bpo-45192: Fix a bug that infers the type of an os.PathLike[bytes] object as str (GH-28323) (GH-29111)
An object implementing the os.PathLike protocol can represent a file
system path as a str or bytes object.
Therefore, _infer_return_type function should infer os.PathLike[str]
object as str type and os.PathLike[bytes] object as bytes type.
(cherry picked from commit 6270d3eeaf17b50abc4f8f4d97790d66179638e4)
Co-authored-by: Kyungmin Lee <rekyungmin@gmail.com>
diff --git a/Lib/tempfile.py b/Lib/tempfile.py
index efcf7a7..7b68212 100644
--- a/Lib/tempfile.py
+++ b/Lib/tempfile.py
@@ -88,6 +88,10 @@ def _infer_return_type(*args):
for arg in args:
if arg is None:
continue
+
+ if isinstance(arg, _os.PathLike):
+ arg = _os.fspath(arg)
+
if isinstance(arg, bytes):
if return_type is str:
raise TypeError("Can't mix bytes and non-bytes in "
diff --git a/Lib/test/test_tempfile.py b/Lib/test/test_tempfile.py
index 96946a2..2b0ec46 100644
--- a/Lib/test/test_tempfile.py
+++ b/Lib/test/test_tempfile.py
@@ -62,6 +62,25 @@ def test_infer_return_type_multiples_and_none(self):
def test_infer_return_type_pathlib(self):
self.assertIs(str, tempfile._infer_return_type(pathlib.Path('/')))
+ def test_infer_return_type_pathlike(self):
+ class Path:
+ def __init__(self, path):
+ self.path = path
+
+ def __fspath__(self):
+ return self.path
+
+ self.assertIs(str, tempfile._infer_return_type(Path('/')))
+ self.assertIs(bytes, tempfile._infer_return_type(Path(b'/')))
+ self.assertIs(str, tempfile._infer_return_type('', Path('')))
+ self.assertIs(bytes, tempfile._infer_return_type(b'', Path(b'')))
+ self.assertIs(bytes, tempfile._infer_return_type(None, Path(b'')))
+ self.assertIs(str, tempfile._infer_return_type(None, Path('')))
+
+ with self.assertRaises(TypeError):
+ tempfile._infer_return_type('', Path(b''))
+ with self.assertRaises(TypeError):
+ tempfile._infer_return_type(b'', Path(''))
# Common functionality.