From 9f4bb0f19d37ac0649a6d6a99784fdf242bd5d65 Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Tue, 28 Oct 2025 08:07:14 +0200
Subject: [PATCH 01/13] config: inline `_initini`

It doesn't help understanding much and doesn't deal with only ini
(config). So inline it into `_preparse`.
---
 src/_pytest/config/__init__.py | 59 +++++++++++++++++-----------------
 1 file changed, 29 insertions(+), 30 deletions(-)

diff --git a/src/_pytest/config/__init__.py b/src/_pytest/config/__init__.py
index 3cad7a7d5eb..92a8fae9193 100644
--- a/src/_pytest/config/__init__.py
+++ b/src/_pytest/config/__init__.py
@@ -1246,35 +1246,6 @@ def pytest_load_initial_conftests(self, early_config: Config) -> None:
             ),
         )
 
-    def _initini(self, args: Sequence[str]) -> None:
-        ns, unknown_args = self._parser.parse_known_and_unknown_args(
-            args, namespace=copy.copy(self.option)
-        )
-        rootpath, inipath, inicfg, ignored_config_files = determine_setup(
-            inifile=ns.inifilename,
-            override_ini=ns.override_ini,
-            args=ns.file_or_dir + unknown_args,
-            rootdir_cmd_arg=ns.rootdir or None,
-            invocation_dir=self.invocation_params.dir,
-        )
-        self._rootpath = rootpath
-        self._inipath = inipath
-        self._ignored_config_files = ignored_config_files
-        self.inicfg = inicfg
-        self._parser.extra_info["rootdir"] = str(self.rootpath)
-        self._parser.extra_info["inifile"] = str(self.inipath)
-        self._parser.addini("addopts", "Extra command line options", "args")
-        self._parser.addini("minversion", "Minimally required pytest version")
-        self._parser.addini(
-            "pythonpath", type="paths", help="Add paths to sys.path", default=[]
-        )
-        self._parser.addini(
-            "required_plugins",
-            "Plugins that must be present for pytest to run",
-            type="args",
-            default=[],
-        )
-
     def _consider_importhook(self, args: Sequence[str]) -> None:
         """Install the PEP 302 import hook if using assertion rewriting.
 
@@ -1399,7 +1370,35 @@ def _preparse(self, args: list[str], addopts: bool = True) -> None:
                     self._validate_args(shlex.split(env_addopts), "via PYTEST_ADDOPTS")
                     + args
                 )
-        self._initini(args)
+
+        ns, unknown_args = self._parser.parse_known_and_unknown_args(
+            args, namespace=copy.copy(self.option)
+        )
+        rootpath, inipath, inicfg, ignored_config_files = determine_setup(
+            inifile=ns.inifilename,
+            override_ini=ns.override_ini,
+            args=ns.file_or_dir + unknown_args,
+            rootdir_cmd_arg=ns.rootdir or None,
+            invocation_dir=self.invocation_params.dir,
+        )
+        self._rootpath = rootpath
+        self._inipath = inipath
+        self._ignored_config_files = ignored_config_files
+        self.inicfg = inicfg
+        self._parser.extra_info["rootdir"] = str(self.rootpath)
+        self._parser.extra_info["inifile"] = str(self.inipath)
+        self._parser.addini("addopts", "Extra command line options", "args")
+        self._parser.addini("minversion", "Minimally required pytest version")
+        self._parser.addini(
+            "pythonpath", type="paths", help="Add paths to sys.path", default=[]
+        )
+        self._parser.addini(
+            "required_plugins",
+            "Plugins that must be present for pytest to run",
+            type="args",
+            default=[],
+        )
+
         if addopts:
             args[:] = (
                 self._validate_args(self.getini("addopts"), "via addopts config") + args

From a32a0120ffb88057735574475acea95d1d8789b7 Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Tue, 28 Oct 2025 08:19:22 +0200
Subject: [PATCH 02/13] config: better typing for `get_config` and
 `Config.fromdictargs`

