@vite/plugin-legacy bug with buildPolyfillChunk and const type variable

[Nepo92]

Describe the bug

I try build my project with vite 3.

I use @vitejs/plugin-legacy for support old browsers.

my vite.config.js file is

import { resolve } from 'path';
import { defineConfig } from 'vite';
import vue from '@vitejs/plugin-vue';
import legacy from '@vitejs/plugin-legacy';

export default defineConfig({
  base: '/',
  build: {
    rollupOptions: {
      input: {
        main: resolve(__dirname, 'pages/index.html'),
        about: resolve(__dirname, 'pages/about/index.html'),
      },
    },
  },
  server: {
    port: 3000,
    host: '0.0.0.0',
    hrm: true,
  },
  plugins: [
    vue(),
    legacy({
      targets: ['defaults', 'not IE 11'],
    }),
  ],
});

I run script yarn build but i have a problem

System Info

error during build:
Error: Transform failed with 1 error:
assets/polyfills-legacy.a7649e24.js:2104:3312: ERROR: Transforming const to the configured target environment ("es5" + 2 overrides) is not supported yet
    at failureErrorWithLog (/Users/aleksandreremeev/1bit/bitrix-vite-template/node_modules/esbuild/lib/main.js:1624:15)
    at /Users/aleksandreremeev/1bit/bitrix-vite-template/node_modules/esbuild/lib/main.js:1413:29
    at /Users/aleksandreremeev/1bit/bitrix-vite-template/node_modules/esbuild/lib/main.js:678:9
    at handleIncomingPacket (/Users/aleksandreremeev/1bit/bitrix-vite-template/node_modules/esbuild/lib/main.js:775:9)
    at Socket.readFromStdout (/Users/aleksandreremeev/1bit/bitrix-vite-template/node_modules/esbuild/lib/main.js:644:7)
    at Socket.emit (events.js:400:28)
    at addChunk (internal/streams/readable.js:293:12)
    at readableAddChunk (internal/streams/readable.js:267:9)
    at Socket.Readable.push (internal/streams/readable.js:206:10)
    at Pipe.onStreamRead (internal/stream_base_commons.js:188:23)

Used Package Manager

yarn

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 vuejs/core 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.

[github-actions]

Hello @Nepo92. Please provide a minimal reproduction using a GitHub repository or StackBlitz. Issues marked with need reproduction will be closed if they have no activity within 3 days.

[inori1707]

I also encountered this problem, my project failed to build since yesterday. After looking into it I find that maybe cause by systemjs's 6.12.2 release. It include a "const" statement in "dist/s.min.js" which imported by @vite/plugin-legacy.

So we may need wait for its fix or use "resolution" or "overrides" field of package manager as a temporary workaround.
Maybe @vite/plugin-legacy should pin his dependencies version?

[shoyuf]

I also encountered this problem, my project failed to build since yesterday. After looking into it I find that maybe cause by systemjs's 6.12.2 release. It include a "const" statement in "dist/s.min.js" which imported by @vite/plugin-legacy.

So we may need wait for its fix or use "resolution" or "overrides" field of package manager as a temporary workaround. Maybe @vite/plugin-legacy should pin his dependencies version?

i use systemjs@6.12.1, it's has same problem Actually, it's systemjs@6.12.2

[imindzzz]

use yarn create vite my-app --template react to create a new empty project that can reproduce the problem
just by default option

// vite.config.js
import legacy from '@vitejs/plugin-legacy'

export default {
  plugins: [
    legacy({
      targets: ['defaults', 'not IE 11']
    })
  ]
}

[shoyuf]

I also encountered this problem, my project failed to build since yesterday. After looking into it I find that maybe cause by systemjs's 6.12.2 release. It include a "const" statement in "dist/s.min.js" which imported by @vite/plugin-legacy.
So we may need wait for its fix or use "resolution" or "overrides" field of package manager as a temporary workaround. Maybe @vite/plugin-legacy should pin his dependencies version?

i use systemjs@6.12.1, it's has same problem

I set externalSystemJS to true resolved this problem

[haoqunjiang]

Can be reproduced by pnpm create vue@2 vite-issue-9618 --default

[inori1707]

@patak-dev @bluwy Thanks for quick fix! But can you check if this fix will break the compatibility of es2015 unsupported browser. Since it skip the transform of polyfills chunk, it will left es2015 syntax to output