nodejs　get directory tree

getDirectoryTree.js

function getDirectoryTree(start_dirpath, {dir = true, file = true, max_depth = -1, flatten = false} = {}){
	const tree = {}
	dir = !!dir
	file = !!file
	max_depth = ~~max_depth
	flatten = !!flatten
	
	!function recur(dirpath, store, depth){
		if(depth > max_depth && max_depth >= 0) return
		
		for(const name of fs.readdirSync(dirpath)){
			const realpath = fs.realpathSync(dirpath + "/" + name);
			if(fs.statSync(realpath).isDirectory()){
				if(!dir) continue
				
				const subtree = {"": realpath}
				store[name] = subtree
				recur(realpath, subtree, depth + 1)
			}else{
				if(!file) continue
				
				store[name] = realpath
			}
		}
	}(start_dirpath, tree, 1)
	
	if(flatten){
		const paths = []
		
		!function seek(node){
			Object.values(node).forEach(e => {
				if(typeof e === "object"){
					seek(e)
				}else{
					paths.push(e)
				}
			})
		}(tree)
		
		return paths
	}
	
	return tree
}