Roadmap for version 4

It’s time for a major version bump. This will be a relatively small release but will include a number of necessary breaking changes.

Planned Features

Dependency Updates

• webpack-chain v5 (#3913) CHANGELOG
• css-loader v2 (#3866) CHANGELOG
• copy-webpack-plugin v5 CHANGELOG (a very subtle change, unless you’ve touched its options in config there won’t be any affect)
• Nightwatch v1 (#3388) MIGRATION GUIDE
• Use ESLint v5 by default (#3775) (projects scaffolded with Vue CLI 3.1+ are already using it, for those scaffolded by 3.0.x, here’s the migration guide for eslint and release note of eslint-plugin-vue v5)
• Jest v24 (#3870) RELEASE NOTE
• workbox v4 (#3915) RELEASE NOTE and MIGRATION GUIDE
• core-js 3 (#3912) (It’s an internal change of @vue/babel-preset/app, for now we use core-js 2 by default, babel 7.4.0 supports core-js 3, once we upgraded core-js, some undocumented public APIs may change)

Changed Behavior

• vue-template-loader: preserveWhitespace: false -> whitespace: 'condense' #3853
• use NODE_ENV=production by default if not specified when running vue-cli-service build #3859
• plugin-pwa: manifest.json should be generated during the build process rather than scaffolding #2981

New Features

Most proposed new features other than plugin APIs can also be landed in v3.x so they are not listed here.

• Plugin API: Allow plugins to provide a minimum vue-cli version #3861
• vue upgrade overhaul, allowing running codemods from plugins
• Plugin ordering #1754, #1938

Removed

• Drop Node.js v9 support (in documentation, no need to touch the code)
• remove support for vue-cli-service e2e command (already deprecated since 3.0 rc) (#3774)

Needs Discussion

• <del>Drop unit mocha in favor of Jest only
  • Mostly because mocha-webpack is unmaintained and unlikely to work with webpack 5
  • Need good migration strategy for existing users</del>
• Use mochapack instead of mocha-webpack
• Upgrade to mocha v6

How Can I Help?

Please let us know your thoughts and if we missed anything. We’ll be more than happy to explain our rationale around these decisions if there’s any further questions.

If there’s anything you (and the community) feel strongly about but is not found on this list, please make an effort to send a PR! We’ll be more than happy to accept contributions.

[edimitchel]

Mocha is much faster than Jest. Keep it.

[larixer]

@LinusBorg Great! Yes, I plan to keep on working on mochapack and add Wepback 5 support to it. I will notify you here, when Webpack 5 support will be ready in mochapack.