Comparing two paths in python

Question

Consider:

path1 = "c:/fold1/fold2"
list_of_paths = ["c:\\fold1\\fold2","c:\\temp\\temp123"]

if path1 in list_of_paths:
    print "found"

I would like the if statement to return True, but it evaluates to False, since it is a string comparison.

How to compare two paths irrespective of the forward or backward slashes they have? I'd prefer not to use the replace function to convert both strings to a common format.

Answer 1

Use os.path.normpath to convert c:/fold1/fold2 to c:\fold1\fold2:

>>> path1 = "c:/fold1/fold2" >>> list_of_paths = ["c:\\fold1\\fold2","c:\\temp\\temp123"] >>> os.path.normpath(path1) 'c:\\fold1\\fold2' >>> os.path.normpath(path1) in list_of_paths True >>> os.path.normpath(path1) in (os.path.normpath(p) for p in list_of_paths) True 

• os.path.normpath(path1) in map(os.path.normpath, list_of_paths) also works, but it will build a list with entire path items even though there's match in the middle. (In Python 2.x)

On Windows, you must use os.path.normcase to compare paths because on Windows, paths are not case-sensitive.

Answer 2

All of these answers mention os.path.normpath, but none of them mention os.path.realpath:

os.path.realpath(path)

Return the canonical path of the specified filename, eliminating any symbolic links encountered in the path (if they are supported by the operating system).

New in version 2.2.

So then:

if os.path.realpath(path1) in (os.path.realpath(p) for p in list_of_paths):     # ... 

Answer 3

The os.path module contains several functions to normalize file paths so that equivalent paths normalize to the same string. You may want normpath, normcase, abspath, samefile, or some other tool.

Answer 4

If you are using python-3, you can use pathlib to achieve your goal:

import pathlib
path1 = pathlib.Path("c:/fold1/fold2")
list_of_paths = [pathlib.Path(path) for path in ["c:\\fold1\\fold2","c:\\temp\\temp123"]]
assert path1 in list_of_paths