fix importing typing under if TYPE_CHECKING: (enthought#448)

(cherry picked from commit ba1b18f)

comtypes/__init__.py

@@ -3,7 +3,7 @@
 
 import atexit
 from ctypes import *
-from ctypes import _SimpleCData
+from ctypes import _Pointer, _SimpleCData
 
 try:
     from _ctypes import COMError
@@ -22,6 +22,36 @@
 import sys
 import types
 
+# fmt: off
+from typing import (
+    Any, ClassVar, overload, TYPE_CHECKING, TypeVar,
+    # instead of `builtins`. see PEP585
+    Dict, List, Tuple, Type,
+    # instead of `collections.abc`. see PEP585
+    Callable, Iterable, Iterator,
+    # instead of `A | B` and `None | A`. see PEP604
+    Optional, Union as _UnionT,  # avoiding confusion with `ctypes.Union`
+)
+# fmt: on
+if TYPE_CHECKING:
+    from ctypes import _CData  # only in `typeshed`, private in runtime
+    from comtypes import hints as hints  # type: ignore
+else:
+    _CData = _SimpleCData.__mro__[:-1][-1]
+
+from comtypes.GUID import GUID
+from comtypes import patcher
+from comtypes._npsupport import interop as npsupport
+from comtypes._memberspec import (
+    ComMemberGenerator,
+    _ComMemberSpec,
+    DispMemberGenerator,
+    _DispMemberSpec,
+    _encode_idl,
+    _resolve_argspec,
+)
+
+
 ################################################################
 
 # fmt: off
@@ -63,59 +93,6 @@ def wrapper(cls):
     return wrapper
 # fmt: on
 
-################################################################
-
-# type hinting symbols
-#
-# `if TYPE_CHECKING:` code block must not be executed because `TYPE_CHECKING`
-# is always `False` in runtime.
-# see https://peps.python.org/pep-0484/#runtime-or-type-checking
-#
-if sys.version_info >= (3, 5):
-    from typing import TYPE_CHECKING
-else:  # typehints in this package don't support Py<3.5 due to importing symbols.
-    TYPE_CHECKING = False
-#
-# Annotations must be placed in a `# type:` comment in according to PEP484.
-# see https://peps.python.org/pep-0484/#suggested-syntax-for-python-2-7-and-straddling-code
-# - `NameError` never raises by using those symbols.
-# - It is not able to use any runtime introspections, such as
-#   `typing.get_type_hints` or `typing.get_origin`.
-#
-if TYPE_CHECKING:
-    from ctypes import _CData  # only in `typeshed`, private in runtime
-
-    # _CData = _SimpleCData.__mro__[:-1][-1]  # defining in runtime
-    from ctypes import _Pointer
-    from typing import Any, ClassVar, overload, TypeVar
-
-    # XXX: symbols for backward compatibility.
-    # instead of `builtins`. see PEP585.
-    from typing import Dict, List, Tuple, Type
-
-    # instead of `collections.abc`. see PEP585.
-    from typing import Callable, Iterable, Iterator
-
-    # instead of `A | B` and `None | A`. see PEP604.
-    from typing import Union as _UnionT  #  avoiding confusion with `ctypes.Union`
-    from typing import Optional
-
-    # utilities or workarounds for annotations.
-    from comtypes import hints as hints
-
-################################################################
-
-from comtypes.GUID import GUID
-from comtypes import patcher
-from comtypes._npsupport import interop as npsupport
-from comtypes._memberspec import (
-    ComMemberGenerator,
-    _ComMemberSpec,
-    DispMemberGenerator,
-    _DispMemberSpec,
-    _encode_idl,
-    _resolve_argspec,
-)
 
 ################################################################
 if sys.version_info >= (3, 0):
@@ -849,8 +826,9 @@ def COMMETHOD(idlflags, restype, methodname, *argspec):
 ################################################################
 # IUnknown, the root of all evil...
 
