types: postcss plugin doesn't accept PluginCreator (i.e: tailwindcss)

[zanona]

Describe the bug

Under vite css config we can add postcss plugins, however vite's type definitions state that plugins is an array of PostCSS.Plugin[]

vite/packages/vite/src/node/plugins/css.ts

Lines 70 to 74 in 895a7d6

	postcss?:
	| string
	| (PostCSS.ProcessOptions & {
	plugins?: PostCSS.Plugin[]
	})

The problem with this is that some plugins can return a PostCSS.PluginCreator instead, such as tailwindcss

import { PluginCreator } from 'postcss'
import type { Config } from './config.d'

declare const plugin: PluginCreator<string | Config | { config: string | Config }>

export { Config }
export default plugin

This disparity, makes it difficult to have valid typings when importing a tailwind config which outputs as PluginCreator on vite

PostCSS has their own type for allowing multiple plugin type formats as PostCSS.AcceptedPlugin

export type AcceptedPlugin =
  | Plugin
  | PluginCreator<any>
  | OldPlugin<any>
  | TransformCallback
  | {
      postcss: TransformCallback | Processor
    }
  | Processor

The suggestion here would be to replace PostCSS.Plugin[] with PostCSS.AcceptedPlugin[] as the return type for the plugins property under vite postcss config:

--- packages/vite/src/node/plugins/css.ts
+++ packages/vite/src/node/plugins/css.ts
export interface CSSOptions {
  /**
   * https://github.com/css-modules/postcss-modules
   */
  modules?: CSSModulesOptions | false
  preprocessorOptions?: Record<string, any>
  postcss?:
    | string
    | (PostCSS.ProcessOptions & {
-        plugins?: PostCSS.Plugin[]
+       plugins?: PostCSS.AcceptedPlugin[]
      })
  /**
   * Enables css sourcemaps during dev
   * @default false
   * @experimental
   */
  devSourcemap?: boolean
}

Reproduction

N/A Type definition only

System Info

System:
    OS: Linux 5.18 Arch Linux
    CPU: (12) x64 Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz
    Memory: 8.56 GB / 15.51 GB
    Container: Yes
    Shell: 5.1.16 - /bin/bash
  Binaries:
    Node: 16.13.2 - ~/.nvm/versions/node/v16.13.2/bin/node
    Yarn: 1.22.19 - /usr/bin/yarn
    npm: 8.7.0 - ~/.nvm/versions/node/v16.13.2/bin/npm
  Browsers:
    Chromium: 102.0.5005.115
    Firefox: 101.0.1
  npmPackages:
    vite: ^2.8.6 => 2.9.13

Used Package Manager

npm

Logs

No response

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• The provided reproduction is a minimal reproducible example of the bug.