From 39dcdc99c081d1f5d128cebad0fdddbc84d6fefa Mon Sep 17 00:00:00 2001
From: barneygale <barney.gale@gmail.com>
Date: Wed, 24 May 2023 22:51:16 +0100
Subject: [PATCH] GH-104898: Add __slots__ to os.PathLike

---
 Lib/os.py                                                   | 2 ++
 Lib/pathlib.py                                              | 6 +-----
 Lib/test/test_os.py                                         | 6 ++++++
 .../Library/2023-05-24-22-50-21.gh-issue-104898.UbT2S4.rst  | 1 +
 4 files changed, 10 insertions(+), 5 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2023-05-24-22-50-21.gh-issue-104898.UbT2S4.rst

diff --git a/Lib/os.py b/Lib/os.py
index 598c9e502301f7..31b957f13215d5 100644
--- a/Lib/os.py
+++ b/Lib/os.py
@@ -1079,6 +1079,8 @@ class PathLike(abc.ABC):
 
     """Abstract base class for implementing the file system path protocol."""
 
+    __slots__ = ()
+
     @abc.abstractmethod
     def __fspath__(self):
         """Return the file system path representation of the object."""
diff --git a/Lib/pathlib.py b/Lib/pathlib.py
index 3a7a1241ba77f6..fb78939dcc31ba 100644
--- a/Lib/pathlib.py
+++ b/Lib/pathlib.py
@@ -233,7 +233,7 @@ def __repr__(self):
         return "<{}.parents>".format(type(self._path).__name__)
 
 
-class PurePath(object):
+class PurePath(os.PathLike):
     """Base class for manipulating paths without I/O.
 
     PurePath represents a filesystem path and offers operations which
@@ -707,10 +707,6 @@ def match(self, path_pattern, *, case_sensitive=None):
                 return False
         return True
 
-# Can't subclass os.PathLike from PurePath and keep the constructor
-# optimizations in PurePath.__slots__.
-os.PathLike.register(PurePath)
-
 
 class PurePosixPath(PurePath):
     """PurePath subclass for non-Windows systems.
diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index 584cc05ca82a55..c6810c07ae09d8 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -4640,6 +4640,12 @@ class A(os.PathLike):
     def test_pathlike_class_getitem(self):
         self.assertIsInstance(os.PathLike[bytes], types.GenericAlias)
 
+    def test_pathlike_subclass_slots(self):
+        class A(os.PathLike):
+            __slots__ = ()
+            def __fspath__(self):
+                return ''
+        self.assertFalse(hasattr(A(), '__dict__'))
 
 class TimesTests(unittest.TestCase):
     def test_times(self):
diff --git a/Misc/NEWS.d/next/Library/2023-05-24-22-50-21.gh-issue-104898.UbT2S4.rst b/Misc/NEWS.d/next/Library/2023-05-24-22-50-21.gh-issue-104898.UbT2S4.rst
new file mode 100644
index 00000000000000..e596ab36f5c729
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-05-24-22-50-21.gh-issue-104898.UbT2S4.rst
@@ -0,0 +1 @@
+Add missing :attr:`~object.__slots__` to :class:`os.PathLike`.