vfs: recursive mkdir does not follow symlinked intermediate directories

[trivikr]

Version

main

Platform

macOS 26.5.0

Subsystem

vfs

What steps will reproduce the bug?

import vfs from 'node:vfs';

const fs = vfs.create({ emitExperimentalWarning: false });

fs.mkdirSync('/target');
fs.symlinkSync('/target', '/link');

try {
  fs.mkdirSync('/link/subdir', { recursive: true });
  console.log('/target/subdir exists:', fs.existsSync('/target/subdir'));
} catch (err) {
  console.log('threw:', err.code);
}

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

Always

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

/target/subdir exists: true

Native recursive mkdir follows symlinked intermediate path components, so creating through /link/subdir should create subdir inside /target.

What do you see instead?

throws ENOTDIR

The recursive mkdir loop checks the symlink entry itself with entry.isDirectory() instead of resolving the intermediate symlink to its directory target.

Additional information

fs equivalent

import fs from 'node:fs';
import os from 'node:os';
import path from 'node:path';

const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'mkdir-symlink-'));

const target = path.join(dir, 'target');
const link = path.join(dir, 'link');

fs.mkdirSync(target);
fs.symlinkSync(target, link);

try {
  fs.mkdirSync(path.join(link, 'subdir'), { recursive: true });
  console.log('target/subdir exists:', fs.existsSync(path.join(target, 'subdir')));
} catch (err) {
  console.log('threw:', err.code);
}

Output

target/subdir exists: true