vite.config resolve.extensions.length=0 is error

[jeff-fe]

Describe the bug

import { defineConfig } from 'vite'
import vue from '@vitejs/plugin-vue'

export default defineConfig({
  resolve: {
      extensions: []  // error
    },
  plugins: [vue()]
})

Reproduction

vite 2.4.1

System Info

System:
    OS: macOS 10.15.7
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
    Memory: 502.05 MB / 16.00 GB
    Shell: 5.7.1 - /bin/zsh
  Binaries:
    Node: 14.16.0 - /usr/local/bin/node
    Yarn: 1.22.10 - /usr/local/bin/yarn
    npm: 6.14.11 - /usr/local/bin/npm
  Browsers:
    Firefox: 71.0
    Safari: 14.0.2
  npmPackages:
    @vitejs/plugin-vue: ^1.2.4 => 1.2.4
    vite: 2.3.7 => 2.3.7

Used Package Manager

npm

Logs

No response

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.

[jeff-fe]

hi @antfu ，I have other problem is not solved. Please help

import { defineConfig } from 'vite'
import vue from '@vitejs/plugin-vue'

export default defineConfig({
  resolve: {
      extensions: ['.js']
    },
  plugins: [vue()]
})

This config in vite 2.3.8 is work ok,
but in vite 2.4.0+ is error
@vite/client http request is 404 not found.

Thanks♪(･ω･)ﾉ

[ygj6]

I am fixing this problem, because PR #4061 changed @vite/client to .mjs suffix

vite/packages/vite/src/node/constants.ts

Line 44 in d377aae

export const CLIENT_ENTRY = require.resolve('vite/dist/client/client.mjs')

Adding .mjs works fine

resolve: {
    extensions: ['.js','.mjs']
}

[jeff-fe]

Thanks @ygj6