DEP: Ensure typing_extension is dependency for earlier python versions (#290)

* DEP: Ensure typing_extension is dependency for earlier python versions

* RF: Guard type definition to explicit type checking, add typing_extensions to [dev] extra

* fix linting

---------

Co-authored-by: Andreas Poehlmann <[email protected]>

Author: mgxd

pyproject.toml

@@ -61,6 +61,7 @@ dev = [
     "pydantic",
     "pydantic-settings",
     "smbprotocol",
+    "typing_extensions; python_version<'3.11'",
 ]
 
 [project.urls]

upath/core.py

@@ -19,11 +19,6 @@
 from typing import overload
 from urllib.parse import urlsplit
 
-if sys.version_info >= (3, 11):
-    from typing import Self
-else:
-    from typing_extensions import Self
-
 from fsspec.registry import get_filesystem_class
 from fsspec.spec import AbstractFileSystem
 
@@ -43,6 +38,11 @@
 if TYPE_CHECKING:
     from urllib.parse import SplitResult
 
+    if sys.version_info >= (3, 11):
+        from typing import Self
+    else:
+        from typing_extensions import Self
+
 __all__ = ["UPath"]
 
 

upath/implementations/sftp.py

@@ -1,13 +1,15 @@
 from __future__ import annotations
 
 import sys
+from typing import TYPE_CHECKING
 from typing import Any
 from typing import Generator
 
-if sys.version_info >= (3, 11):
-    from typing import Self
-else:
-    from typing_extensions import Self
+if TYPE_CHECKING:
+    if sys.version_info >= (3, 11):
+        from typing import Self
+    else:
+        from typing_extensions import Self
 
 from upath import UPath
 

upath/implementations/smb.py

@@ -3,12 +3,14 @@
 import os
 import sys
 import warnings
+from typing import TYPE_CHECKING
 from typing import Any
 
-if sys.version_info >= (3, 11):
-    from typing import Self
-else:
-    from typing_extensions import Self
+if TYPE_CHECKING:
+    if sys.version_info >= (3, 11):
+        from typing import Self
+    else:
+        from typing_extensions import Self
 
 import smbprotocol.exceptions