Run rubocop via Docker Compose as a git pre-commit hook

pre-commit

#!/bin/sh

# Get a list of all staged Ruby (.rb) files
RUBY_FILES=$(git diff --cached --name-only --diff-filter=ACM | grep '\.rb$')

# If there are no Ruby files, skip the check
if [ -z "$RUBY_FILES" ]; then
  exit 0
fi

# Run Rubocop on the staged Ruby files
echo "Running Rubocop on staged Ruby files..."
docker compose exec -T web bundle exec rubocop -P $RUBY_FILES

# Check if Rubocop passed
if [ $? -ne 0 ]; then
  echo "Rubocop detected problems, aborting commit."
  exit 1
fi

# If we got here, everything is OK
echo "Rubocop checks passed."
exit 0

Instructions

Setup

1. cd your/repo
2. touch .git/hooks/pre-commit
3. chmod +x .git/hooks/pre-commit
4. Copy the contents of the pre-commit file below into .git/hooks/pre-commit

Test

1. docker compose up web
2. Make a change in a .rb file that causes a rubocop warning
3. git add the file
4. git commit -m "test"

You should see the output of rubocop and it should prevent the commit from going through