useIsomorphicLayoutEffect flag set wrongly

What is the current behavior?

useIsomorphicLayoutEffect is set to true when running on a Node.js instance, where the window object is defined.

This is a common scenario when you need to emulate a subset of a web browser for tests or DOM manipulation, then you define the object perhaps with JSDom.

It’s resulting in console warnings and issues when hydrating the SSR code.

What is the expected behavior?

useIsomorphicLayoutEffect flag is set to false when running in Node.js, always, not relying only on the window object being undefined.

Ref: https://github.com/reduxjs/react-redux/blob/master/src/utils/useIsomorphicLayoutEffect.js#L12

Used versions

react@16.8.4
react-redux@7.1.3

This used to work without issues, in react-redux@6.0.0.

[timdorr]

If you’re defining window as a global, that’s going to potentially affect a large number of libs, not just React Redux. I don’t think what you’re doing is the “correct” way of creating a virtual DOM for your libraries.

Over time, JSDOM is going to get closer and closer to the DOM spec, so things like the innerWidth value you’ve chosen will be implemented and fail as a check for our library. My biggest concern here is getting in an “arms race” over JSDOM’s spec implementation and our detection code. That is a losing battle for us, long term.

Is it reasonable to make your code not rely on window being global? Can you create a window instance in a module that will ponyfill where it’s needed? That seems more sensible for your codebase anyways, and less likely to cause problems elsewhere.

[markerikson]

It’s sad just how specific we’re having to feature-detect this.

Yeah, can you file a PR to add that change here?