git-fix-author-committer - Apply filter-branch --commit-filter easily

git-fix-author-committer

#!/bin/bash
#
# Apply filter-branch --commit-filter easily
#
# Author: Yuki <paselan@gmail.com>
# License: MIT License
#

PROGNAME=$(basename $0)
SUBCMDNAME=${PROGNAME#git-}

usage() {
  echo "usage: git $SUBCMDNAME [options] [rev-list options]"
  echo
  echo "  --old-email=[EMAIL]   old email address"
  echo "  --new-name=[NAME]     new user name"
  echo "  --new-email=[EMAIL]   new email address"
  echo
  exit 1
}

for OPT in "$@"
do
  case "$OPT" in
    '-h'|'--help' )
      usage
      exit 1
      ;;
    '--old-email='* )
      OLD_EMAIL=${1#--old-email=}
      if [[ -z "$OLD_EMAIL" ]]; then
        echo "option requires an argument -- --old-email" 1>&2
        exit 1
      fi
      shift 1
      ;;
    '--old-email' )
      if [[ -z "$2" ]] || [[ "$2" =~ ^-+ ]]; then
        echo "option requires an argument -- $1" 1>&2
        exit 1
      fi
      OLD_EMAIL="$2"
      shift 2
      ;;
    '--new-name='* )
      NEW_NAME=${1#--new-name=}
      if [[ -z "$NEW_NAME" ]]; then
        echo "option requires an argument -- --new-name" 1>&2
        exit 1
      fi
      shift 1
      ;;
    '--new-name' )
      if [[ -z "$2" ]] || [[ "$2" =~ ^-+ ]]; then
        echo "option requires an argument -- $1" 1>&2
        exit 1
      fi
      NEW_NAME="$2"
      shift 2
      ;;
    '--new-email='* )
      NEW_EMAIL=${1#--new-email=}
      if [[ -z "$NEW_EMAIL" ]]; then
        echo "option requires an argument -- --new-email" 1>&2
        exit 1
      fi
      shift 1
      ;;
    '--new-email' )
      if [[ -z "$2" ]] || [[ "$2" =~ ^-+ ]]; then
        echo "option requires an argument -- $1" 1>&2
        exit 1
      fi
      NEW_EMAIL="$2"
      shift 2
      ;;
    '--'|'-' )
      shift 1
      param+=( "$@" )
      break
      ;;
    -*)
      echo "illegal option -- '$(echo $1 | sed 's/^-*//')'" 1>&2
      exit 1
      ;;
    *)
      if [[ ! -z "$1" ]] && [[ ! "$1" =~ ^-+ ]]; then
        #param=( ${param[@]} "$1" )
        param+=( "$1" )
        shift 1
      fi
      ;;
  esac
done

if [ -z "$OLD_EMAIL" ]; then
  echo -n "Old email> "
  read OLD_EMAIL
  [ -n "$OLD_EMAIL" ] || exit 1
fi

if [ -z "$NEW_NAME" ]; then
  echo -n "New name> "
  read NEW_NAME
  [ -n "$NEW_NAME" ] || exit 1
fi

if [ -z "$NEW_EMAIL" ]; then
  echo -n "New email> "
  read NEW_EMAIL
  [ -n "$NEW_EMAIL" ] || exit 1
fi

export OLD_EMAIL NEW_NAME NEW_EMAIL

git filter-branch -f --commit-filter '
if [ "$GIT_AUTHOR_EMAIL" = "$OLD_EMAIL" ]; then
  GIT_AUTHOR_NAME=$NEW_NAME
  GIT_AUTHOR_EMAIL=$NEW_EMAIL
fi
if [ "$GIT_COMMITTER_EMAIL" = "$OLD_EMAIL" ]; then
  GIT_COMMITTER_NAME=$NEW_NAME
  GIT_COMMITTER_EMAIL=$NEW_EMAIL
fi
git commit-tree "$@"
' "${param[@]}"