[cpython/Lib/tempfile.py] `mkdtemp` - canonicalise directory name

[SamuelMarks]

Feature or enhancement

Proposal:

I just solved an annoying bug where my temporary directory worked on Windows and Linux but not macOS; because mkdtemp doesn't canonicalise its output; causing "/private/" to be prefixed to some of my paths but not the first path out of with TemporaryDirectory() as directory.

I found where the one line solution can be applied:
https://github.com/python/cpython/blob/3.12/Lib/tempfile.py#L395

diff --git a/Lib/tempfile.py b/Lib/tempfile.py
index cbfc172a789b25..2ded1af58b73dd 100644
--- a/Lib/tempfile.py
+++ b/Lib/tempfile.py
@@ -392,7 +392,7 @@ def mkdtemp(suffix=None, prefix=None, dir=None):
                 continue
             else:
                 raise
-        return _os.path.abspath(file)
+        return _os.path.realpath(_os.path.abspath(file))
 
     raise FileExistsError(_errno.EEXIST,
                           "No usable temporary directory name found")

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

This was discussed on the Node.js project nodejs/node#11422

Linked PRs

• gh-114545: [Lib/tempfile.py] mkdtemp - canonicalise directory name #114691

[Ravencentric]

I encountered this a while back

# MacOS
>>> from tempfile import TemporaryDirectory
>>> from pathlib import Path
>>> TemporaryDirectory().name
'/var/folders/kj/5xf97h1x0t741q334hgxxf_r0000gn/T/tmpcqfpeiwq'
>>> Path(TemporaryDirectory().name).resolve()
PosixPath('/private/var/folders/kj/5xf97h1x0t741q334hgxxf_r0000gn/T/tmp0sfpzcnh')

Was also brought up in this discussion https://discuss.python.org/t/tempfile-temporarydirectory-name-should-return-pathlib-path-instead-of-str/40900/10

[aisk]

Hi, I think this (with additional tests) deserves a PR, and PRs are welcome in Python.