Merging subdirectories while moving files using "mv"

The command line executable mv cannot merge subdirectories. It will fail with messages like mv: cannot move: Directory not empty

The following is a bash script to move all contents of "SRC" directory to "DEST" directory. The usage is ./merge-mv SRC DEST

#!/usr/bin/env bash
set -eu
shopt -s globstar
shopt -s dotglob
shopt -s nullglob

src_path=$(readlink -f "$1")
dst_path=$(readlink -f "$2")
cd "${src_path}"

for dir in **/; do
	if [[ ! -e "${dst_path}/${dir}" ]]; then
		mv -nv "${dir}" "${dst_path}/${dir}"
		continue
	fi
	if [[ ! -d "${dst_path}/${dir}" ]]; then
		>&2 echo "Cannot merge '${src_path}/${dir}' with '${dst_path}/${dir}'"
		exit 1
	fi
done

for dir in **/; do
	for file in "${dir}"*; do
		if [[ -d "${file}" ]]; then
			continue
		fi
		mv -nv "${file}" "${dst_path}/${dir}"
	done
done

find . -mindepth 1 -type d -delete

If there is a conflict, the script will not overwrite existing file in DESR and let the conflicting file in SRC stay as-is. Feedbacks are welcome (contact me at https://mastodon.jangho.io/@jangho)