Pre-commit hook for git with phpcs and phpcbf (auto-correct obvious violations)

pre-commit

#!/bin/sh
 
PROJECT=`php -r "echo dirname(dirname(dirname(realpath('$0'))));"`
STAGED_FILES_CMD=`git diff --cached --name-only --diff-filter=ACMR HEAD | grep \\\\.php`
 
# Determine if a file list is passed
if [ "$#" -eq 1 ]
then
	oIFS=$IFS
	IFS='
	'
	SFILES="$1"
	IFS=$oIFS
fi
SFILES=${SFILES:-$STAGED_FILES_CMD}
 
echo "Checking PHP Lint..."
for FILE in $SFILES
do
	php -l -d display_errors=0 $PROJECT/$FILE
	if [ $? != 0 ]
	then
		echo "Fix the error before commit."
		exit 1
	fi
	FILES="$FILES $PROJECT/$FILE"
done
 
if [ "$FILES" != "" ]
then
	echo "Running Code Sniffer..."
	./bin/phpcs --standard=PSR2 --encoding=utf-8 -n -p $FILES
	if [ $? != 0 ]
	then
		echo "Coding standards errors have been detected. Running phpcbf..."
		./bin/phpcbf --standard=PSR2 --encoding=utf-8 -n -p $FILES
		git add $FILES
		echo "Running Code Sniffer again..."
		./bin/phpcs --standard=PSR2 --encoding=utf-8 -n -p $FILES
		if [ $? != 0 ]
		then
			echo "Errors found not fixable automatically"
			exit 1
		fi
	fi
fi
 
exit $?

• Assumed that you have both phpcs and phpcbf in bin/ folder. Best practice is to use the dedicated package for phpcs: squizlabs/PHP_CodeSniffer
• Copy / Paste that script in your .git/hooks folder and set correct rights to your new file:

chmod +x .git/hooks/pre-commit

For Laravel, I had to change the command in the script to particular phpcs and phpcbf file inside vendor/bin folder.

I recommend using xargs together with phpcbf and phpcs in case there is a really large number of files. Happened to me, when switching between code styles automatically. This will break the script with "Too many arguments" error:

echo $FILES | xargs --max-procs=4 ./bin/phpcbf -n -p

--max-procs=4 forces xargs to return no error code even if phpcs found some (MacOS Big Sur)

then leave it out :-)
I would always do a phpcs after phpcbf, because you might only want to have an error code thrown when not all files could be fixed automatically and no error code when it was automatically fixed.