False positive error message

[unional]

Describe the bug

"build.lib.formats" will be ignored because "build.rollupOptions.output" is already an array format

I need to use build.rollupOptions.output, e.g.:

{
  build: {
    rollupOptions: {
      output: [
        { dir: 'cjs', format: 'cjs', sourcemap: true },
        { dir: 'esm', format: 'es', sourcemap: true }
      ]
    }
  }
} 

When I skip build.lib.formats, it will fail with:

Option "build.lib.name" is required when output formats include "umd" or "iife".

but it is not building umd or iife, thus build.lib.name is not needed.

Currently, I have to either declare a phantom build.lib.name, or build.lib.formats: [] which will emit this warning.

Reproduction

https://stackblitz.com/edit/vitejs-vite-3dmwtq?file=vite.config.js

Steps to reproduce

build

System Info

System:
    OS: macOS 12.6.1
    CPU: (10) arm64 Apple M1 Pro
    Memory: 95.92 MB / 16.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 16.14.2 - ~/.nvm/versions/node/v16.14.2/bin/node
    npm: 8.5.0 - ~/.nvm/versions/node/v16.14.2/bin/npm
  Browsers:
    Brave Browser: 107.1.45.123
    Chrome: 107.0.5304.110
    Firefox: 105.0.3
    Safari: 16.1

