Merge pull request #356 from bgilbert/3.10

Remove conditionals for Python 3.10 features

Author: bgilbert

examples/deepzoom/deepzoom_multiserver.py

@@ -28,16 +28,12 @@
 import os
 from pathlib import Path, PurePath
 from threading import Lock
-from typing import TYPE_CHECKING, Any, Literal
+from typing import Any, Literal, TypeAlias
 import zlib
 
 from flask import Flask, Response, abort, make_response, render_template, url_for
 from PIL import Image, ImageCms
 
-if TYPE_CHECKING:
-    # Python 3.10+
-    from typing import TypeAlias
-
 if os.name == 'nt':
     _dll_path = os.getenv('OPENSLIDE_PATH')
     if _dll_path is not None:
@@ -68,17 +64,16 @@
 )
 SRGB_PROFILE = ImageCms.getOpenProfile(BytesIO(SRGB_PROFILE_BYTES))
 
-if TYPE_CHECKING:
-    ColorMode: TypeAlias = Literal[
-        'default',
-        'absolute-colorimetric',
-        'perceptual',
-        'relative-colorimetric',
-        'saturation',
-        'embed',
-        'ignore',
-    ]
-    Transform: TypeAlias = Callable[[Image.Image], None]
+ColorMode: TypeAlias = Literal[
+    'default',
+    'absolute-colorimetric',
+    'perceptual',
+    'relative-colorimetric',
+    'saturation',
+    'embed',
+    'ignore',
+]
+Transform: TypeAlias = Callable[[Image.Image], None]
 
 
 class DeepZoomMultiServer(Flask):

examples/deepzoom/deepzoom_server.py

@@ -27,17 +27,13 @@
 import os
 from pathlib import Path
 import re
-from typing import TYPE_CHECKING, Any, Literal
+from typing import Any, Literal, TypeAlias
 from unicodedata import normalize
 import zlib
 
 from flask import Flask, Response, abort, make_response, render_template, url_for
 from PIL import Image, ImageCms
 
-if TYPE_CHECKING:
-    # Python 3.10+
-    from typing import TypeAlias
-
 if os.name == 'nt':
     _dll_path = os.getenv('OPENSLIDE_PATH')
     if _dll_path is not None:
@@ -70,17 +66,16 @@
 )
 SRGB_PROFILE = ImageCms.getOpenProfile(BytesIO(SRGB_PROFILE_BYTES))
 
-if TYPE_CHECKING:
-    ColorMode: TypeAlias = Literal[
-        'default',
-        'absolute-colorimetric',
-        'perceptual',
-        'relative-colorimetric',
-        'saturation',
-        'embed',
-        'ignore',
-    ]
-    Transform: TypeAlias = Callable[[Image.Image], None]
+ColorMode: TypeAlias = Literal[
+    'default',
+    'absolute-colorimetric',
+    'perceptual',
+    'relative-colorimetric',
+    'saturation',
+    'embed',
+    'ignore',
+]
+Transform: TypeAlias = Callable[[Image.Image], None]
 
 
 class DeepZoomServer(Flask):

examples/deepzoom/deepzoom_tile.py

@@ -34,16 +34,12 @@
 import re
 import shutil
 import sys
-from typing import TYPE_CHECKING, Literal
+from typing import TYPE_CHECKING, Literal, TypeAlias
 from unicodedata import normalize
 import zlib
 
 from PIL import Image, ImageCms
 
-if TYPE_CHECKING:
-    # Python 3.10+
-    from typing import TypeAlias
-
 if os.name == 'nt':
     _dll_path = os.getenv('OPENSLIDE_PATH')
     if _dll_path is not None:
@@ -76,20 +72,21 @@
 )
 SRGB_PROFILE = ImageCms.getOpenProfile(BytesIO(SRGB_PROFILE_BYTES))
 
