Move test compatibility modules into a compat package.

Author: jaraco

importlib_resources/tests/compat/__init__.py

@@ -1,10 +1,14 @@
+"""
+Backward-compatability shims to support Python 3.9 and earlier.
+"""
+
 import os
 
 
 try:
     from test.support import import_helper  # type: ignore
 except ImportError:
-    # Python 3.9 and earlier
+
     class import_helper:  # type: ignore
         from test.support import (
             modules_setup,
@@ -17,13 +21,12 @@ class import_helper:  # type: ignore
 try:
     from test.support import os_helper  # type: ignore
 except ImportError:
-    # Python 3.9 compat
+
     class os_helper:  # type:ignore
         from test.support import temp_dir
 
 
 try:
-    # Python 3.10
     from test.support.os_helper import unlink
 except ImportError:
     from test.support import unlink as _unlink

importlib_resources/tests/_compat.py renamed to importlib_resources/tests/compat/py39.py

@@ -6,7 +6,7 @@
 from .. import abc
 from ..abc import TraversableResources, ResourceReader
 from . import util
-from ._compat import os_helper
+from .compat.py39 import os_helper
 
 
 class SimpleLoader:

importlib_resources/tests/test_custom.py

@@ -9,7 +9,7 @@
 from . import data01
 from . import util
 from . import _path
-from ._compat import os_helper, import_helper
+from .compat.py39 import os_helper, import_helper
 
 
 @contextlib.contextmanager

importlib_resources/tests/test_files.py

@@ -8,7 +8,7 @@
 
 from . import data01
 from ..abc import ResourceReader
-from ._compat import import_helper, os_helper
+from .compat.py39 import import_helper, os_helper
 from . import zip as zip_