---
 src/_pytest/config/__init__.py | 21 ++++++++++-----------
 testing/test_config.py         |  2 +-
 2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/src/_pytest/config/__init__.py b/src/_pytest/config/__init__.py
index 92a8fae9193..1e91b60788e 100644
--- a/src/_pytest/config/__init__.py
+++ b/src/_pytest/config/__init__.py
@@ -10,6 +10,7 @@
 from collections.abc import Generator
 from collections.abc import Iterable
 from collections.abc import Iterator
+from collections.abc import Mapping
 from collections.abc import Sequence
 import contextlib
 import copy
@@ -290,23 +291,21 @@ def directory_arg(path: str, optname: str) -> str:
 
 
 def get_config(
-    args: list[str] | None = None,
+    args: Iterable[str] | None = None,
     plugins: Sequence[str | _PluggyPlugin] | None = None,
 ) -> Config:
     # Subsequent calls to main will create a fresh instance.
     pluginmanager = PytestPluginManager()
-    config = Config(
-        pluginmanager,
-        invocation_params=Config.InvocationParams(
-            args=args or (),
-            plugins=plugins,
-            dir=pathlib.Path.cwd(),
-        ),
+    invocation_params = Config.InvocationParams(
+        args=args or (),
+        plugins=plugins,
+        dir=pathlib.Path.cwd(),
     )
+    config = Config(pluginmanager, invocation_params=invocation_params)
 
-    if args is not None:
+    if invocation_params.args:
         # Handle any "-p no:plugin" args.
-        pluginmanager.consider_preparse(args, exclude_only=True)
+        pluginmanager.consider_preparse(invocation_params.args, exclude_only=True)
 
     for spec in default_plugins:
         pluginmanager.import_plugin(spec)
@@ -1202,7 +1201,7 @@ def cwd_relative_nodeid(self, nodeid: str) -> str:
         return nodeid
 
     @classmethod
-    def fromdictargs(cls, option_dict, args) -> Config:
+    def fromdictargs(cls, option_dict: Mapping[str, Any], args: list[str]) -> Config:
         """Constructor usable for subprocesses."""
         config = get_config(args)
         config.option.__dict__.update(option_dict)
diff --git a/testing/test_config.py b/testing/test_config.py
index 9df00d7a219..9cbb50ab2ed 100644
--- a/testing/test_config.py
+++ b/testing/test_config.py
@@ -1425,7 +1425,7 @@ def test_inifilename(self, tmp_path: Path) -> None:
         )
         with MonkeyPatch.context() as mp:
             mp.chdir(cwd)
-            config = Config.fromdictargs(option_dict, ())
+            config = Config.fromdictargs(option_dict, [])
             inipath = absolutepath(inifilename)
 
         assert config.args == [str(cwd)]

From 349bfd9661e91e191608aa0558990e4442b84b34 Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Tue, 28 Oct 2025 08:39:35 +0200
Subject: [PATCH 03/13] config: make it clear only `parse_setoption` can raise
 `PrintHelp`

---
 src/_pytest/config/__init__.py | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/_pytest/config/__init__.py b/src/_pytest/config/__init__.py
index 1e91b60788e..5857d7f536c 100644
--- a/src/_pytest/config/__init__.py
+++ b/src/_pytest/config/__init__.py
@@ -1541,16 +1541,16 @@ def parse(self, args: list[str], addopts: bool = True) -> None:
             args = self._parser.parse_setoption(
                 args, self.option, namespace=self.option
             )
-            self.args, self.args_source = self._decide_args(
-                args=args,
-                pyargs=self.known_args_namespace.pyargs,
-                testpaths=self.getini("testpaths"),
-                invocation_dir=self.invocation_params.dir,
-                rootpath=self.rootpath,
-                warn=True,
-            )
         except PrintHelp:
-            pass
+            return
+        self.args, self.args_source = self._decide_args(
+            args=args,
+            pyargs=self.known_args_namespace.pyargs,
+            testpaths=self.getini("testpaths"),
+            invocation_dir=self.invocation_params.dir,
+            rootpath=self.rootpath,
+            warn=True,
+        )
 
     def issue_config_time_warning(self, warning: Warning, stacklevel: int) -> None:
         """Issue and handle a warning during the "configure" stage.