+_T_IUnknown = TypeVar("_T_IUnknown", bound="IUnknown")
+
 if TYPE_CHECKING:
-    _T_IUnknown = TypeVar("_T_IUnknown", bound="IUnknown")
 
     class _IUnknown_Base(c_void_p):
         """This is workaround to avoid false-positive of static type checking.

comtypes/_memberspec.py

@@ -1,28 +1,26 @@
 import ctypes
-
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    Iterator,
+    List,
+    Optional,
+    Tuple,
+    Type,
+    Union as _UnionT,
+)
+
+from comtypes import _CData
 import comtypes
-from comtypes import TYPE_CHECKING
-
-if TYPE_CHECKING:
-    from comtypes import _CData
-    from typing import (
-        Any,
-        Callable,
-        Dict,
-        Iterator,
-        List,
-        Optional,
-        Tuple,
-        Type,
-        Union as _UnionT,
-    )
-
-    PositionalParamFlagType = Tuple[int, Optional[str]]
-    OptionalParamFlagType = Tuple[int, Optional[str], Any]
-    ParamFlagType = _UnionT[PositionalParamFlagType, OptionalParamFlagType]
-    PositionalArgSpecElmType = Tuple[List[str], Type[_CData], str]
-    OptionalArgSpecElmType = Tuple[List[str], Type[_CData], str, Any]
-    ArgSpecElmType = _UnionT[PositionalArgSpecElmType, OptionalArgSpecElmType]
+
+
+PositionalParamFlagType = Tuple[int, Optional[str]]
+OptionalParamFlagType = Tuple[int, Optional[str], Any]
+ParamFlagType = _UnionT[PositionalParamFlagType, OptionalParamFlagType]
+PositionalArgSpecElmType = Tuple[List[str], Type[_CData], str]
+OptionalArgSpecElmType = Tuple[List[str], Type[_CData], str, Any]
+ArgSpecElmType = _UnionT[PositionalArgSpecElmType, OptionalArgSpecElmType]
 
 
 _PARAMFLAGS = {

comtypes/automation.py

@@ -3,24 +3,29 @@
 import datetime
 import decimal
 import sys
-
 from ctypes import *
 from ctypes import _Pointer
 from _ctypes import CopyComPointer
-from comtypes import (
-    BSTR,
-    COMError,
-    COMMETHOD,
-    GUID,
-    IID,
-    IUnknown,
-    STDMETHOD,
+from ctypes.wintypes import DWORD, LONG, UINT, VARIANT_BOOL, WCHAR, WORD
+from typing import (
+    Any,
+    Callable,
+    ClassVar,
+    List,
+    Optional,
     TYPE_CHECKING,
+    Tuple,
+    Union as _UnionT,
 )
+
+from comtypes import BSTR, COMError, COMMETHOD, GUID, IID, IUnknown, STDMETHOD
 from comtypes.hresult import *
 import comtypes.patcher
 import comtypes
 
+if TYPE_CHECKING:
+    from comtypes import hints  # type: ignore
+
 try:
     from comtypes import _safearray
 except (ImportError, AttributeError):
@@ -29,21 +34,6 @@ class _safearray(object):
         tagSAFEARRAY = None
 
 
-from ctypes.wintypes import DWORD, LONG, UINT, VARIANT_BOOL, WCHAR, WORD
-
-if TYPE_CHECKING:
-    from typing import (
-        Any,
-        Callable,
-        ClassVar,
-        List,
-        Optional,
-        Tuple,
-        Union as _UnionT,
-    )
-    from comtypes import hints
-
-
 if sys.version_info >= (3, 0):
     int_types = (int,)
     str_types = (str,)

comtypes/client/__init__.py

@@ -12,28 +12,35 @@
 import logging
 import os
 import sys
+from typing import (
+    Any,
+    Optional,
+    overload,
+    Type,
+    TYPE_CHECKING,
+    TypeVar,
+    Union as _UnionT,
+)
 
 import comtypes
 from comtypes.hresult import *
-from comtypes import automation, CoClass, GUID, IUnknown, TYPE_CHECKING, typeinfo
+from comtypes import automation, CoClass, GUID, IUnknown, typeinfo
 import comtypes.client.dynamic
 from comtypes.client._constants import Constants
 from comtypes.client._events import GetEvents, ShowEvents, PumpEvents
 from comtypes.client._generate import GetModule
 from comtypes.client._code_cache import _find_gen_dir
 
