diff options
| -rw-r--r-- | Lib/os.py | 6 | ||||
| -rw-r--r-- | Lib/test/test_os.py | 8 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2019-11-22-12-08-52.bpo-38878.EJ0cFf.rst | 2 |
3 files changed, 15 insertions, 1 deletions
@@ -26,6 +26,8 @@ import abc import sys import stat as st +from _collections_abc import _check_methods + _names = sys.builtin_module_names # Note: more names are added to __all__ later. @@ -1070,7 +1072,9 @@ class PathLike(abc.ABC): @classmethod def __subclasshook__(cls, subclass): - return hasattr(subclass, '__fspath__') + if cls is PathLike: + return _check_methods(subclass, '__fspath__') + return NotImplemented def __class_getitem__(cls, type): return cls diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py index f44ddba..82c441c 100644 --- a/Lib/test/test_os.py +++ b/Lib/test/test_os.py @@ -4048,6 +4048,14 @@ class TestPEP519(unittest.TestCase): self.assertRaises(ZeroDivisionError, self.fspath, FakePath(ZeroDivisionError())) + def test_pathlike_subclasshook(self): + # bpo-38878: subclasshook causes subclass checks + # true on abstract implementation. + class A(os.PathLike): + pass + self.assertFalse(issubclass(FakePath, A)) + self.assertTrue(issubclass(FakePath, os.PathLike)) + def test_pathlike_class_getitem(self): self.assertIs(os.PathLike[bytes], os.PathLike) diff --git a/Misc/NEWS.d/next/Library/2019-11-22-12-08-52.bpo-38878.EJ0cFf.rst b/Misc/NEWS.d/next/Library/2019-11-22-12-08-52.bpo-38878.EJ0cFf.rst new file mode 100644 index 0000000..9cbdf08 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2019-11-22-12-08-52.bpo-38878.EJ0cFf.rst @@ -0,0 +1,2 @@ +Fixed __subclasshook__ of :class:`os.PathLike` to return a correct result +upon inheritence. Patch by Bar Harel. |