Black pre-commit git hook persistent fail status

[felipepenha]

When trying to commit, pre-commit runs and alters python files. When you try running git commit again, it fails yielding a warning

[WARNING] Unstaged files detected.
[INFO] Stashing unstaged files ...

This issue was detected during a Twitch live stream. The solution was found minutes later, and will be posted in the comments below.

[felipepenha]

The solution is realizing that due to changes made by black, it is necessary to repeat the operation git add. Thus, the workflow is as follows:

$ git add [file]
$ git commit -m "[message]"
black........................Failed
reformatted [file]
All done! ✨ 🍰 ✨
1 file reformatted.
$ git add -u
$ git commit -m "[message]"
black........................Passed
``
`git add -u` only adds currently tracked files (which have been modified) to the staging area and also checks if they have been deleted (if yes, they are removed from staging area). This means that it does not stage new files.

[felipepenha]

Related issues in the pre-commit repo:
pre-commit/pre-commit#806
pre-commit/pre-commit#747
pre-commit/pre-commit#879

In stackoverflow, including a response from the author of pre-commit:
https://stackoverflow.com/questions/58398995/black-as-pre-commit-hook-always-fails-my-commits

[felipepenha]

To Do: find out whether it is feasible to include git add -u in the hook itself.

[felipepenha]

Solution for pre-commit failing with black Issue #17: sequence of commands defined via make add-commit.