Join two absolute paths?

Question

How do i join two absolute paths in Python?

e.g.

path1 = 'C:/folder1/folder2/'
path2 = 'D:/directory1/directory2/'

The desired result is: C:/folder1/folder2/directory1/directory2/

I tried os.path.join but it neglects the first path because it detects it's an absolute path. So what's the best way to join paths like this in Python?

Thank you!

Answer 1

Use the pathlib module to make the 2nd path relative and join it with the first one:

from pathlib import Path

path1 = Path('C:/folder1/folder2/')
path2 = Path('D:/directory1/directory2/')

path3 = path1 / path2.relative_to(path2.anchor)
# result: C:\folder1\folder2\directory1\directory2

---

To visualize what's happening, let's look at some intermediate output.

Path.anchor gives you the drive letter (or / on linux) of an absolute path. If the path is relative, it returns the empty string:

>>> path2.anchor
'D:\\'
>>> Path('foo').anchor
''

We can use this with Path.relative_to to turn path2 into a relative path. If it was already relative, it won't be affected by this operation:

>>> path2.relative_to(path2.anchor)
WindowsPath('directory1/directory2')
>>> Path('foo').relative_to('')
WindowsPath('foo')

Finally, now that we have a relative path, it can trivially be combined with path1 with the / operator.