Could not resolve error on .js extension in import with TypeScript

[ai]

Describe the bug

Short

If a TypeScript file has index.js in import, Vite will not find a file.

Long

1. In native ESM we must have full path to file including index.js. Just import '../dir/' will not work.
2. In Node.js TS projects it is recommended to have .js extension import '../dir/index.js' even if source have .ts extension because TS is compiler and technically, it will be .js in the end (if I understand TS correctly).
3. But import '../dir/' → import '../dir/index.js' migrate broke Vite with an error:

Could not resolve '../dir/index.js' from index.ts

Changing import '../dir/index.js'' → import '../dir/ (or to import '../dir/index) will break native ESM in universal Node/browser packages inside my monorepo.

Reproduction

Reproduction

git clone git@github.com:ai/vite-ts-indexjs-bug.git && cd vite-ts-indexjs-bug
yarn
npx vite build

System Info

System:
    OS: Linux 5.14 Fedora 34 (Workstation Edition) 34 (Workstation Edition)
    CPU: (8) x64 11th Gen Intel(R) Core(TM) i7-1185G7 @ 3.00GHz
    Memory: 2.24 GB / 15.33 GB
    Container: Yes
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 17.0.1 - ~/.asdf/installs/nodejs/17.0.1/bin/node
    Yarn: 1.22.15 - ~/.asdf/shims/yarn
    npm: 8.1.0 - ~/.asdf/plugins/nodejs/shims/npm
  Browsers:
    Chrome: 95.0.4638.69
    Firefox: 94.0

Used Package Manager

yarn

Logs

vite:config bundled config file loaded in 16.49ms +0ms
  vite:config using resolved config: {
  vite:config   plugins: [
  vite:config     'alias',
  vite:config     'vite:modulepreload-polyfill',
  vite:config     'vite:resolve',
  vite:config     'vite:html-inline-script-proxy',
  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:asset-import-meta-url',
  vite:config     'vite:build-import-analysis',
  vite:config     'vite:esbuild-transpile',
  vite:config     'vite:reporter',
  vite:config     'vite:load-fallback'
  vite:config   ],
  vite:config   build: {
  vite:config     target: [ 'es2019', 'edge88', 'firefox78', 'chrome87', 'safari13.1' ],
  vite:config     polyfillModulePreload: true,
  vite:config     outDir: 'dist',
  vite:config     assetsDir: 'assets',
  vite:config     assetsInlineLimit: 4096,
  vite:config     cssCodeSplit: true,
  vite:config     cssTarget: [ 'es2019', 'edge88', 'firefox78', 'chrome87', 'safari13.1' ],
  vite:config     sourcemap: false,
  vite:config     rollupOptions: {},
  vite:config     minify: 'esbuild',
  vite:config     terserOptions: {},
  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     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   configFile: '/home/ai/test/vite.config.js',
  vite:config   configFileDependencies: [ 'vite.config.js' ],
  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: '/home/ai/test',
  vite:config   base: '/',
  vite:config   resolve: { dedupe: undefined, alias: [ [Object], [Object] ] },
  vite:config   publicDir: '/home/ai/test/public',
  vite:config   cacheDir: '/home/ai/test/node_modules/.vite',
  vite:config   command: 'build',
  vite:config   mode: 'production',
  vite:config   isProduction: true,
  vite:config   server: { fs: { strict: undefined, allow: [Array] } },
  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   createResolver: [Function: createResolver],
  vite:config   optimizeDeps: {
  vite:config     esbuildOptions: { keepNames: undefined, preserveSymlinks: undefined }
  vite:config   }
  vite:config } +4ms
vite v2.6.13 building for production...
✓ 3 modules transformed.
Could not resolve './lib.js' from index.ts
error during build:
Error: Could not resolve './lib.js' from index.ts
    at error (/home/ai/test/node_modules/rollup/dist/shared/rollup.js:158:30)
    at ModuleLoader.handleResolveId (/home/ai/test/node_modules/rollup/dist/shared/rollup.js:22306:24)
    at /home/ai/test/node_modules/rollup/dist/shared/rollup.js:22300:26
    at processTicksAndRejections (node:internal/process/task_queues:96:5)

Validations

• Follow our Code of Conduct
• 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.
• 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.
• The provided reproduction is a minimal reproducible example of the bug.

[Niputi]

looks like a duplicate of #3040

[ai]

@rollup/plugin-node-resolve from that issue helped.

Thanks for the search. I tried to find, but was not luck.

[ai]

Should we improve Vite’s TS docs with the solution for this case?

[Niputi]

should not be necessary as the issue got fixed with #5510 which will be in the next 2.7 beta

[ai]

Great to see!

[ai]

Thanks for the very fast response and taking care of tiny DX problems ❤

[Niputi]

your welcome. thanks for making a good issue description, reproduction etc.