From ab2859b1b01202c8cec1f468363e72ff18dfe2ec Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Tue, 28 Oct 2025 09:00:32 +0200
Subject: [PATCH 04/13] helpconfig: improve typing in `HelpAction`

---
 src/_pytest/helpconfig.py | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/_pytest/helpconfig.py b/src/_pytest/helpconfig.py
index 760f8269dd1..8a4e5beba91 100644
--- a/src/_pytest/helpconfig.py
+++ b/src/_pytest/helpconfig.py
@@ -3,20 +3,23 @@
 
 from __future__ import annotations
 
-from argparse import Action
+import argparse
 from collections.abc import Generator
+from collections.abc import Sequence
 import os
 import sys
+from typing import Any
 
 from _pytest.config import Config
 from _pytest.config import ExitCode
 from _pytest.config import PrintHelp
+from _pytest.config.argparsing import MyOptionParser
 from _pytest.config.argparsing import Parser
 from _pytest.terminal import TerminalReporter
 import pytest
 
 
-class HelpAction(Action):
+class HelpAction(argparse.Action):
     """An argparse Action that will raise an exception in order to skip the
     rest of the argument parsing when --help is passed.
 
@@ -26,20 +29,29 @@ class HelpAction(Action):
     implemented by raising SystemExit.
     """
 
-    def __init__(self, option_strings, dest=None, default=False, help=None):
+    def __init__(
+        self, option_strings: Sequence[str], dest: str, *, help: str | None = None
+    ) -> None:
         super().__init__(
             option_strings=option_strings,
             dest=dest,
-            const=True,
-            default=default,
             nargs=0,
+            const=True,
+            default=False,
             help=help,
         )
 
-    def __call__(self, parser, namespace, values, option_string=None):
+    def __call__(
+        self,
+        parser: argparse.ArgumentParser,
+        namespace: argparse.Namespace,
+        values: str | Sequence[Any] | None,
+        option_string: str | None = None,
+    ) -> None:
         setattr(namespace, self.dest, self.const)
 
         # We should only skip the rest of the parsing after preparse is done.
+        assert isinstance(parser, MyOptionParser)
         if getattr(parser._parser, "after_preparse", False):
             raise PrintHelp
 

From b7e9612df013f5e694f8e9f8361b886fc8f18c68 Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Tue, 28 Oct 2025 09:24:01 +0200
Subject: [PATCH 05/13] config: make `_config_source_hint` type safe

Set to `None` instead of using `hasattr`.
---
 src/_pytest/config/__init__.py   | 4 ++--
 src/_pytest/config/argparsing.py | 3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/_pytest/config/__init__.py b/src/_pytest/config/__init__.py
index 5857d7f536c..6e94328c1ba 100644
--- a/src/_pytest/config/__init__.py
+++ b/src/_pytest/config/__init__.py
@@ -1306,13 +1306,13 @@ def _unconfigure_python_path(self) -> None:
 
     def _validate_args(self, args: list[str], via: str) -> list[str]:
         """Validate known args."""
-        self._parser._config_source_hint = via  # type: ignore
+        self._parser._config_source_hint = via
         try:
             self._parser.parse_known_and_unknown_args(
                 args, namespace=copy.copy(self.option)
             )
         finally:
-            del self._parser._config_source_hint  # type: ignore
+            self._parser._config_source_hint = None
 
         return args
 
diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index 99835884848..d53769eb042 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -54,6 +54,7 @@ def __init__(
         # Maps alias -> canonical name.
         self._ini_aliases: dict[str, str] = {}
         self.extra_info: dict[str, Any] = {}
+        self._config_source_hint: str | None = None
 
     def processoption(self, option: Argument) -> None:
         if self._processopt:
@@ -460,7 +461,7 @@ def error(self, message: str) -> NoReturn:
         """Transform argparse error message into UsageError."""
         msg = f"{self.prog}: error: {message}"
 
-        if hasattr(self._parser, "_config_source_hint"):
+        if self._parser._config_source_hint is not None:
             msg = f"{msg} ({self._parser._config_source_hint})"
 
         raise UsageError(self.format_usage() + msg)

From 95e0cf22fa1f9fa01a372216572f97a8e614205c Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Tue, 28 Oct 2025 09:32:58 +0200
Subject: [PATCH 06/13] config: rename `MyOptionParser` ->
 `PytestArgumentParser`

