Update to webpack v5

[jaydenseric]

We should be optimizing our packages for the most recent version of webpack, which is now v5.

Importantly, it understands the package exports field:

• https://nodejs.org/api/packages.html#packages_exports
• https://webpack.js.org/guides/package-exports

Also, it doesn't automatically polyfill the Node.js process global for the browser. Right now, I'm trying to size-limit test a package containing React component code like this:

// Allow the display name to be eliminated from production bundles.
if (typeof process === 'object' && process.env.NODE_ENV !== 'production')
  Foo.displayName = 'Foo';

Webpack v4 sees the process related code, and inserts a massive ./node_modules/process/browser.js shim that can not be ignored by the size-limit config ignore option, because that shim is added by webpack and is not imported anywhere in the code I'm testing.

[ai]

Yeap. I like to migrate to webpack 5, but do not have time to do this, since spending all my time with Logux State.

Can you send PR?

[jaydenseric]

Logux State 👀

Does only the @size-limit/webpack need work? It seems so running npm ls webpack:

├─┬ @size-limit/preset-small-lib@4.7.0
│ └─┬ @size-limit/webpack@4.7.0
│   ├─┬ css-loader@5.0.1
│   │ └── webpack@4.44.2 deduped
│   ├─┬ file-loader@6.2.0
│   │ └── webpack@4.44.2 deduped
│   ├─┬ optimize-css-assets-webpack-plugin@5.0.4
│   │ └── webpack@4.44.2 deduped
│   ├─┬ style-loader@2.0.0
│   │ └── webpack@4.44.2 deduped
│   └── webpack@4.44.2

[ai]

Yeap, only @size-limit/webpack