Remove code that is impossible to reach on python 3.9+

Author: Pierre-Sassoulas

src/_pytest/config/argparsing.py

@@ -4,9 +4,7 @@
 import argparse
 from collections.abc import Mapping
 from collections.abc import Sequence
-from gettext import gettext
 import os
-import sys
 from typing import Any
 from typing import Callable
 from typing import cast
@@ -446,44 +444,6 @@ def parse_args(  # type: ignore
             getattr(parsed, FILE_OR_DIR).extend(unrecognized)
         return parsed
 
-    if sys.version_info < (3, 9):  # pragma: no cover
-        # Backport of https://github.com/python/cpython/pull/14316 so we can
-        # disable long --argument abbreviations without breaking short flags.
-        def _parse_optional(
-            self, arg_string: str
-        ) -> tuple[argparse.Action | None, str, str | None] | None:
-            if not arg_string:
-                return None
-            if arg_string[0] not in self.prefix_chars:
-                return None
-            if arg_string in self._option_string_actions:
-                action = self._option_string_actions[arg_string]
-                return action, arg_string, None
-            if len(arg_string) == 1:
-                return None
-            if "=" in arg_string:
-                option_string, explicit_arg = arg_string.split("=", 1)
-                if option_string in self._option_string_actions:
-                    action = self._option_string_actions[option_string]
-                    return action, option_string, explicit_arg
-            if self.allow_abbrev or not arg_string.startswith("--"):
-                option_tuples = self._get_option_tuples(arg_string)
-                if len(option_tuples) > 1:
-                    msg = gettext(
-                        "ambiguous option: %(option)s could match %(matches)s"
-                    )
-                    options = ", ".join(option for _, option, _ in option_tuples)
-                    self.error(msg % {"option": arg_string, "matches": options})
-                elif len(option_tuples) == 1:
-                    (option_tuple,) = option_tuples
-                    return option_tuple
-            if self._negative_number_matcher.match(arg_string):
-                if not self._has_negative_number_optionals:
-                    return None
-            if " " in arg_string:
-                return None
-            return None, arg_string, None
-
 
 class DropShorterLongHelpFormatter(argparse.HelpFormatter):
     """Shorten help for long options that differ only in extra hyphens.

testing/test_assertrewrite.py

@@ -1018,10 +1018,6 @@ def test_zipfile(self, pytester: Pytester) -> None:
         )
         assert pytester.runpytest().ret == ExitCode.NO_TESTS_COLLECTED
 
-    @pytest.mark.skipif(
-        sys.version_info < (3, 9),
-        reason="importlib.resources.files was introduced in 3.9",
-    )
     def test_load_resource_via_files_with_rewrite(self, pytester: Pytester) -> None:
         example = pytester.path.joinpath("demo") / "example"
         init = pytester.path.joinpath("demo") / "__init__.py"