Use fakeTimers does not mock imports from `node:timers` or `node:timers/promises`

[Nokel81]

Describe the bug

According to #7097 this should work not, but it does not.

Reproduction

https://stackblitz.com/edit/vitest-dev-vitest-1gkfprhf?file=test%2Fbasic.test.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: 22.22.3 - /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/ui: latest => 4.1.10 
    vite: latest => 8.2.0 
    vitest: latest => 4.1.10

Used Package Manager

npm

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.

[atharv-sys32]

Hi @sheremet-va. Opened a fix for this: #10878.

vi.useFakeTimers() did not mock setTimeout imported from node:timers or node:timers/promises. The fake timers patch read the timer modules at module load time, before vitest_required is populated, so the module methods were never patched, and Node snapshots ESM named import bindings at first load.

The PR registers node:timers and node:timers/promises as live module stubs in the module runner and reads the timer modules lazily inside the fake timers install(). Regression tests added in test/unit/test/timers-node.test.ts (named, default, namespace, promises, and require imports), passing in the threads, forks, and vmThreads pools. It also fixes the Windows typechecker OOM test that was already failing on main.

Would appreciate a look.

[hi-ogawa]

Apparently, docs have never mentioned faketimers mocking node:timers and node:timers/promises, so technically it's not settled what's the expected behavior. Also enabling mocking for this may be considered breaking change.