+if TYPE_CHECKING:
+    from comtypes import hints  # type: ignore
+
 gen_dir = _find_gen_dir()
 import comtypes.gen
 
 ### for testing
 ##gen_dir = None
 
-if TYPE_CHECKING:
-    from typing import Any, Optional, overload, Type, TypeVar, Union as _UnionT
-    from comtypes import hints
-
-    _T_IUnknown = TypeVar("_T_IUnknown", bound=IUnknown)
-
+_T_IUnknown = TypeVar("_T_IUnknown", bound=IUnknown)
 logger = logging.getLogger(__name__)
 
 

comtypes/client/_generate.py

@@ -5,6 +5,7 @@
 import os
 import sys
 import types
+from typing import Any, Tuple, List, Optional, Dict, Union as _UnionT
 
 if sys.version_info >= (3, 0):
     base_text_type = str
@@ -13,13 +14,10 @@
     base_text_type = basestring
     import _winreg as winreg
 
-from comtypes import GUID, TYPE_CHECKING, typeinfo
+from comtypes import GUID, typeinfo
 import comtypes.client
 from comtypes.tools import codegenerator, tlbparser
 
-if TYPE_CHECKING:
-    from typing import Any, Tuple, List, Optional, Dict, Union as _UnionT
-
 
 logger = logging.getLogger(__name__)
 

comtypes/tools/codegenerator.py

@@ -7,27 +7,17 @@
 import os
 import sys
 import textwrap
+from typing import Any, Dict, Iterator, List, Optional, Tuple, Union as _UnionT
 
 if sys.version_info >= (3, 0):
     import io
 else:
     import cStringIO as io
 
 import comtypes
-from comtypes import TYPE_CHECKING, typeinfo
+from comtypes import typeinfo
 from comtypes.tools import tlbparser, typedesc
 
-if TYPE_CHECKING:
-    from typing import (
-        Any,
-        Dict,
-        Iterator,
-        List,
-        Optional,
-        Tuple,
-        Union as _UnionT,
-    )
-
 
 version = comtypes.__version__
 

comtypes/tools/tlbparser.py

@@ -1,26 +1,24 @@
 from __future__ import print_function
 import os
 import sys
-from ctypes import alignment, c_void_p, sizeof, windll
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    List,
+    Optional,
+    Type,
+    TYPE_CHECKING,
+    TypeVar,
+    Tuple,
+    Union as _UnionT,
+)
+from ctypes import alignment, c_void_p, _Pointer, sizeof, windll
 
-from comtypes import automation, COMError, TYPE_CHECKING, typeinfo
+from comtypes import automation, _CData, COMError, typeinfo
 from comtypes.tools import typedesc
 from comtypes.client._code_cache import _get_module_filename
 
-if TYPE_CHECKING:
-    from typing import (
-        Any,
-        Callable,
-        Dict,
-        List,
-        Optional,
-        Type,
-        TypeVar,
-        Tuple,
-        Union as _UnionT,
-    )
-    from ctypes import _CData, _Pointer
-
 
 # Is the process 64-bit?
 is_64bits = sys.maxsize > 2**32

comtypes/tools/typedesc.py

@@ -2,13 +2,11 @@
 # in typedesc_base
 
 import ctypes
-from comtypes import TYPE_CHECKING
+from typing import Any, List, Optional, Tuple, Union as _UnionT
+
 from comtypes.typeinfo import ITypeLib, TLIBATTR
 from comtypes.tools.typedesc_base import *
 
-if TYPE_CHECKING:
-    from typing import Any, List, Optional, Tuple, Union as _UnionT
-
 
 class TypeLib(object):
     def __init__(self, name, guid, major, minor, doc=None):