Discrepancy between `fs.rmSync` and `fs/promises.rm` behavior with `.` and `..` in paths

Why this is a good first issue

Inconsistent behavior between sync and async file deletion methods with specific path patterns.

AI Summary

The issue highlights a discrepancy between `fs.rmSync` and `fs/promises.rm` when handling paths containing `.` and `..`. The sync method succeeds in some cases where the async method fails, indicating inconsistent path resolution logic. The fix likely involves aligning the behavior in the `rimraf` implementation, but requires careful testing to ensure no regressions.

Issue Description

Version

v25.6.1

Platform

Darwin moxy.lan 25.3.0 Darwin Kernel Version 25.3.0: Wed Jan 28 20:47:03 PST 2026; root:xnu-12377.81.4~5/RELEASE_ARM64_T6031 arm64

Subsystem

lib/internal/fs/rimraf.js

What steps will reproduce the bug?

Create a nested folder:

mkdir -p a/b/c/d

Attempt to delete with this weirdly constructed path:

Welcome to Node.js v25.6.1.
Type ".help" for more information.
> await require('fs/promises').rm('a/b/../.', { recursive: true, force: true })
Uncaught [Error: EINVAL: invalid argument, rmdir 'a/b/../.'] {
  errno: -22,
  code: 'EINVAL',
  syscall: 'rmdir',
  path: 'a/b/../.'
}

Verify that nothing was removed:

$ tree
./
└── a/
    └── b/
        └── c/
            └── d/

Attempt to delete synchronously:

> require('fs').rmSync('a/b/../.', { recursive: true, force: true })
undefined

It was (mostly?) removed:

$ tree
./
└── a/

The weird thing is that a/b/../. should resolve to just a, so it's weird that it only deletes up to b. It's almost as if the rmSync method is coalescing /../. into just /.

Also, if the . is not the last item, then it seems to be fine? a/b/.././b deletes the b folder, and a/b/.. deletes just b, but not a.

At least, it seems like the sync and asynchronous methods should either both fail, or both succeed, with the same error.

How often does it reproduce? Is there a required condition?

every time, see repro steps above

What is the expected behavior? Why is that the expected behavior?

sync and asynchronous rm methods should fail and succeed in the same way on the same input.

What do you see instead?

Some cases where rmSync succeeds, and fs/promises.rm fails.

Additional information

I have a fix that I could land in the upstream rimraf library, and I'd of course be happy to send a PR to node to bring it back into alignment, since there have also been some improvements in performance and Windows re

GitHub Labels

confirmed-bugfs