String-check pre-commit hook

pre-commit

#!/bin/sh

# Pre commit hook that prevents FORBIDDEN code from being commited.
# Add unwanted code to the FORBIDDEN array as necessary, single-space separated.
# Ensure executable: "chmod +x .git/hooks/pre-commit"

FILES_PATTERN='\.(rb|js|coffee|txt)(\..+)?$'
FORBIDDEN=( \.only )
FAILED=false

for i in "${FORBIDDEN[@]}"
do

  git diff --cached --name-only | \
    grep -E $FILES_PATTERN | \
    GREP_COLOR='4;5;37;41' xargs grep --color --with-filename -n '${i}' && \
    echo 'COMMIT REJECTED Found'  $i 'references. Please remove them before commiting' && FAILED=true
done

if [ "$FAILED" = true ] ; then
    exit 1
fi

exit

FORBIDDEN is a regex... plan accordingly with your periods.