Closing rpc while "onAfterSuiteRun" was pending when another RPC call fails during teardown #11925

Describe the bug

With coverage enabled, a run where every test passes can sometimes fail with:

⎯⎯⎯⎯ Unhandled Rejection ⎯⎯⎯⎯⎯
EnvironmentTeardownError: [vitest-worker]: Closing rpc while "onAfterSuiteRun" was pending
This error originated in "test/sum.test.js" test file. It doesn't mean the error was thrown inside the file itself, but while it was running.

 Test Files  1 passed (1)
      Tests  1 passed (1)
     Errors  1 error

This seems to be because rpcDone() in packages/vitest/src/runtime/rpc.ts uses Promise.all. When the worker finishes, it waits on rpcDone(), then rejects whatever is still pending. If any in-flight call rejects, Promise.all settles right away, and the cleanup then rejects onAfterSuiteRun. Nothing handles that rejection, because onAfterSuiteRun is sent without being awaited (runtime/runners/index.ts).

Switching rpcDone() from Promise.all to Promise.allSettled should fix it. Ignoring EnvironmentTeardownError on the onAfterSuiteRun call, as console.ts does for onUserConsoleLog, would also work.

Reproduction

https://github.com/TrevorBurnham/vitest-onAfterSuiteRun-repro

Pull that repo down and run npm install && npm test. On my Mac, it fails in almost every run with coverage on, and passes with coverage off.

Here's how it makes the non-deterministic bug reproduce almost all the time:

• starts a caught, unawaited import that a plugin fails after 500 ms
• blocks the main process for 1 s from a reporter once the file finishes, standing in for a busy CI machine
• loads a large generated module, so collecting coverage in the worker takes longer than the 100 ms task-update throttle

The README walks through the order of events.

System Info

System:
  OS: macOS 27.2
  CPU: (15) arm64 Apple M5 Pro
Binaries:
  Node: 24.22.2
  npm: 11.19.1
npmPackages:
  @vitest/coverage-v8: 5.1.0 => 5.1.0
  vitest: 5.1.0 => 5.1.0

Used Package Manager

npm