Git Diff Files

git-diff-files.sh

#!/usr/bin/env bash

main() {
  while getopts ':e:c:h:' opt
  do
    case $opt in
      e) extention="$OPTARG" ;;
      c) command="$OPTARG" ;;
      h) commit_hash="$OPTARG" ;;
      *) echo "Wrong option: ${1}." exit 1;;
    esac
  done

  diff_files "${extention}" "${commit_hash}" "${command}"

  if [ $OPTIND -eq 1 ]; then echo "No flag option was passed."; fi
}

diff_files() {
  extension="${1}"
  commit_hash="${2}"
  command="${3}"

  if [[ -z "${commit_hash}" ]]; then
    list=$(git diff-index --name-only HEAD | grep -E "(.*)\\.${extension}$" | xargs)

    run_command "${list}" "${extension}" "${command}"
  else
    list=$(git show --pretty="" --name-only "${commit_hash}" | grep -E "(.*)\\.${extension}$" | xargs)

    run_command "${list}" "${extension}" "${command}"
  fi
}

filter_deleted_files() {
  filtered_list="${1}"
  deleted_files=($(git diff-index HEAD --diff-filter=D --summary --name-only))

  for file in "${deleted_files[@]}"; do
    filtered_list=("${filtered_list[@]/$file}")
  done

  echo "${filtered_list[@]/deleted_files}"
}

run_command() {
  list=$(filter_deleted_files "${1}")
  extension="${2}"
  command="${3}"

  if [[ -z "${extension}" ]]; then
    echo "No extention provided."
  else
    if [[ -z "${list}" ]]; then
      echo "No .${extension} files changed."
    else
      eval "${command} ${list}"
      exit $?
    fi
  fi
}

main "${@}"