`cp` and `cpSync` incorrectly handle existing dest symlinks

[dario-piotrowicz]

Version

v24.1.0

Platform

Linux Laptop-16-AMD-Ryzen-7040-Series 6.8.0-60-generic #63-Ubuntu SMP PREEMPT_DYNAMIC Tue Apr 15 19:04:15 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux

Subsystem

fs

What steps will reproduce the bug?

Run the following code:

"use strict";

const fs = require("node:fs");
const path = require("node:path");

// cleans up test and dest directories
fs.rmSync("./tmp/test", { recursive: true, force: true });
fs.rmSync("./tmp/dest", { recursive: true, force: true });

// prepares the test directory
fs.mkdirSync("./tmp/test", { recursive: true });

// in the test directory creates a source.txt file and a link.txt symlink that points to the source.txt file
fs.writeFileSync("./tmp/test/source.txt", "test content");
fs.symlinkSync(path.resolve("./tmp/test/source.txt"),"./tmp/test/link.txt");

// call cpSync
fs.cpSync("./tmp/test", "./tmp/dest", { recursive: true });
// call cpSync again (this so with dest already existing/populated)
fs.cpSync("./tmp/test", "./tmp/dest", { recursive: true });

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

the issue can always be reproduced and it does not require a specific condition

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

I believe that the second cpSync call should not throw any error, but the existing symlink files should be skipped unless force is set to false and errorOnExist is true, in such case an EEXIST error should be thrown instead

What do you see instead?

The second cpSync call throws an ERR_FS_CP_EINVAL error

Additional information

• The ERR_FS_CP_EINVAL error is thrown even when force is being used (and the dest file is not overridden).

• This applies both to cp and cpSync

  `cp` reproduction

  "use strict";
  
  const fs = require("node:fs");
  const path = require("node:path");
  
  fs.rmSync("./tmp/test", { recursive: true, force: true });
  fs.rmSync("./tmp/dest", { recursive: true, force: true });
  
  fs.mkdirSync("./tmp/test", { recursive: true });
  
  fs.writeFileSync("./tmp/test/source.txt", "test content");
  fs.symlinkSync(path.resolve("./tmp/test/source.txt"),"./tmp/test/link.txt");
  
  fs.cp("./tmp/test", "./tmp/dest", { recursive: true }, (err) => {
      if(err) throw err;
  
      fs.cp("./tmp/test", "./tmp/dest", { recursive: true }, (err) => {
          if (err) throw err;
      });
  });

• setting dereference to true seems to fix the issue, however I am not sure if dereferencing is actually taking place since the symlinks are copied as such and not as the files they point to (which I think is the expected behavior? 🤔)

[dario-piotrowicz]

cc. @nodejs/fs 🙂