+ColorMode: TypeAlias = Literal[
+    'default',
+    'absolute-colorimetric',
+    'perceptual',
+    'relative-colorimetric',
+    'saturation',
+    'embed',
+    'ignore',
+]
+Transform: TypeAlias = Callable[[Image.Image], None]
 if TYPE_CHECKING:
-    ColorMode: TypeAlias = Literal[
-        'default',
-        'absolute-colorimetric',
-        'perceptual',
-        'relative-colorimetric',
-        'saturation',
-        'embed',
-        'ignore',
-    ]
+    # Python 3.12+
     TileQueue: TypeAlias = multiprocessing.queues.JoinableQueue[
         tuple[str | None, int, tuple[int, int], Path] | None
     ]
-    Transform: TypeAlias = Callable[[Image.Image], None]
 
 
 class TileWorker(Process):

openslide/deepzoom.py

@@ -26,17 +26,13 @@
 
 from io import BytesIO
 import math
-from typing import TYPE_CHECKING
+from typing import TypeGuard
 from xml.etree.ElementTree import Element, ElementTree, SubElement
 
 from PIL import Image
 
 import openslide
 
-if TYPE_CHECKING:
-    # Python 3.10+
-    from typing import TypeGuard
-
 
 class DeepZoomGenerator:
     """Generates Deep Zoom tiles and metadata."""

openslide/lowlevel.py

@@ -50,16 +50,13 @@
 from itertools import count
 import os
 import platform
-from typing import TYPE_CHECKING, Any, Protocol, TypeVar, cast
+from typing import TYPE_CHECKING, Any, ParamSpec, Protocol, TypeAlias, TypeVar, cast
 
 from PIL import Image
 
 from . import _convert
 
 if TYPE_CHECKING:
-    # Python 3.10+
-    from typing import ParamSpec, TypeAlias
-
     from _convert import _Buffer
 
 
@@ -199,9 +196,7 @@ def from_param(cls, obj: _OpenSlideCache) -> _OpenSlideCache:
         return obj
 
 
-if TYPE_CHECKING:
-    # Python 3.10+
-    Filename: TypeAlias = str | bytes | os.PathLike[Any]
+Filename: TypeAlias = str | bytes | os.PathLike[Any]
 
 
 class _filename_p:
@@ -314,24 +309,25 @@ def __call__(self, *_args: Any) -> Any:
         raise OpenSlideVersionError(self._minimum_version)
 
 
-# gate runtime code that requires ParamSpec, Python 3.10+
-if TYPE_CHECKING:
-    _P = ParamSpec('_P')
-    _T = TypeVar('_T', covariant=True)
+_P = ParamSpec('_P')
+_T = TypeVar('_T', covariant=True)
 
-    class _Func(Protocol[_P, _T]):
-        available: bool
 
-        def __call__(self, *args: _P.args) -> _T: ...  # type: ignore[valid-type]
+class _Func(Protocol[_P, _T]):
+    available: bool
 
-    class _CTypesFunc(_Func[_P, _T]):
-        restype: type | None
-        argtypes: list[type]
-        errcheck: _ErrCheck
+    def __call__(self, *args: _P.args) -> _T: ...  # type: ignore[valid-type]
 
-    _ErrCheck: TypeAlias = (
-        Callable[[Any, _CTypesFunc[..., Any], tuple[Any, ...]], Any] | None
-    )
+
+class _CTypesFunc(_Func[_P, _T]):
+    restype: type | None
+    argtypes: list[type]
+    errcheck: _ErrCheck
+
+
+_ErrCheck: TypeAlias = (
+    Callable[[Any, _CTypesFunc[..., Any], tuple[Any, ...]], Any] | None
+)
 
 
 # resolve and return an OpenSlide function with the specified properties
@@ -361,11 +357,7 @@ def _wraps_funcs(
     wrapped: list[_Func[..., Any]],
 ) -> Callable[[Callable[_P, _T]], _Func[_P, _T]]:
     def decorator(fn: Callable[_P, _T]) -> _Func[_P, _T]:
-        if TYPE_CHECKING:
-            # requires ParamSpec, Python 3.10+
-            f = cast(_Func[_P, _T], fn)
-        else:
-            f = fn
+        f = cast('_Func[_P, _T]', fn)
         f.available = True
         for w in wrapped:
             f.available = f.available and w.available