReact (http://localhost:3000/scripts/vendor.js:280427:14)
    at reconcileHotReplacement (http://localhost:3000/scripts/vendor.js:280888:3)
    at renderReconciler (http://localhost:3000/scripts/vendor.js:280902:7)
    at Object.asyncReconciledRender [as componentWillRender] (http://localhost:3000/scripts/vendor.js:280910:3)
    at AppContainer.hotComponentUpdate (http://localhost:3000/scripts/vendor.js:279651:19)
    at AppContainer.render (http://localhost:3000/scripts/vendor.js:281128:12)
    at finishClassComponent (http://localhost:3000/scripts/vendor.js:268892:33)
    at updateClassComponent (http://localhost:3000/scripts/vendor.js:268860:12)
    at beginWork (http://localhost:3000/scripts/vendor.js:269485:16)
    at performUnitOfWork (http://localhost:3000/scripts/vendor.js:272317:16)
    at workLoop (http://localhost:3000/scripts/vendor.js:272346:26)
    at renderRoot (http://localhost:3000/scripts/vendor.js:272377:9)
    at performWorkOnRoot (http://localhost:3000/scripts/vendor.js:272952:24)
    at performWork (http://localhost:3000/scripts/vendor.js:272873:9)
    at performSyncWork (http://localhost:3000/scripts/vendor.js:272850:5)

Environment

React Hot Loader version: 4.7.2

Run these commands in the project folder and fill in their results:

1. node -v: v11.9.0
2. npm -v: 6.8.0

Then, specify:

1. Operating system: macOS 10.13.3
2. Browser and version: Chrome 72.0.3626.121

Reproducible Demo

I'll create a demo if needed. However, I suspect this is because I'm using versions of react and react-dom (16.3.2) that don't include hooks, and so don't define the hook-related variables that are cleaned up by react-hot-loader. Please let me know if I can provide more information or if you need a demo in order to diagnose this further.

[theKashey]

:( It's more about which React version you use

[theKashey]

Then - you dont need hot-patch - so disable webpack-loader for react-dom, or dont use hot-loader/react-dom, if you do.

[ahutchings]

Thanks for the quick reply. This incompatibility needs to be expressed somewhere. Does the overall project still support React 16.3?

If yes, then we probably just need a note in the documentation that the webpack plugin only supports react and react-dom 16.8.0 and above.
If no, then the peerDependencies in package.json need an update, which would be a breaking change and require a major version bump for react-hot-loader.

Let me know what you'd like to do and I can try to put a PR together.

[theKashey]

We still maintain tests and compatibility with React 15, but sometimes something could go wrong, as long the main problem is to support new features.

excluding react-dom from webpack-loader is a one line in webpack configuration, and would help you __here and now__. Later I would fix webpack-loader not to break your app, but that would be not today.

[Taraluktus]

Not sure if it's the version as we're seeing it also with React 16.8.4 and all other packages (RHL, Webpack etc.) up-to-date

[theKashey]

👍 breaks with 16.8.4. Last tested version is 16.8.3 👍

[theKashey]

[email protected] (or hot-loader/[email protected]) released

[ahutchings]

Thanks @theKashey! I tested 4.8.0 against react & [email protected] and confirmed those versions are working again, so I think this issue can be closed.

[theKashey]

Thanks for reporting an issue in a right time :)