std/fs: `walk` not found error is not `Deno.errors.NotFound`

[lucacasonato]

If you pass a path to walk that does not exist on the fs, the returned promise rejects with an Error, not a Deno.errors.NotFound.

[getspooky]

I tried to reproduce the bug but it return Deno.errors.NotFound

import { walk } from "https://deno.land/std@0.108.0/fs/mod.ts";

try {
  for await (const entry of walk("./deno")) {
    console.log(entry.path);
  }
} catch (error) {
  console.log(error instanceof Deno.errors.NotFound);
}

The result:

true

My configuration:

deno 1.14.0 (release, x86_64-unknown-linux-gnu)
v8 9.4.146.15
typescript 4.4.2

[zhangyuannie]

Related #1216 which contains steps to reproduce.

After some investigations, I believe it is due to the same underlying issue: Rust std::fs categorise Not a directory (ENOTDIR) error as Other instead of NotFound. That error then get propagated from lstat/stat op in Deno.

Worth noting that a new NotADirectory is available in Rust on nightly right now which will help with the issue.

So although far form ideal, it is expected that Deno.errors.NotFound is not returned from walk.

[iuioiua]

I got the same as @getspooky. Is this still an issue?

[kt3k]

Seems like not an issue. Let's close

[mikeatbuilder]

@lucacasonato @kt3k there's a related TODO in the fresh code here just FYI:
https://github.com/denoland/fresh/blob/b12867a5823a338b318b14f1b6e399e61064dce9/src/server/context.ts#L249
and here:
https://github.com/denoland/fresh/blob/b12867a5823a338b318b14f1b6e399e61064dce9/src/dev/mod.ts#L44

[kt3k]

@mikeatbuilder Thanks for the input. Sounds interesting. I think we should try to remove that workaround in fresh as this was a non issue

[lucacasonato]

@kt3k Have you tried on Linux. This may be fine on macOS, but it's still broken on Linux.

[kt3k]

Ok. I'll take a look

[kt3k]

It still seems NotFound in ubuntu

ubuntu@ip-172-31-255-98:~$ ls
main.js
ubuntu@ip-172-31-255-98:~$ cat main.js 
import { walk } from "https://deno.land/std@0.153.0/fs/mod.ts";

try {
  for await (const entry of walk("./deno")) {
    console.log(entry.path);
  }
} catch (error) {
  console.log(error instanceof Deno.errors.NotFound);
}

ubuntu@ip-172-31-255-98:~$ deno -V
deno 1.25.0
ubuntu@ip-172-31-255-98:~$ deno run -A main.js 
true
ubuntu@ip-172-31-255-98:~$ cat /etc/lsb-release 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=22.04
DISTRIB_CODENAME=jammy
DISTRIB_DESCRIPTION="Ubuntu 22.04 LTS"

[kt3k]

If I put a file of the same name of walk entrypoint, then I get Error: Not a directory (os error 20), readdir './deno'. This might be the actual problem in the above line in fresh?

[iuioiua]

Is this still an issue on Linux?