Pre-commit script for our rails app

pre-commit

#!/usr/bin/env ruby

require 'rubocop'
require 'english'

ADDED_OR_MODIFIED = /A|AM|^M/

# to prevent code injection: system is a dangerous call
def raise_single_quote_error
  raise ArgumentError, 'Single quotes are not allowed in filenames here.'
end

def extract_file_name(file_name_with_status)
  file_name_array = file_name_with_status.strip.split(' ')
  file_name_array.shift
  fname = file_name_array.join(' ')
  fname[0] = '' if fname[0] == '"'
  fname[fname.length - 1] = '' if fname[fname.length - 1] == '"'
  raise_single_quote_error if fname.include?("'")
  fname
end

changed_files =
  `git status --porcelain`
  .split(/\n/)
  .select { |file_name_with_status| file_name_with_status =~ ADDED_OR_MODIFIED }
  .map { |file_name_with_status| extract_file_name file_name_with_status }
  .select { |file_name| File.extname(file_name) =~ /.rb/ }
  .join("' '")

unless changed_files.empty?
  system("bundle exec rubocop --fail-level A -a '#{changed_files}'")
  system("bundle exec erblint --lint-all -a '#{changed_files}'")
end

exit $CHILD_STATUS.to_s[-1].to_i

Installation

• copy the contents of this file into .git/hooks/pre-commit
• chmod 755 .git/hooks/pre-commit

Usage

This will trigger before every commit and prevent the commit from happening if something needs to be done. rubocop tries to automatically fix things for you. If you want to skip this, use the -n flag.