use sideEffects:fasle in package.json, ignore sass dependencies, generated css is missing in the output dir

[gisshan2012]

Version

15.0.0

Reproduction link

https://github.com/gisboyshan/vue-loader-nocss.git

Steps to reproduce

yarn build

What is expected?

generated css

What is actually happening?

generated css is missing in the output dir

[LinusBorg]

Well, the css is a side effect.

See: https://webpack.js.org/guides/tree-shaking/#mark-the-file-as-side-effect-free

Note that any imported file is subject to tree shaking. This means if you use something like css-loader in your project and import a CSS file, it needs to be added to the side effect list so it will not be unintentionally dropped in production mode:

{
  "name": "your-project",
  "sideEffects": [
    "./src/some-side-effectful-file.js",
    "*.css"
  ]
}