Describe the bug

Vite injects css assets in wrong order with dynamic import and css modules.

Reproduction

For example:

You have component Button with default styles (text color: red)


/* button.tsx */
import React from "react"
import classnames from 'classnames'

import styles from './button.module.css'

type ButtonProps = { children: string className?: string onClick?: () => void }

function Button({ children, className, onClick }: ButtonProps) { return <button className={classnames(styles.button, className)} onClick={onClick}>{children} }

export default Button

```css
/* button.module.css */
.button {
    color: red
}

You have Page component. This page use Button component and overrides it styles by passing custom class name as a prop (text color: green)
```
/* home.tsx /*
import React from "react"
```

import Button from "../../components/button/button"

import styles from './home.module.css'

function HomePage() { return

Home page

    <Button className={styles.greenTextButton}>should be green</Button>
</div>

}

export default HomePage

```cs
/* home.module.css */
.greenTextButton {
    color: green;
}

You import Page component with dynamic import.

import React, { lazy, Suspense, useState } from 'react'

const HomePage = lazy(() => import('./pages/home/home'))
const AboutPage = lazy(() => import('./pages/about/about'))

function App() {
  const [page, setPage] = useState('home')
  return (
    <div>
      <a href="#" onClick={() => setPage('home')} style={{ marginRight: '5px' }}>home page</a>
      <a href="#" onClick={() => setPage('about')}>about page</a>

      <Suspense fallback={<div>loading</div>}>
        {page === 'home' && (
          <HomePage />
        )}
        {page === 'about' && (
          <AboutPage />
        )}
      </Suspense>
    </div>
  )
}

export default App

You exepect page styles will override button styles, but they are not (as vite injects styles in wrong order)

P.S. You can reproduce this but with cssCodeSplit: true or false.

System Info

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

  System:
    OS: macOS 11.4
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
    Memory: 94.85 MB / 16.00 GB
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 14.16.1 - ~/.volta/tools/image/node/14.16.1/bin/node
    npm: 6.14.12 - ~/.volta/tools/image/node/14.16.1/bin/npm
  Browsers:
    Chrome: 91.0.4472.114
    Firefox: 89.0
    Safari: 14.1.1
  npmPackages:
    vite: ^2.3.8 => 2.3.8

Used package manager:

Logs

 vite:config bundled config file loaded in 42ms +0ms
  vite:config using resolved config: {
  vite:config   plugins: [
  vite:config     'alias',
  vite:config     'react-refresh',
  vite:config     'vite:dynamic-import-polyfill',
  vite:config     'vite:resolve',
  vite:config     'vite:html',
  vite:config     'vite:css',
  vite:config     'vite:esbuild',
  vite:config     'vite:json',
  vite:config     'vite:wasm',
  vite:config     'vite:worker',
  vite:config     'vite:asset',
  vite:config     'vite:define',
  vite:config     'vite:css-post',
  vite:config     'vite:build-html',
  vite:config     'commonjs',
  vite:config     'vite:data-uri',
  vite:config     'rollup-plugin-dynamic-import-variables',
  vite:config     'vite:import-analysis',
  vite:config     'vite:esbuild-transpile',
  vite:config     'vite:terser',
  vite:config     'vite:reporter'
  vite:config   ],
  vite:config   build: {
  vite:config     target: [ 'es2019', 'edge88', 'firefox78', 'chrome87', 'safari13.1' ],
  vite:config     polyfillDynamicImport: false,
  vite:config     outDir: 'dist',
  vite:config     assetsDir: 'assets',
  vite:config     assetsInlineLimit: 4096,
  vite:config     cssCodeSplit: true,
  vite:config     sourcemap: false,
  vite:config     rollupOptions: {},
  vite:config     commonjsOptions: { include: [Array], extensions: [Array] },
  vite:config     minify: 'terser',
  vite:config     terserOptions: {},
  vite:config     cleanCssOptions: {},
  vite:config     write: true,
  vite:config     emptyOutDir: null,
  vite:config     manifest: false,
  vite:config     lib: false,
  vite:config     ssr: false,
  vite:config     ssrManifest: false,
  vite:config     brotliSize: true,
  vite:config     chunkSizeWarningLimit: 500,
  vite:config     watch: null
  vite:config   },
  vite:config   configFile: '/Users/anatoliidomaratskyi/Work/Mimy/css-code-split-order/vite.config.ts',
  vite:config   configFileDependencies: [ 'vite.config.ts' ],
  vite:config   inlineConfig: {
  vite:config     root: undefined,
  vite:config     base: undefined,
  vite:config     mode: undefined,
  vite:config     configFile: undefined,
  vite:config     logLevel: undefined,
  vite:config     clearScreen: undefined,
  vite:config     build: {}
  vite:config   },
  vite:config   root: '/Users/anatoliidomaratskyi/Work/Mimy/css-code-split-order',
  vite:config   base: '/',
  vite:config   resolve: { dedupe: undefined, alias: [ [Object] ] },
  vite:config   publicDir: '/Users/anatoliidomaratskyi/Work/Mimy/css-code-split-order/public',
  vite:config   cacheDir: '/Users/anatoliidomaratskyi/Work/Mimy/css-code-split-order/node_modules/.vite',
  vite:config   command: 'build',
  vite:config   mode: 'production',
  vite:config   isProduction: true,
  vite:config   server: {
  vite:config     fsServe: {
  vite:config       root: '/Users/anatoliidomaratskyi/Work/Mimy/css-code-split-order',
  vite:config       strict: false
  vite:config     }
  vite:config   },
  vite:config   env: { BASE_URL: '/', MODE: 'production', DEV: false, PROD: true },
  vite:config   assetsInclude: [Function: assetsInclude],
  vite:config   logger: {
  vite:config     hasWarned: false,
  vite:config     info: [Function: info],
  vite:config     warn: [Function: warn],
  vite:config     warnOnce: [Function: warnOnce],
  vite:config     error: [Function: error],
  vite:config     clearScreen: [Function: clearScreen]
  vite:config   },
  vite:config   createResolver: [Function: createResolver],
  vite:config   optimizeDeps: { esbuildOptions: { keepNames: undefined } }
  vite:config } +6ms
vite v2.3.8 building for production...
✓ 33 modules transformed.
dist/assets/favicon.17e50649.svg   1.49kb
dist/index.html                    0.45kb
dist/assets/home.5d3a6e0a.js       0.26kb / brotli: 0.15kb
dist/assets/button.14aa6fb9.js     0.80kb / brotli: 0.41kb
dist/assets/home.deac2baa.css      0.04kb / brotli: 0.04kb
dist/assets/about.563410d2.js      0.60kb / brotli: 0.28kb
dist/assets/button.a44dba50.css    0.03kb / brotli: 0.03kb
dist/assets/index.3938cd91.js      1.55kb / brotli: 0.60kb
dist/assets/about.d57e38e3.css     0.06kb / brotli: 0.05kb
dist/assets/vendor.cc984a25.js     127.61kb / brotli: 36.05kb

Before submitting the issue, please make sure you do the following

[ +] Read the Contributing Guidelines.
[ +] Read the docs.
[ +] Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
[ +] Provide a description in this issue that describes the bug.
[+] Make sure this is a Vite issue and not a framework-specific issue. For example, if it's a Vue SFC related bug, it should likely be reported to https://github.com/vuejs/vue-next instead.
[ +] Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.

vitejs / vite

Vite injects css assets in wrong order with dynamic import and css modules. #3924