Initially wanted to rename it to `MyArgumentParser` to make it clearer
it's an `argparse.ArgumentParser`. But "My" looks funny, so change to
`Pytest` similar to `PytestPluginManager`.
---
 src/_pytest/config/argparsing.py | 6 +++---
 src/_pytest/helpconfig.py        | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index d53769eb042..99a530a54db 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -115,10 +115,10 @@ def parse(
         strargs = [os.fspath(x) for x in args]
         return self.optparser.parse_args(strargs, namespace=namespace)
 
-    def _getparser(self) -> MyOptionParser:
+    def _getparser(self) -> PytestArgumentParser:
         from _pytest._argcomplete import filescompleter
 
-        optparser = MyOptionParser(self, self.extra_info, prog=self.prog)
+        optparser = PytestArgumentParser(self, self.extra_info, prog=self.prog)
         groups = [*self._groups, self._anonymous]
         for group in groups:
             if group.options:
@@ -437,7 +437,7 @@ def _addoption_instance(self, option: Argument, shortupper: bool = False) -> Non
         self.options.append(option)
 
 
-class MyOptionParser(argparse.ArgumentParser):
+class PytestArgumentParser(argparse.ArgumentParser):
     def __init__(
         self,
         parser: Parser,
diff --git a/src/_pytest/helpconfig.py b/src/_pytest/helpconfig.py
index 8a4e5beba91..151164d62f9 100644
--- a/src/_pytest/helpconfig.py
+++ b/src/_pytest/helpconfig.py
@@ -13,8 +13,8 @@
 from _pytest.config import Config
 from _pytest.config import ExitCode
 from _pytest.config import PrintHelp
-from _pytest.config.argparsing import MyOptionParser
 from _pytest.config.argparsing import Parser
+from _pytest.config.argparsing import PytestArgumentParser
 from _pytest.terminal import TerminalReporter
 import pytest
 
@@ -51,7 +51,7 @@ def __call__(
         setattr(namespace, self.dest, self.const)
 
         # We should only skip the rest of the parsing after preparse is done.
-        assert isinstance(parser, MyOptionParser)
+        assert isinstance(parser, PytestArgumentParser)
         if getattr(parser._parser, "after_preparse", False):
             raise PrintHelp
 

From 4f07180276575856ebe3d35d02c8b415316ba56d Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Wed, 29 Oct 2025 10:28:29 +0200
Subject: [PATCH 07/13] config: inline `parse_setoption`

It only makes the code harder to understand in my opinion.

Also remove the manual `setattr(option, name, value)` which are unneeded
because `parse` already updates the `Namespace`.
---
 src/_pytest/config/__init__.py   |  7 +++----
 src/_pytest/config/argparsing.py | 12 ------------
 testing/test_parseopt.py         |  9 +++------
 3 files changed, 6 insertions(+), 22 deletions(-)

diff --git a/src/_pytest/config/__init__.py b/src/_pytest/config/__init__.py
index 6e94328c1ba..43a4cc3dfaf 100644
--- a/src/_pytest/config/__init__.py
+++ b/src/_pytest/config/__init__.py
@@ -56,6 +56,7 @@
 from _pytest._io import TerminalWriter
 from _pytest.compat import assert_never
 from _pytest.config.argparsing import Argument
+from _pytest.config.argparsing import FILE_OR_DIR
 from _pytest.config.argparsing import Parser
 import _pytest.deprecated
 import _pytest.hookspec
@@ -1538,13 +1539,11 @@ def parse(self, args: list[str], addopts: bool = True) -> None:
         self._preparse(args, addopts=addopts)
         self._parser.after_preparse = True  # type: ignore
         try:
-            args = self._parser.parse_setoption(
-                args, self.option, namespace=self.option
-            )
+            parsed = self._parser.parse(args, namespace=self.option)
         except PrintHelp:
             return
         self.args, self.args_source = self._decide_args(
-            args=args,
+            args=getattr(parsed, FILE_OR_DIR),
             pyargs=self.known_args_namespace.pyargs,
             testpaths=self.getini("testpaths"),
             invocation_dir=self.invocation_params.dir,
diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index 99a530a54db..eab942997c9 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -7,7 +7,6 @@
 from collections.abc import Sequence
 import os
 from typing import Any
-from typing import cast
 from typing import final
 from typing import Literal
 from typing import NoReturn
@@ -134,17 +133,6 @@ def _getparser(self) -> PytestArgumentParser:
         file_or_dir_arg.completer = filescompleter  # type: ignore
         return optparser
 
