Minifying the code in 3 passes leads to a syntax error

Describe the bug

If set up terser with passes >=3

terserOptions: {
  compress: {
    passes: 3
  }
}

The application does not load, you may see an error in the console:

Uncaught SyntaxError: identifier starts immediately after numeric literal

The cause of the problem is the minification of the code using a terser. It occurs if 3 or more passes are configured.

I thought this was a problem with the terser and tried for a long time to reproduce the error in REPL. But no matter what I do, everything works as expected and it happens only when the code is optimized through the Vite.

Reproduction

Reproduction repo: cawa-93/vite-terser-issue

1. Clone reproduction repo: git clone [e-mail]:cawa-93/vite-terser-issue.git
2. cd ./vite-terser-issue
3. Install deps: npm ci
4. Build and serve npm run build && npm run sevce
5. Open app http://localhost:5000

System Info

  System:
    OS: Windows 10 10.0.19042
    CPU: (16) x64 AMD Ryzen 7 4800H with Radeon Graphics
    Memory: 9.36 GB / 15.42 GB
  Binaries:
    Node: 14.16.1 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.22.10 - ~\AppData\Roaming\npm\yarn.CMD
    npm: 7.9.0 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Edge: Spartan (44.19041.423.0), Chromium (90.0.818.41)
    Internet Explorer: 11.0.19041.1
  npmPackages:
    @vitejs/plugin-vue: ^1.2.1 => 1.2.1
    vite: ^2.2.0 => 2.2.0

Used package manager: npm

Before submitting the issue, please make sure you do the following

• 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.
• Provide a description in this issue that describes the bug.
• 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.

[sodatea]

It’s because terser moves the preloadMarker around in the 3rd pass. The marker need to be processed by the buildImportAnalysisPlugin later. Change of its position thus results in corrupted code.

[ygj6]

thx, I will do it right now.