Define array constants in the define configuration will be double length in browser

[thiled]

Describe the bug

see Reproduction below

Reproduction

// vite.config.js

export default defineConfig({
  define: {
      a:[1]
    },
});

// browser console

a 

// output

[1,1]

System Info

System:
    OS: Linux 5.13 Arch Linux
    CPU: (4) x64 Intel(R) Core(TM) i5-7200U CPU @ 2.50GHz
    Memory: 2.07 GB / 15.53 GB
    Container: Yes
    Shell: 5.1.8 - /bin/bash
  Binaries:
    Node: 14.15.4 - ~/.nvm/versions/node/v14.15.4/bin/node
    npm: 6.14.10 - ~/.nvm/versions/node/v14.15.4/bin/npm
  Browsers:
    Chromium: 93.0.4577.63
  npmPackages:
    vite: 2.5.10 => 2.5.10

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

[thiled]

this issue should not be closed, the problem still remains in 2.6.4

[bluwy]

I can't reproduce this, would be helpful if you can share the logs where VIte shows the resolved config, and the vite plugins used.

[thiled]

sorry for the part of defineConfig.

Reproduction

import path from 'path';
import { defineConfig } from 'vite';
import { createVuePlugin } from 'vite-plugin-vue2';
import { viteExternalsPlugin } from 'vite-plugin-externals';

export default defineConfig({
  resolve: {
    alias: {
      '@': path.resolve(__dirname, 'src'),
    },
  },
  define: {
    a: [1],
  },
  base: '/',
  plugins: [
    createVuePlugin(),
    viteExternalsPlugin({
      axios: 'axios', // this caused the problem?
    }),
  ],
});

// browser console

a 

// output

[1,1]

[haoqunjiang]

Bug in vite-plugin-externals. Not in Vite core.