mass-rename files and change contents with sed

mass-rename

#!/usr/bin/env bash
[[ "${BASH_VERSINFO[0]}" -ge 4 ]] || {
  echo >&2 'Requires bash >= 4'
  exit 1
}
set -Eeuo pipefail
[ -z "${DEBUG-}" ] || set -x

if [ "$#" = 0 ]; then
  cat >&2 << 'USAGE'
  
  Usage: mass-rename {sed expression(s)} [directory]
  
  The directory itself is *not* renamed.
  
  NO WARRANTIES! Have tested backups before proceeding. 
  
USAGE
  exit 1
fi

if [ "${2-}" ]; then
  cd "$2"
fi

case "$OSTYPE" in
  darwin*|freebsd*|netbsd*|openbsd*)
    inplace_replace() {
      LC_ALL=C sed -i '' "$@"
    }
    ;;
  *)
    inplace_replace() {
      sed -i "$@"
    }
esac

if git rev-parse --is-inside-work-tree &>/dev/null; then
  if [ "$(git status --porcelain)" ]; then
    echo >&2 'Git working directory unclean, aborting mass-rename'
    exit 1
  fi
  trap 'e=$?; trap - EXIT; rm -rf "$T"; exit $e' EXIT
  T="$(mktemp -d)"
  all="$T/all"
  ignores="$T/ignores"
  find -E . -mindepth 1 ! -iregex '.*/\.git(/.*)?' | sort >"$all"
  git check-ignore --stdin <"$all" >"$ignores" || true
  readarray -t src_files < <(comm -23 "$all" "$ignores")
else
  readarray -t src_files < <(find -E . -mindepth 1 | sort)
fi

delete_list=()

for src in "${src_files[@]}"; do
  src=${src#\./}

  if [ ! -d "$src" ] && file -b "$src" | grep -q text; then
    inplace_replace "$1" "$src"
  fi

  dest=$(sed "$1" <<<"$src")
  abs_dest="$PWD/$dest"
  [ "$src" != "$dest" ] || continue
  if [ -d "$src" ] ; then
    if [ "$(readlink -f "$src")" != "$(readlink -f "$abs_dest")" ]; then
      delete_list=("$src" "${delete_list[@]}")
      mv -v "$src" "$dest"
      ln -s "$abs_dest" "$src"
    fi
  else
    mv -v "$src" "$dest"
  fi
done

if [ "${#delete_list[@]}" != 0 ]; then
  rm -f "${delete_list[@]}"
fi