-    def parse_setoption(
-        self,
-        args: Sequence[str | os.PathLike[str]],
-        option: argparse.Namespace,
-        namespace: argparse.Namespace | None = None,
-    ) -> list[str]:
-        parsedoption = self.parse(args, namespace=namespace)
-        for name, value in parsedoption.__dict__.items():
-            setattr(option, name, value)
-        return cast(list[str], getattr(parsedoption, FILE_OR_DIR))
-
     def parse_known_args(
         self,
         args: Sequence[str | os.PathLike[str]],
diff --git a/testing/test_parseopt.py b/testing/test_parseopt.py
index 36db7b13989..d3c39d55820 100644
--- a/testing/test_parseopt.py
+++ b/testing/test_parseopt.py
@@ -158,19 +158,16 @@ def test_parse_will_set_default(self, parser: parseopt.Parser) -> None:
         parser.addoption("--hello", dest="hello", default="x", action="store")
         option = parser.parse([])
         assert option.hello == "x"
-        del option.hello
-        parser.parse_setoption([], option)
-        assert option.hello == "x"
 
-    def test_parse_setoption(self, parser: parseopt.Parser) -> None:
+    def test_parse_set_options(self, parser: parseopt.Parser) -> None:
         parser.addoption("--hello", dest="hello", action="store")
         parser.addoption("--world", dest="world", default=42)
 
         option = argparse.Namespace()
-        args = parser.parse_setoption(["--hello", "world"], option)
+        parser.parse(["--hello", "world"], option)
         assert option.hello == "world"
         assert option.world == 42
-        assert not args
+        assert getattr(option, parseopt.FILE_OR_DIR) == []
 
     def test_parse_special_destination(self, parser: parseopt.Parser) -> None:
         parser.addoption("--ultimate-answer", type=int)

From f56f7c5af9c1409f379c8445792b7b9522c01f39 Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Wed, 29 Oct 2025 11:18:19 +0200
Subject: [PATCH 08/13] config: tiny style improvement

---
 src/_pytest/config/argparsing.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index eab942997c9..26b226bd0b1 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -320,9 +320,7 @@ def names(self) -> list[str]:
 
     def attrs(self) -> Mapping[str, Any]:
         # Update any attributes set by processopt.
-        attrs = "default dest help".split()
-        attrs.append(self.dest)
-        for attr in attrs:
+        for attr in ("default", "dest", "help", self.dest):
             try:
                 self._attrs[attr] = getattr(self, attr)
             except AttributeError:

From e86d689cb935bcb61604f3397a98b8a23592a08d Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Wed, 29 Oct 2025 11:46:31 +0200
Subject: [PATCH 09/13] config: small code improvement

---
 src/_pytest/config/argparsing.py | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index 26b226bd0b1..ae0bc80e74e 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -460,16 +460,13 @@ def parse_args(  # type: ignore
     ) -> argparse.Namespace:
         """Allow splitting of positional arguments."""
         parsed, unrecognized = self.parse_known_args(args, namespace)
-        if unrecognized:
-            for arg in unrecognized:
-                if arg and arg[0] == "-":
-                    lines = [
-                        "unrecognized arguments: {}".format(" ".join(unrecognized))
-                    ]
-                    for k, v in sorted(self.extra_info.items()):
-                        lines.append(f"  {k}: {v}")
-                    self.error("\n".join(lines))
-            getattr(parsed, FILE_OR_DIR).extend(unrecognized)
+        for arg in unrecognized:
+            if arg.startswith("-"):
+                lines = ["unrecognized arguments: " + " ".join(unrecognized)]
+                for k, v in sorted(self.extra_info.items()):
+                    lines.append(f"  {k}: {v}")
+                self.error("\n".join(lines))
+        getattr(parsed, FILE_OR_DIR).extend(unrecognized)
         return parsed
 
