Parse error in import.meta.env assignment

Describe the bug

A parse error occurred in the code where import.meta.env is being written to.
Code causing the error:

import.meta.env = import.meta.env || {}
import.meta.env.__config__ = 'true'

Below are the details of the error:

 FAIL  test/basic.test.ts [ test/basic.test.ts ]
Error: Transform failed with 1 error:

[PARSE_ERROR] Error: Cannot assign to this expression
   ╭─[ home/projects/vitest-dev-vitest-wdp1vbyr/src/env.ts:2:3 ]
   │
 2 │   Object.assign(/* istanbul ignore next */ globalThis.__vitest_worker__?.metaEnv ?? import.meta.env) = Object.assign(/* istanbul ignore next */ globalThis.__vitest_worker__?.metaEnv ?? import.meta.env) || {}
   │   ─────────────────────────────────────────────────┬────────────────────────────────────────────────  
   │                                                    ╰────────────────────────────────────────────────── 
───╯

  Plugin: vite:oxc
  File: /home/projects/vitest-dev-vitest-wdp1vbyr/src/env.ts
 ❯ transformWithOxc node_modules/.pnpm/vite@8.0.3_@emnapi+core@1.9.2_@emnapi+runtime@1.9.2/node_modules/vite/dist/node/chunks/node.js:3839:19
 ❯ TransformPluginContext.transform node_modules/.pnpm/vite@8.0.3_@emnapi+core@1.9.2_@emnapi+runtime@1.9.2/node_modules/vite/dist/node/chunks/node.js:3907:26
 ❯ EnvironmentPluginContainer.transform node_modules/.pnpm/vite@8.0.3_@emnapi+core@1.9.2_@emnapi+runtime@1.9.2/node_modules/vite/dist/node/chunks/node.js:30167:51
 ❯ loadAndTransform node_modules/.pnpm/vite@8.0.3_@emnapi+core@1.9.2_@emnapi+runtime@1.9.2/node_modules/vite/dist/node/chunks/node.js:24296:26

Also, thank you for the help in the Q&A

Reproduction

https://stackblitz.com/edit/vitest-dev-vitest-wdp1vbyr?file=test%2Fbasic.test.ts,src%2Fenv.ts

System Info

System:
    OS: Linux 5.0 undefined
    CPU: (8) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
    Memory: 0 Bytes / 0 Bytes
    Shell: 1.0 - /bin/jsh
  Binaries:
    Node: 22.22.0 - /usr/local/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 10.8.2 - /usr/local/bin/npm
    pnpm: 8.15.6 - /usr/local/bin/pnpm
  npmPackages:
    @vitest/coverage-v8: latest => 4.1.2 
    @vitest/ui: latest => 4.1.2 
    vite: latest => 8.0.3 
    vitest: latest => 4.1.2

Used Package Manager

pnpm

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.
• 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.

Start with src/env.ts and reproduce the failure using the linked StackBlitz example or test/basic.test.ts. Check how the import.meta.env assignment is transformed by Vite's OXC plugin. Done means the example no longer produces a parse error and the environment assignment still works.