Unexpected token: operator (?) in file node_modules/@storybook/preview-api/dist/preview-web.js. error

[SaiChand-Headout]

Describe the bug
error node_modules/@storybook/preview-api/dist/preview-web.js: Unexpected token: operator (?) in file node_modules/@storybook/preview-api/dist/preview-web.js at 3139:39. Getting this error when trying to build for iOS

To Reproduce
Steps to reproduce the behavior:
Run yarn
./node_modules/.bin/react-native bundle
--dev false
--platform ios
--reset-cache
--entry-file index.js
--bundle-output ./TEST_BUNDLE
--sourcemap-output ./TEST_BUNDLE.map in root folder with storybook version (7.6.20) and RN version (0.70.5)

Screenshots

[SaiChand-Headout]

@dannyhw i've seen a similar issue in storybook JS repo as well, but didn't see any resolution over there. Felt this is the right repo to track hence sharing here. #598 for reference

[dannyhw]

please can you share the version of react-native and storybook etc

[SaiChand-Headout]

I've shared it in the description, storybook version (7.6.20) and RN version (0.70.5) here are the versions i've used

[dannyhw]

Can you try updating react native or is that not an option?

But also can you verify that all storybook packages are on the same version?

[SaiChand-Headout]

Unfortunately no, we have an update scheduled by the end of year, we can do it only then

[dannyhw]

what about the versions of the different storybook packages are they all aligned?

[SaiChand-Headout]

Yes, they are all same

[SaiChand-Headout]

Sorry to bother you, any updates here ?

[dannyhw]

do you have a reproduction I can look at?

[SaiChand-Headout]

unfortunately, it's a private repo.. but you can try it out with https://github.com/esbenvb/storybook-rn-minify-issue this link, they were facing the same issue and the dependency versions are pretty much similar...

[dannyhw]

A reproduction is a minimal recreation of the problem in a public repo it doesn't require private code to be included.

[dannyhw]

I don't have a lot of time to look at it right now because of work and other commitments but i will try to check this weekend

[SaiChand-Headout]

Sure @dannyhw , any luck with this ??

[dannyhw]

so far I have just confirmed that by passing --minify false it does work, so the minify step is causing the issue. Still trying out different options to try and figure out what the issue is.

[dannyhw]

@SaiChand-Headout Ok I found the issue, there is a ??= that seems to cause the issue, if you add '@babel/plugin-transform-logical-assignment-operators' then it successfully minifies.

heres the changes needed: https://github.com/esbenvb/storybook-rn-minify-issue/pull/1/files

[ktml]

I had the same issue with react native 0.69.9, spent days trying to get storybook working on android.

@dannyhw's solution works perfectly. Thanks guys!

[SaiChand-Headout]

thanks a lot @dannyhw , this worked