 

From 6ff0670622061035b05d0a328cea6d795f48f3dd Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Wed, 29 Oct 2025 12:19:16 +0200
Subject: [PATCH 10/13] config: move `extra_info` handling from `parse_args` to
 `error`

This way it works for any error, which seems like better separation of
concerns.
---
 src/_pytest/config/argparsing.py | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index ae0bc80e74e..43d0118bd05 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -446,10 +446,12 @@ def __init__(
     def error(self, message: str) -> NoReturn:
         """Transform argparse error message into UsageError."""
         msg = f"{self.prog}: error: {message}"
-
         if self._parser._config_source_hint is not None:
             msg = f"{msg} ({self._parser._config_source_hint})"
-
+        if self.extra_info:
+            msg += "\n" + "\n".join(
+                f"  {k}: {v}" for k, v in sorted(self.extra_info.items())
+            )
         raise UsageError(self.format_usage() + msg)
 
     # Type ignored because typeshed has a very complex type in the superclass.
@@ -462,10 +464,7 @@ def parse_args(  # type: ignore
         parsed, unrecognized = self.parse_known_args(args, namespace)
         for arg in unrecognized:
             if arg.startswith("-"):
-                lines = ["unrecognized arguments: " + " ".join(unrecognized)]
-                for k, v in sorted(self.extra_info.items()):
-                    lines.append(f"  {k}: {v}")
-                self.error("\n".join(lines))
+                self.error("unrecognized arguments: " + " ".join(unrecognized))
         getattr(parsed, FILE_OR_DIR).extend(unrecognized)
         return parsed
 

From 8c6e01d6907465ca6c8101fe852f933b71bd0683 Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Wed, 29 Oct 2025 12:23:33 +0200
Subject: [PATCH 11/13] config: remove `_config_source_hint`, use `extra_info`
 instead

Let's use a single mechanism. The error is now shown in its own line but
that's fine.
---
 src/_pytest/config/__init__.py   | 4 ++--
 src/_pytest/config/argparsing.py | 3 ---
 testing/test_config.py           | 8 +++++---
 3 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/src/_pytest/config/__init__.py b/src/_pytest/config/__init__.py
index 43a4cc3dfaf..36fe4171582 100644
--- a/src/_pytest/config/__init__.py
+++ b/src/_pytest/config/__init__.py
@@ -1307,13 +1307,13 @@ def _unconfigure_python_path(self) -> None:
 
     def _validate_args(self, args: list[str], via: str) -> list[str]:
         """Validate known args."""
-        self._parser._config_source_hint = via
+        self._parser.extra_info["config source"] = via
         try:
             self._parser.parse_known_and_unknown_args(
                 args, namespace=copy.copy(self.option)
             )
         finally:
-            self._parser._config_source_hint = None
+            self._parser.extra_info.pop("config source", None)
 
         return args
 
diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index 43d0118bd05..8e50be753b3 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -53,7 +53,6 @@ def __init__(
         # Maps alias -> canonical name.
         self._ini_aliases: dict[str, str] = {}
         self.extra_info: dict[str, Any] = {}
-        self._config_source_hint: str | None = None
 
     def processoption(self, option: Argument) -> None:
         if self._processopt:
@@ -446,8 +445,6 @@ def __init__(
     def error(self, message: str) -> NoReturn:
         """Transform argparse error message into UsageError."""
         msg = f"{self.prog}: error: {message}"
-        if self._parser._config_source_hint is not None:
-            msg = f"{msg} ({self._parser._config_source_hint})"
         if self.extra_info:
             msg += "\n" + "\n".join(
                 f"  {k}: {v}" for k, v in sorted(self.extra_info.items())
diff --git a/testing/test_config.py b/testing/test_config.py
index 9cbb50ab2ed..f1221cea9d0 100644
--- a/testing/test_config.py
+++ b/testing/test_config.py
@@ -2290,9 +2290,10 @@ def test_addopts_from_env_not_concatenated(
         with pytest.raises(UsageError) as excinfo:
             config._preparse(["cache_dir=ignored"], addopts=True)
         assert (
-            "error: argument -o/--override-ini: expected one argument (via PYTEST_ADDOPTS)"
+            "error: argument -o/--override-ini: expected one argument"
             in excinfo.value.args[0]
         )
+        assert "via PYTEST_ADDOPTS" in excinfo.value.args[0]
 
