Sample pre-commit ruby script

bin_pre-commit

#!/usr/bin/env ruby

require "rubygems"
require "bundler/setup"

lib_dir = File.expand_path(File.join(File.dirname(__FILE__), "..", "lib"))
$LOAD_PATH << lib_dir unless $LOAD_PATH.include?(lib_dir)

# NOTE: https://github.com/piotrmurach/tty-command
require "tty-command"
# NOTE: https://github.com/piotrmurach/tty-logger
require "tty-logger"
# NOTE: https://github.com/piotrmurach/tty-prompt
require "tty-prompt"

require "bundler/audit/cli"
require "brakeman"
require "rubocop"
require "benchmark"

logger = TTY::Logger.new do |config|
  config.level = ENV["DEBUG"].nil? ? :info : :debug
end

class << logger
  def <<(msg)
    msg.each_line do |line|
      debug(line.rstrip)
    end
  end
end

cmd = TTY::Command.new(output: logger)
prompt = TTY::Prompt.new

STDIN.reopen("/dev/tty")
exit 0 unless prompt.yes?("Run checks?", default: false)

cmd.run!("bundle audit update -q")
out, err = cmd.run("bundle audit")
puts(out)
exit(1) if err

result = Brakeman.run "."
puts(result.warnings)
puts(result.errors)
exit(1) if err

rb_changes = !cmd.run!("git diff --name-only HEAD | grep .rb").failure?
if rb_changes
  rubocop_cli = RuboCop::CLI.new
  result = rubocop_cli.run
  exit result unless result == 0
end

exit 0

package.json

{
  "husky": {
    "hooks": {
      "pre-commit": "bin/pre-commit",
      "pre-push": "bin/pre-push"
    }
  },
  "dependencies": {
    "@rails/webpacker": "^4.0.7"
  },
  "devDependencies": {
    "husky": "^4.2.3",
    "webpack-dev-server": "^3.8.0"
  }
}