pre-commit.sh

#!/bin/bash

chruby 2.7.0
export RUBYOPT=-W:no-deprecated

# Install all gem dependencies
bundle install

# Just to prevent showing many "error" messages
dirty_bit=0

# Run rubocop
rubocop -a
last_command_ret_code=$?

if [ $last_command_ret_code -eq 0 ]; then
  # Run unit tests
  bundle exec rails test
  last_command_ret_code=$?
else
  echo "RUBOCOP OFFENSES PREVENTED ME FROM COMMITTING..."
  dirty_bit=1
fi

if [ $last_command_ret_code -eq 0 ]; then
  # Prepare to run system tests
  yarn build-for-tests

  # Run system tests
  bundle exec rails test:system
  last_command_ret_code=$?
elif [ $dirty_bit -eq 0 ]; then
  echo "UNIT TESTS FAILURES/ERRORS PREVENTED ME FROM COMMITTING..."
  dirty_bit=1
fi

if [ $last_command_ret_code -eq 0 ]; then
  echo "ALL GOOD. COMMITTING..."
elif [ $dirty_bit -eq 0 ]; then
  echo "SYSTEM TESTS FAILURES/ERRORS PREVENTED ME FROM COMMITTING..."
fi

# Return the last "error" code if any
exit $last_command_ret_code

My suggestion:

- rubocop -a
- NUM_OFFENSES=`rubocop -a | grep "offenses detected" | awk {'print $4'}`
+ NUM_OFFENSES=`rubocop -a | egrep 'offenses? detected' | perl -e '($d,undef,$c)=<STDIN>=~m/\s(\S*)\soffenses?\sdetected(,\s(\S*)\soffenses?\scorrected)?/;print"$d"eq"no"||"$d"eq"$c"?0:$d-$c;'`

just one pass of rubocop

The idea is no offenses => 0 N offenses detected, K offenses corrected => N-K

Also be careful with this condition: if [ $NUM_FAILS -ne 0 ] cause when its true the script exits without doing a git stash pop -q

At Codegram we are using https://github.com/typicode/husky to manage git hooks. You can include the hooks in the package json like this

{
  "scripts": {
    "pre-commit": "bundle exec rubocop -a"
  },
  "lint-staged": {
    "*.rb": [
      "bundle exec rubocop -a"
    ]
  }
}

The lint-staged package is optional but it is very useful to run the command just for the files that have been changed.

Nice, I'll check Husky out. 😄