v2.0.0-alpha.4

[markerikson]

This is an alpha release for Redux Toolkit 2.0. This release has many changes to our build setup and published package contents, updates the redux and redux-thunk deps to the latest alphas, updates the immer dep to the latest 10.x beta, and may have breaking changes.

Changelog

ESM/CJS Package Compatibility

The biggest theme of the Redux v5 and RTK 2.0 releases is trying to get "true" ESM package publishing compatibility in place, while still supporting CJS in the published package.

Earlier alphas made changes to the package.json contents and published build artifacts in an attempt to get ESM+CJS compat working correctly, but those alphas had several varying compat issues.

We've set up a battery of example applications in the RTK repo that use a variety of build tools (currently CRA4, CRA5, Next 13, and Vite, Node CJS mode, and Node ESM mode), to verify that Redux and Redux Toolkit compile, import, and run correctly with both TS and various bundlers. We've also set up a check using a custom CLI wrapper around https://arethetypeswrong.github.io to check for potential packaging incompatibilities.

This release changes the names and contents of the published build artifacts, and the various exports/module/main fields in package.json to point to those.

We already tried to point to ESM build artifacts as the default. That should hopefully be be more consistent now.

As of this release, we think we have ESM+CJS compat working correctly, but we ask that the community try out the alphas in your apps and let us know of any compat problems!

Note: The one known potential issue is that TypeScript's new moduleResolution: "node16" mode may see a mismatch between the ESM artifacts and the TS typedefs when imported in a Node CJS environment, and [that may allow hypothetically-incorrect import usage. (See ongoing discussion in https://github.com/arethetypeswrong/arethetypeswrong.github.io/issues/21 .) In practice, we think that probably won't be a concern, and we'll do further investigation before a final release.

Dropping UMD Builds

Redux has always shipped with UMD build artifacts. These are primarily meant for direct import as script tags, such as in a CodePen or a no-bundler build environment.

For now, we're dropping those build artifacts from the published package, on the grounds that the use cases seem pretty rare today.

We do have browser-ready ESM build artifacts included, which already have process.env.NODE_ENV compiled away for either development or production behavior. These can be loaded via a script tag that points to that file on Unpkg.

If you have strong use cases for us continuing to include UMD build artifacts, please let us know!

Immer 10 Beta

Immer 10 is now in beta. It has several major changes, including faster perf, dropping ES5 environment support, and switching from a default export to only named exports.

We've updated RTK to depend on [email protected].

Performance testing in an artificial RTKQ stress test project showed significant perf increases when dealing with many RTKQ-connected components loading, and that was directly due to Immer-powered reducers executing much faster.

While reducers are not usually the bottleneck in React+Redux apps, this looks like it will be a very nice improvement!

What's Changed

• Fix lint problems and enable linting on CI by @thorn0 in Fix lint problems and enable linting on CI #2992
• Allow TS isolatedModules flag to be set for safer transpilation by @matmannion in Allow TS isolatedModules flag to be set for safer transpilation #2911
• Test published artifacts in CI by @markerikson in Test published artifacts in CI #3213
• Use Git revision in version and add Node CI examples by @markerikson in Use Git revision in version and add Node CI examples #3258
• Add arethetypeswrong automated CLI check by @markerikson in Add arethetypeswrong automated CLI check #3294
• remove "alternative" from descriptions of builder callback by @EskiMojo14 in remove "alternative" from descriptions of builder callback #3296
• update tip regarding overrideExisting to match actual behaviour by @EskiMojo14 in update tip regarding overrideExisting to match actual behaviour #3305
• Add attw CLI option to treat problems as non-errors by @markerikson in Add attw CLI option to treat problems as non-errors #3316
• Rework build setup and hopefully fix ESM compat issues by @markerikson in Rework build setup and hopefully fix ESM compat issues #3318
• Bump Immer to 10.0-beta by @markerikson in Bump Immer to 10.0-beta #3320

Full Changelog: v2.0.0-alpha.2...v2.0.0-alpha.4

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This discussion was created from the release v2.0.0-alpha.4.

[einarq]

immerjs/immer#1015 (comment)

[einarq]

Also get this TS issue:

[einarq]

Also got this problem when building the code (using Webpack 5):

169.7 ERROR in ./node_modules/@reduxjs/toolkit/dist/redux-toolkit.modern.mjs 541:15-22
169.7 Module not found: Error: Can't resolve 'process/browser' in '/usr/src/app/node_modules/@reduxjs/toolkit/dist'
169.7 Did you mean 'browser.js'?
169.7 BREAKING CHANGE: The request 'process/browser' failed to resolve only because it was resolved as fully specified
169.7 (probably because the origin is strict EcmaScript Module, e. g. a module with javascript mimetype, a '*.mjs' file, or a '*.js' file where the package.json contains '"type": "module"').

Which was resolved by this workaround:
react-dnd/react-dnd#3425 (comment)
resolve: { fallback: { 'process/browser': require.resolve('process/browser'), } }

[einarq]

@markerikson
This actually fails inside RTKQ as well, when cache is removed automatically after a little while (for me it seems to happen when the window loses focus).

I created a small repro and commented on the Immer 10 thread:
immerjs/immer#1015 (comment)