pre-commit hook for Git on a system running OSX (Mac)

OS-Mac-git-pre-commit-hook

#!/bin/sh
 
if git rev-parse --verify HEAD >/dev/null 2>&1; then
    against=HEAD
else
    # put the first changeset hash value in your project here (I think)
    against=facf87a3fa1c853a7dd8dde8cba32e1fc8fde3ea
fi
 
for FILE in `git diff-index --name-status $against -- | cut -c3-` ; do
    # Check if the file contains 'debugger'
    if [ "grep 'debugger' $FILE" ]
    then
        echo $FILE ' contains debugger!'
        exit 1
    fi
done
exit 

On line 7, you'll need against=4b825dc642cb6eb9a060e54bf8d69288fbee4904 instead. This is a magic hash present in all git repositories. Just google the hash and you'll see

If you add the --cached flag to your git diff-index call, it'll only run against files that are staged for commit, which is generally what I think you want.

On my system, if [ "grep 'debugger' $FILE" ] always evaluates to true. Changing it to if grep -q 'debugger' "$FILE" fixes that.