     def test_addopts_from_ini_not_concatenated(self, pytester: Pytester) -> None:
         """`addopts` from configuration should not take values from normal args (#4265)."""
@@ -2303,10 +2304,11 @@ def test_addopts_from_ini_not_concatenated(self, pytester: Pytester) -> None:
         """
         )
         result = pytester.runpytest("cache_dir=ignored")
+        config = pytester._request.config
         result.stderr.fnmatch_lines(
             [
-                f"{pytester._request.config._parser.optparser.prog}: error: "
-                f"argument -o/--override-ini: expected one argument (via addopts config)"
+                f"{config._parser.optparser.prog}: error: argument -o/--override-ini: expected one argument",
+                "  config source: via addopts config",
             ]
         )
         assert result.ret == _pytest.config.ExitCode.USAGE_ERROR

From fc2d649280a335fb23d58bbd08a2e2b5f5bee50f Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Wed, 29 Oct 2025 12:56:09 +0200
Subject: [PATCH 12/13] config: use argparse intermixed args parsing instead of
 doing it ourselves

See https://docs.python.org/3/library/argparse.html#intermixed-parsing.
pytest uses the intermixed style, but implemented it manually, probably
because it as only added to argparse in Python 3.7.
---
 src/_pytest/config/argparsing.py | 16 +---------------
 1 file changed, 1 insertion(+), 15 deletions(-)

diff --git a/src/_pytest/config/argparsing.py b/src/_pytest/config/argparsing.py
index 8e50be753b3..fd907409c3f 100644
--- a/src/_pytest/config/argparsing.py
+++ b/src/_pytest/config/argparsing.py
@@ -111,7 +111,7 @@ def parse(
         self.optparser = self._getparser()
         try_argcomplete(self.optparser)
         strargs = [os.fspath(x) for x in args]
-        return self.optparser.parse_args(strargs, namespace=namespace)
+        return self.optparser.parse_intermixed_args(strargs, namespace=namespace)
 
     def _getparser(self) -> PytestArgumentParser:
         from _pytest._argcomplete import filescompleter
@@ -451,20 +451,6 @@ def error(self, message: str) -> NoReturn:
             )
         raise UsageError(self.format_usage() + msg)
 
-    # Type ignored because typeshed has a very complex type in the superclass.
-    def parse_args(  # type: ignore
-        self,
-        args: Sequence[str] | None = None,
-        namespace: argparse.Namespace | None = None,
-    ) -> argparse.Namespace:
-        """Allow splitting of positional arguments."""
-        parsed, unrecognized = self.parse_known_args(args, namespace)
-        for arg in unrecognized:
-            if arg.startswith("-"):
-                self.error("unrecognized arguments: " + " ".join(unrecognized))
-        getattr(parsed, FILE_OR_DIR).extend(unrecognized)
-        return parsed
-
 
 class DropShorterLongHelpFormatter(argparse.HelpFormatter):
     """Shorten help for long options that differ only in extra hyphens.

From 0c275c45958a817669149c3c4124c6474077ca1d Mon Sep 17 00:00:00 2001
From: Ran Benita <ran@unusedvar.com>
Date: Wed, 29 Oct 2025 18:16:11 +0200
Subject: [PATCH 13/13] helpconfig: remove unused `conftest_options` global

---
 src/_pytest/helpconfig.py | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/_pytest/helpconfig.py b/src/_pytest/helpconfig.py
index 151164d62f9..932e35ceacc 100644
--- a/src/_pytest/helpconfig.py
+++ b/src/_pytest/helpconfig.py
@@ -257,9 +257,6 @@ def showhelp(config: Config) -> None:
         tw.line("warning : " + warningreport.message, red=True)
 
 
-conftest_options = [("pytest_plugins", "list of plugin names to load")]
-
-
 def getpluginversioninfo(config: Config) -> list[str]:
     lines = []
     plugininfo = config.pluginmanager.list_plugin_distinfo()