SB5 Theming breaks React 15 compat

[shilman]

The problem

Currently theming operates in config.js which is "preview" code (user code). It requires Emotion, which in turn requires React 16.3+.

In 5.0.x the workaround is to not theme Storybook.

This breaks in 5.1.x, probably due to #6435

I've created an example and added it to the repo so we can discuss around it, and also to make sure we don't inadvertently break back-compat in the future. Coming in a PR shortly.

The solution

Allow users to configure the manager separately from the preview, as relates to #4796 #4995

• split out create into its own file
• update documentation

[tmeasday]

There is another solution which I suggested somewhere else and which seems to have dropped off the map: rearrange @storybook/theming so the bit that you import for config.js doesn't import from emotion.

This doesn't seem at all hard to do, I had just asked @ndelangen some question about the animation stuff but he hadn't responded. I can take a look at it if we clear that up (that's the file that imports emotion and I'm pretty sure its only needed manager-side)

[ndelangen]

Should be fixed in this PR:
#6475

[ndelangen]

Thanks for the repro branch @shilman !

[shilman]

Yowza!! I just released https://github.com/storybooks/storybook/releases/tag/v5.1.0-alpha.40 containing PR #6475 that references this issue. Upgrade today to try it out!

Because it's a pre-release you can find it on the @next NPM tag.

Closing this issue. Please re-open if you think there's still more to do.

[natocTo]

I have tried it and still get same error.

TypeError: Object(...) is not a function

problem is here: (core.browser.esm.js)

var EmotionCacheContext = createContext(createCache());

There is problem with two versions of React. I use React 15 and Emotion use React 16. Import createContext from React 15 is resolved as undefined so it can not be call as function.

[mundosk8]

Im facing the same problem also. Even using the next tag

[ndelangen]

@shilman do you know how to reproduce this?

[shilman]

This issue seems like it hasn't gotten much action lately. Closing, please shout if you're still stuck on this!