git hook for commit-msg to use ESLint as a soft guard of code quality (lets things pass if the committer is committed to committing)

commit-msg

#!/bin/bash

# Uses ESLint as a soft guard of code quality for your repo
# allows commits to go through if re-attempted within a pre-set interval
# copy to .git/hooks/commit-msg to have things work

# Based on: https://gist.github.com/wesbos/8aec9d2ff7f7cf9dd65ca2c20d5dfc23

PRESET_TIME_INTERVAL=60

LAST_RUN_DATE_FILE="$HOME/.eslint.commit-msg-hook.last-failed-run"
if [ ! -f $LAST_RUN_DATE_FILE ] ; then
	echo "0" > $LAST_RUN_DATE_FILE
fi

# because somehow /usr/local/bin might not be on the path
PATH=$PATH:/usr/local/bin:/usr/local/sbin

CURR_EPOCH=$(date +%s)
LAST_RUN_EPOCH=$(cat $LAST_RUN_DATE_FILE)
TIME_DIFFERENCE_IN_SEC=$(expr $CURR_EPOCH - $LAST_RUN_EPOCH)

files=$(git diff --cached --name-only | grep '\.jsx\?$')

# Prevent ESLint help message if no files matched
if [[ $files = "" ]] ; then
  exit 0
fi

failed=0
for file in ${files}; do
  git show :$file | eslint $file
  if [[ $? != 0 ]] ; then
    failed=1
  fi
done;


if [[ $failed != 0 ]] ; then
  echo "💩💩💩 ESLint failed."
  if [ "$TIME_DIFFERENCE_IN_SEC" -ge $PRESET_TIME_INTERVAL ]; then
    echo "🚫🚫🚫 git commit denied!"
    echo "Attempt to commit again within $PRESET_TIME_INTERVAL seconds and the commit will succeed.";
    echo "... and please ensure that there are no syntax errors if you do so.";
    date +%s > $LAST_RUN_DATE_FILE
    exit $failed
  else
    echo "Current commit attempt is within $PRESET_TIME_INTERVAL seconds of last failed attempt.";
    echo "😡😡😡 git commit reluctantly allowed.";
	  echo "0" > $LAST_RUN_DATE_FILE
  fi
fi