use tempfile.TemporaryDirectory to cleanup garbage- dir

Python has a very nice rm_rf hidden in
tempfile.TemporaryDirectory._rmtree we can use it to cleanup our
"garbage-" dir
https://github.com/python/cpython/blob/3d43f1dce3e9aaded38f9a2c73e3c66acf85505c/Lib/tempfile.py#L784-L812

Author: graingert

changelog/8940.bugfix.rst

@@ -0,0 +1 @@
+Fixed an issue where dirs without S_IXUSR prevented pytest from cleaning up the temp dir

src/_pytest/pathlib.py

@@ -6,7 +6,7 @@
 import os
 import shutil
 import sys
-import uuid
+import tempfile
 import warnings
 from enum import Enum
 from functools import partial
@@ -254,11 +254,10 @@ def maybe_delete_a_numbered_dir(path: Path) -> None:
     lock_path = None
     try:
         lock_path = create_cleanup_lock(path)
-        parent = path.parent
-
-        garbage = parent.joinpath(f"garbage-{uuid.uuid4()}")
-        path.rename(garbage)
-        rm_rf(garbage)
+        with tempfile.TemporaryDirectory(
+            prefix="garbage-", dir=path.parent
+        ) as garbage:
+            path.replace(garbage)
     except OSError:
         #  known races:
         #  * other process did a cleanup at the same time

testing/test_pathlib.py

@@ -351,6 +351,26 @@ def test_long_path_during_cleanup(tmp_path):
     assert not os.path.isdir(extended_path)
 
 
+def test_permission_denied_during_cleanup(tmp_path):
+    """
+    Ensure that deleting a numbered dir does not fail because of missing file
+    permission bits (#7940).
+    """
+    path = tmp_path / "temp-1"
+    p = path / "ham" / "spam" / "eggs"
+    p.parent.mkdir(parents=True)
+    p.touch(mode=0)
+    for p in p.parents:
+        if p == path:
+            break
+        p.chmod(mode=0)
+
+    lock_path = get_lock_path(path)
+    maybe_delete_a_numbered_dir(path)
+    assert not path.exists()
+    assert not lock_path.is_file()
+
+
 def test_get_extended_length_path_str():
     assert get_extended_length_path_str(r"c:\foo") == r"\\?\c:\foo"
     assert get_extended_length_path_str(r"\\share\foo") == r"\\?\UNC\share\foo"