Styles not being recompiled when using --watch mode

[stigvanbrabant]

Describe the bug

When building my library in watch mode it compiles the css on first build but when rebuilding on change it removes the css file from the folder and only compiles the js files, anybody got an idea why this is happening and how i could resolve this?

Reproduction

https://github.com/stigvanbrabant/vite-issue-repro

System Info

Output of npx envinfo --system --npmPackages vite,@vitejs/plugin-vue --binaries --browsers:

  System:
    OS: Linux 5.8 Ubuntu 20.04.2 LTS (Focal Fossa)
    CPU: (16) x64 AMD Ryzen 7 3700X 8-Core Processor
    Memory: 3.20 GB / 15.64 GB
    Container: Yes
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 14.16.1 - ~/.nvm/versions/node/v14.16.1/bin/node
    npm: 7.10.0 - ~/.nvm/versions/node/v14.16.1/bin/npm
  Browsers:
    Chrome: 90.0.4430.72
    Firefox: 87.0
  npmPackages:
    @vitejs/plugin-vue: ^1.2.1 => 1.2.1 
    vite: ^2.2.1 => 2.2.1 

Used package manager: npm

Logs

❯ npm run build:watch

> my-lib@0.0.0 build:watch
> vite build --watch

vite v2.2.1 building for production...

watching for file changes...

build started...
transforming (1) src/bundle.js
warn - Tailwind is not purging unused styles because no template paths have been provided.
warn - If you have manually configured PurgeCSS outside of Tailwind or are deliberately not removing unused styles, set `purge: false` in your Tailwind config file to silence this warning.
warn - https://tailwindcss.com/docs/controlling-file-size/#removing-unused-css
✓ 4 modules transformed.
dist/style.css       3157.76kb / brotli: skipped (large chunk)
dist/my-lib.es.js   0.24kb / brotli: 0.17kb
dist/my-lib.umd.js   0.46kb / brotli: 0.26kb
built in 9038ms.

build started...
✓ 4 modules transformed.
dist/my-lib.es.js   0.24kb / brotli: 0.17kb
dist/my-lib.umd.js   0.46kb / brotli: 0.26kb
built in 1347ms.

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[Shinigami92]

@stafyniaksacha You build the feature in #1449 🙂
Do you know how we can fix that? Maybe you could provide a PR?

[stafyniaksacha]

@Shinigami92 Yes, I got the issue this morning too, I am going to investigate

[y1d7ng]

fixed by #3887, 2.4.0-beta.0 and later versions work fine.