python walk_up - like os.walk, only works its way up instead of down

walk_up.py

#!/bin/env python

"""
os.walk is an awesome generator.
However, I needed the same functionality,
only I wanted to walk 'up' the
directory tree.

This allows seaching for files
in directories directly above
a given directory.
"""


import os
from os import path

def walk_up(bottom):
	""" 
	mimic os.walk, but walk 'up'
	instead of down the directory tree
	"""

	bottom = path.realpath(bottom)

	#get files in current dir
	try:
		names = os.listdir(bottom)
	except Exception as e:
		print e
		return


	dirs, nondirs = [], []
	for name in names:
		if path.isdir(path.join(bottom, name)):
			dirs.append(name)
		else:
			nondirs.append(name)

	yield bottom, dirs, nondirs

	new_path = path.realpath(path.join(bottom, '..'))
	
	# see if we are at the top
	if new_path == bottom:
		return

	for x in walk_up(new_path):
		yield x

if __name__ == '__main__':
    # tests/demos

    #print all files and directories
    # directly above the current one
    for i in walk_up(os.curdir):
        print i

    # look for a TAGS file above the
    # current directory
	for c,d,f in walk_up(os.curdir):
		if 'TAGS' in f:
			print c
			break

	

#python3 version

import os
from os import path

def walk_up(bottom):
    """ 
    mimic os.walk, but walk 'up'
    instead of down the directory tree
    """

    bottom = path.realpath(bottom)

    #get files in current dir
    try:
        names = os.listdir(bottom)
    except Exception as e:
        print(e)
        return


    dirs, nondirs = [], []
    for name in names:
        if path.isdir(path.join(bottom, name)):
            dirs.append(name)
        else:
            nondirs.append(name)

    yield bottom, dirs, nondirs

    new_path = path.realpath(path.join(bottom, '..'))
    
    # see if we are at the top
    if new_path == bottom:
        return

    for x in walk_up(new_path):
        yield x

Here is a naive test via pytest

import pytest

@pytest.fixture(autouse=True)
def make_tmpdir(tmpdir):
    tmp_dir = tmpdir.mkdir("faka")
    return str(tmp_dir)


def test_walk_up(make_tmpdir):
    dirs = list(walk_up(make_tmpdir))
    assert isinstance(dirs[0][0], str)
    assert dirs[0][0].split("/")[-1] == "faka"
    assert dirs[0][1] == []
    assert dirs[0][2] == []

Thank you to @lambdamusic and @rednafi for keeping this example fresh and alive!

@zdavkeos this code is used in Pipfile FWIW, .... now what's your license?

https://github.com/pypa/pipenv/blob/master/pipenv/patched/pipfile/api.py#L27

FWIW, I created a library that was inspired by this snippet a long while ago: https://github.com/datafolklabs/backpedal ... it has little traction but my intent is to keep it alive, and well tested. Licensed as BSD-three-clause.

pip install backpedal