vfs: recursive mkdir returns backing-directory path for RealFSProvider

[trivikr]

Version

main

Platform

All

Subsystem

vfs

What steps will reproduce the bug?

import { mkdtempSync, mkdirSync, existsSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { join } from 'node:path';
import { create, RealFSProvider } from 'node:vfs';

const root = mkdtempSync(join(tmpdir(), 'vfs-'));
const myVfs = create(new RealFSProvider(root));
const mountPoint = myVfs.mount();

const asked = join(mountPoint, 'a/b');
const created = mkdirSync(asked, { recursive: true });
console.log('created:', created);
console.log('existsSync(created):', existsSync(created));
console.log('existsSync(asked):', existsSync(asked));

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

Always

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

created should be <mountPoint>/a and pass fs.existsSync()

What do you see instead?

created: /dev/null/vfs/0/var/folders/42/54jl1_3x4hz06cf7bc_kzd4h0000gn/T/vfs-MMktQW/a
existsSync(created): false
existsSync(asked): true

created is <mountPoint>/<backing-root>/a — the absolute backing-directory path leaks through — and fs.existsSync(created) is false

Additional information

No response