Question:
I need some help with a Bash script that will automatically add the git’s branch name as a hash in commit messages.
Answer:
Use the prepare-commit-msg or commit-msg githook.
There are examples already in your PROJECT/.git/hooks/ directory.
As a security measure, you will have to manually enable such a hook on each repository you wish to use it. Though, you can commit the script and copy it on all clones into the .git/hooks/ directory.