Used Package Manager

pnpm

Logs

Click to expend!

```sh > vite build "--" "--debug"

vite:config bundled config file loaded in 525.33ms +0ms
vite:esbuild init tsconfck (root: /Users/hwong/pan/pats) +0ms
vite:esbuild init tsconfck (root: /Users/hwong/pan/pats) +66ms
vite:esbuild init tsconfck (root: /Users/hwong/pan/pats) +0ms
vite:esbuild init tsconfck (root: /Users/hwong/pan/pats) +0ms
vite:esbuild init tsconfck end +249ms
vite:esbuild init tsconfck end +0ms
vite:esbuild init tsconfck end +0ms
vite:esbuild init tsconfck end +0ms
vite:config using resolved config: {
vite:config plugins: [
vite:config 'vite:build-metadata',
vite:config 'vite:pre-alias',
vite:config 'alias',
vite:config 'vite:react-babel',
vite:config 'vite:react-refresh',
vite:config 'vite:react-jsx',
vite:config 'node-externals',
vite:config 'vite-plugin-windicss:alias',
vite:config 'vite-plugin-windicss:groups',
vite:config 'vite:modulepreload-polyfill',
vite:config 'vite:resolve',
vite:config 'vite:html-inline-proxy',
vite:config 'vite:css',
vite:config 'vite:esbuild',
vite:config 'vite:json',
vite:config 'vite:wasm-helper',
vite:config 'vite:worker',
vite:config 'vite:asset',
vite:config 'vite-plugin-windicss',
vite:config 'vite-plugin-windicss:css',
vite:config 'vite-plugin-windicss:css:svelte',
vite:config 'vite-plugin-windicss:devtools',
vite:config 'vite:wasm-fallback',
vite:config 'vite:define',
vite:config 'vite:css-post',
vite:config 'vite:build-html',
vite:config 'vite:worker-import-meta-url',
vite:config 'vite:force-systemjs-wrap-complete',
vite:config 'vite:watch-package-data',
vite:config 'commonjs',
vite:config 'vite:data-uri',
vite:config 'vite:asset-import-meta-url',
vite:config 'typescript',
vite:config 'vite:dynamic-import-vars',
vite:config 'vite:import-glob',
vite:config 'vite-plugin-windicss:entry',
vite:config 'vite:build-import-analysis',
vite:config 'vite:esbuild-transpile',
vite:config 'vite:terser',
vite:config 'vite:reporter',
vite:config 'vite:load-fallback'
vite:config ],
vite:config build: {
vite:config target: [ 'es2020', 'edge88', 'firefox78', 'chrome87', 'safari13' ],
vite:config polyfillModulePreload: true,
vite:config outDir: 'dist',
vite:config assetsDir: 'assets',
vite:config assetsInlineLimit: 4096,
vite:config cssCodeSplit: false,
vite:config cssTarget: [ 'es2020', 'edge88', 'firefox78', 'chrome87', 'safari13' ],
vite:config sourcemap: true,
vite:config rollupOptions: { plugins: [Array], output: [Array] },
vite:config minify: 'esbuild',
vite:config terserOptions: {},
vite:config write: true,
vite:config emptyOutDir: null,
vite:config manifest: false,
vite:config lib: {
vite:config entry: '/Users/hwong/pan/pats/components/react-ui/ts/index.ts',
vite:config fileName: 'pats-react-ui',
vite:config formats: []
vite:config },
vite:config ssr: false,
vite:config ssrManifest: false,
vite:config reportCompressedSize: true,
vite:config chunkSizeWarningLimit: 500,
vite:config watch: null,
vite:config commonjsOptions: { include: [Array], extensions: [Array] },
vite:config dynamicImportVarsOptions: { warnOnError: true, exclude: [Array] }
vite:config },
vite:config test: {
vite:config environment: 'jsdom',
vite:config setupFiles: 'scripts/test-setup.ts',
vite:config threads: false
vite:config },
vite:config resolve: {
vite:config alias: [ [Object], [Object], [Object] ],
vite:config dedupe: [ 'react', 'react-dom' ]
vite:config },
vite:config optimizeDeps: {
vite:config disabled: 'build',
vite:config force: undefined,
vite:config include: [ 'react/jsx-runtime', 'react/jsx-dev-runtime', 'react' ],
vite:config esbuildOptions: { preserveSymlinks: undefined }
vite:config },
vite:config configFile: '/Users/hwong/pan/pats/components/react-ui/vite.config.ts',
vite:config configFileDependencies: [ '/Users/hwong/pan/pats/components/react-ui/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 optimizeDeps: { force: undefined },
vite:config build: {}
vite:config },
vite:config root: '/Users/hwong/pan/pats/components/react-ui',
vite:config base: '/',
vite:config publicDir: '/Users/hwong/pan/pats/components/react-ui/public',
vite:config cacheDir: '/Users/hwong/pan/pats/components/react-ui/node_modules/.vite',
vite:config command: 'build',
vite:config mode: 'production',
vite:config ssr: {
vite:config format: 'esm',
vite:config target: 'node',
vite:config optimizeDeps: { disabled: true, esbuildOptions: [Object] }
vite:config },
vite:config isWorker: false,
vite:config mainConfig: null,
vite:config isProduction: true,
vite:config server: {
vite:config preTransformRequests: true,
vite:config middlewareMode: false,
vite:config fs: { strict: true, allow: [Array], deny: [Array] }
vite:config },
vite:config preview: {
vite:config port: undefined,
vite:config strictPort: undefined,
vite:config host: undefined,
vite:config https: undefined,
vite:config open: undefined,
vite:config proxy: undefined,
vite:config cors: undefined,
vite:config headers: undefined
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 hasErrorLogged: [Function: hasErrorLogged]
vite:config },
vite:config packageCache: Map(0) { set: [Function (anonymous)] },
vite:config createResolver: [Function: createResolver],
vite:config worker: {
vite:config format: 'iife',
vite:config plugins: [
vite:config 'vite:build-metadata',
vite:config 'vite:pre-alias',
vite:config 'alias',
vite:config 'vite:modulepreload-polyfill',
vite:config 'vite:resolve',
vite:config 'vite:html-inline-proxy',
vite:config 'vite:css',
vite:config 'vite:esbuild',
vite:config 'vite:json',
vite:config 'vite:wasm-helper',
vite:config 'vite:worker',
vite:config 'vite:asset',
vite:config 'vite:wasm-fallback',
vite:config 'vite:define',
vite:config 'vite:css-post',
vite:config 'vite:build-html',
vite:config 'vite:worker-import-meta-url',
vite:config 'vite:force-systemjs-wrap-complete',
vite:config 'vite:watch-package-data',
vite:config 'commonjs',
vite:config 'vite:data-uri',
vite:config 'vite:asset-import-meta-url',
vite:config 'typescript',
vite:config 'vite:dynamic-import-vars',
vite:config 'vite:import-glob',
vite:config 'vite:build-import-analysis',
vite:config 'vite:esbuild-transpile',
vite:config 'vite:terser',
vite:config 'vite:reporter',
vite:config 'vite:load-fallback'
vite:config ],
vite:config rollupOptions: {},
vite:config getSortedPlugins: [Function: getSortedPlugins],
vite:config getSortedPluginHooks: [Function: getSortedPluginHooks]
vite:config },
vite:config appType: 'spa',
vite:config experimental: { importGlobRestoreExtension: false, hmrPartialAccept: false },
vite:config getSortedPlugins: [Function: getSortedPlugins],
vite:config getSortedPluginHooks: [Function: getSortedPluginHooks]
vite:config } +320ms
vite v3.1.8 building for production...
"build.lib.formats" will be ignored because "build.rollupOptions.output" is already an array format
✓ 52 modules transformed.
cjs/pats-react-ui.cjs 14.46 KiB / gzip: 4.70 KiB
cjs/pats-react-ui.cjs.map 57.96 KiB
esm/pats-react-ui.js 19.42 KiB / gzip: 5.23 KiB
esm/pats-react-ui.js.map 61.64 KiB

</details>

### Validations

- [X] Follow our [Code of Conduct](https://github.com/vitejs/vite/blob/main/CODE_OF_CONDUCT.md)
- [X] Read the [Contributing Guidelines](https://github.com/vitejs/vite/blob/main/CONTRIBUTING.md).
- [X] Read the [docs](https://vitejs.dev/guide).
- [X] Check that there isn't [already an issue](https://github.com/vitejs/vite/issues) that reports the same bug to avoid creating a duplicate.
- [X] 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 [vuejs/core](https://github.com/vuejs/core) instead.
- [X] Check that this is a concrete bug. For Q&A open a [GitHub Discussion](https://github.com/vitejs/vite/discussions) or join our [Discord Chat Server](https://chat.vitejs.dev/).
- [X] The provided reproduction is a [minimal reproducible example](https://stackoverflow.com/help/minimal-reproducible-example) of the bug.

[sapphi-red]

This is fixed by #9886 and will be released in 4.0.0.