ESLintの設定でうっかり新しい記法が許されていた場合に警告する

limit-eslint-target-version-to-es2017.sh

#! /bin/sh

target_version=2017

main () {
  config_file=$1
  
  if [ -z "$config_version" ]; then
    cat <<EOD
eslint config file not specified

ex) ./limit-ecma-version.sh .eslintrc.js
EOD
  else
    echo "start checking with " $config_file
    do_check $config_file
  fi
}

do_check () {
  config_file=$1

  yarn run -s eslint --print-config $config_file | jq .env | awk -v target_version=$target_version '{
  if (match($0, /es([0-9]+)/) && /true/) {
    version = substr($0, RSTART + 2, RLENGTH - 2)
    if (version + 0 > target_version) {
      print "CAUTION ! this config may break not-most-modern browsers."
      print
      exit 1
    }
  }
}
'
}

main $1