Black reformats entire virtual environment when named env with pathspec==0.10.0

[jnhyperion]

Describe the bug

When using black and virtualenv, black try to reformat entire virtual env folder, which cause heavy process execution and hang very long.

To Reproduce
For example, take this code:

mkdir myfolder

cd myfolder

virtualenv env

source env/bin/activate

pip install black

pip list

Package           Version
----------------- -------
black             22.8.0
click             8.1.3
mypy-extensions   0.4.3
pathspec          0.10.0
pip               22.2.2
platformdirs      2.5.2
setuptools        63.4.3
tomli             2.0.1
typing_extensions 4.3.0
wheel             0.37.1

black . --check --diff

then black will try to check all the env folder.

this issue is caused by the library pathspec 0.10.0, and black does not lock the version, looks like pathspec already fix the bug in 0.10.1.

but for black, does it need to lock, or force skip this buggy pathspec version, to avoid this fatal error

[JelleZijlstra]

If you tell Black to format everything in a directory, it will; it can't magically determine that the folder contains a virtual env. We exclude a few common names for virtual envs by default, but env is not among them. You can use the --exclude or --extend-exclude option to exclude directories.

Can you clarify what you think the bug is in pathspec?

[ichard26]

Black doesn't actually include env in its default excludes, I think it's probably a good idea to include it even if it's a less common virtual environment name. Not sure why upgrading pathspec would change black's behaviour, it shouldn't be coming into play here as there's no .gitignore file anywhere.

Are there situations where excluding env by default would be a problem? @JelleZijlstra

[JelleZijlstra]

env is a perfectly plausible name for a folder containing actual code that you want to be formatted. It would be an unpleasant experience for a user to find out that Black silently skips a directory they want to get formatted.

[jnhyperion]

in the virtual env folder env, it will automatically contains .gitignore

# created by virtualenv automatically
*

which I think will be recogonized by black right?

in my case, if I upgrade pathspec to 0.10.1, this issue will disappear.

the bug is here: cpburnz/python-pathspec#62

[ichard26]

cpburnz/python-pathspec#62 ahhh I see, sounds like we should ask upstream to yank this version since it might cause a lot of grief.

[ionite34]

The env directory not ignored issue seems to only occur with pathspec version 0.10.0, and not in 0.9.0 nor the newest 0.10.1 version. Probably related to cpburnz/python-pathspec#62

[ichard26]

I've asked upstream to yank pathspec 0.10.0, let's see if they're open to it, otherwise, I'd be open to banning the faulty version on Black's end.

[ichard26]

And pathspec 0.10.0 has been yanked: https://pypi.org/project/pathspec/0.10.0/