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Opening early to:

• Check what might not be working yet. For now there is[Feature]: add support for generator.dataUrl as a function in loader config web-infra-dev/rspack#5640, but it has been fixed (but not yet released)
• Check if this might help with faster builds on CI
• Check if this could help the Binder not go out of memory

Some first numbers runningjlpm build:dev:prod:release:

rspack

webpack

Hi@jtpio , how to migrate custom widget library with custom webpack.config.js?

• Use the default Rspackexperiments.css (set totrue by default), or keep the currentcss-loader,style-loader,mini-css-extract-plugin. Might needsupport mini-css-extract-plugin web-infra-dev/rspack#3210

Rspack 0.6.0 now supports it:https://www.rspack.dev/blog/announcing-0.6.html#built-in-support-for-mini-css-extract-plugin

@jtpio I want to join your work, should I continue contributing to the jupyterlab-rspack project?

Thanks@FoSuCloud!

https://github.com/jtpio/jupyterlab-rspack might be lagging a bit behind now. Maybe we could work on this PR directly instead? If you are able to open PRs against this branch I would be happy to merge your contributions.

There are still a few items listed in the top comment that we should check / re-enable, that can serve as a good starting point for continuing this work.

Thank you again for offering your help!

Hi@jtpio , how to migrate custom widget library with custom webpack.config.js?

@erkin98 for now this is not ready yet. But hopefully the customwebpack.config.js should still be compatible with Rspack (or we should make it possible to use the same config). Would you be able to share the config here or in#15035?

Looks like updating to theRspack 0.6.1 release introduces the following error in the dev tools console:

Looks like updating to theRspack 0.6.1 release introduces the following error in the dev tools console:

web-infra-dev/rspack#6230 this might be the same cause. Could you please try out the nightly version?

seems not help

the current nightly version0.6.1-canary-73a9832-20240414004901 should help

Thanks@xc2 for chiming in!

Also updating to the latest0.6.2 seems to be giving this issue:

../node_modules/@rspack/binding/binding.d.ts:36:47 - error TS2552: Cannot find name 'PathData'. Did you mean 'JsPathData'?36   getAssetPath(filename: string | ((pathData: PathData, assetInfo?: JsAssetInfo) => string), data: JsPathData): string                                                 ~~~~~~~~../node_modules/@rspack/binding/binding.d.ts:37:55 - error TS2552: Cannot find name 'PathData'. Did you mean 'JsPathData'?37   getAssetPathWithInfo(filename: string | ((pathData: PathData, assetInfo?: JsAssetInfo) => string), data: JsPathData): PathWithInfo                                                         ~~~~~~~~

Thanks@xc2 for chiming in!

Also updating to the latest0.6.2 seems to be giving this issue:

../node_modules/@rspack/binding/binding.d.ts:36:47 - error TS2552: Cannot find name 'PathData'. Did you mean 'JsPathData'?36   getAssetPath(filename: string | ((pathData: PathData, assetInfo?: JsAssetInfo) => string), data: JsPathData): string                                                 ~~~~~~~~../node_modules/@rspack/binding/binding.d.ts:37:55 - error TS2552: Cannot find name 'PathData'. Did you mean 'JsPathData'?37   getAssetPathWithInfo(filename: string | ((pathData: PathData, assetInfo?: JsAssetInfo) => string), data: JsPathData): PathWithInfo                                                         ~~~~~~~~

Thanks!

@ahabhgk fixes it inweb-infra-dev/rspack#6265

please try 0.6.2-canary-4b8f4a6-20240417094517

Fix Mathjax warnings:

I'm not seeing mathjax warnings in the current PR tests and when I manually dojlpm run build, so I'll mark this as done.@jtpio - if you see those mathjax warnings, let me know.

Fixed and testedjupyter lab --dev-mode --watch - the dev-mode watch was not getting the right config file.

licenses seems to work:jlpm build:dev:prod generates a reasonable-lookingdev_mode/static/third-party-licenses.json

Watch workflows we are targeting:

1. ✅jupyter lab --dev-mode --watch should pick up changes in core packages
2. ✅jlpm run watch in a prebuilt extension installed withlabextension develop rebuilds and serves the new prebuilt extension, reflecting changes after a frontend refresh

I think what we'll be missing islabextension link, which lets us install/watch asource extension - but those are deprecated at this point.

For reference a lot of the watching stuff was last touched in#6700

@jtpio - ready for review.

@krassowski,@jtpio - what do you think about merging this now and making a quick alpha of 4.6 so we can start getting feedback on how the build system works for the staging directory?

Oh wow, thanks@jasongrout for working on this and having all the checks finally pass!

Agreed that it would be better to merge this early in an alpha release, to have the full release cycle to better test it 👍

Let's add a note about this in theextension migration guide, for visibility?

Let's add a note about this in theextension migration guide, for visibility?

Done!

Seeing a ~5x build speedup on CI, although the total check run is quite similar:

Webpack -main (c3a51ae)

Rspack - this PR (22a0385)

Resolved the merge conflict in the release notes file.

Thanks@jasongrout for helping with this PR!

I checked the last commits and they look good. As discussed yesterday during the meeting (jupyterlab/frontends-team-compass#279 (comment)), it would be great to move forward with this so we have the full 4.6 release cycle to put this under more testing and fix potential issues.

Jeremy, I'm taking your comment as a postive review on the parts I've done, and I'm positively reviewing the parts you've done, so I think we've satisfied the review requirement. We also discussed this in the dev meeting yesterday with a positive result. So I think we're good to merge!