From f81fdea2ac81299b95cc3668a3180ab6db7ba6d5 Mon Sep 17 00:00:00 2001
From: Dylan Baker <dylan@pnwbakers.com>
Date: Mon, 6 Jul 2026 19:03:40 +0000
Subject: [PATCH] _typing: mark ImmutableListProtocol method arguemnts as
 position only

PEP 570 (finalized in Python 3.8) added position only arguments to the
Python language. These are separated from position-or-keyword arguments
by adding `/` between them. I.e., `def func(pos_only: int, /, pos_or_kw:
str)`. Many Python builtins in 3.8 were either changed to position only,
or already were position only as this had always existed in the C API,
but not in Python.

Mypy does not complain about these without more strictness turned on,
but pylance does, by default, complain that a `list[str]` cannot be
assigned to `ImmutableListProtocol[str]` because of the position-only
mismatch.
---
 mesonbuild/_typing.py | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/mesonbuild/_typing.py b/mesonbuild/_typing.py
index 8336c46bd..2777d1983 100644
--- a/mesonbuild/_typing.py
+++ b/mesonbuild/_typing.py
@@ -43,27 +43,27 @@ class ImmutableListProtocol(Protocol[T]):
     def __iter__(self) -> typing.Iterator[T]: ...
 
     @typing.overload
-    def __getitem__(self, index: int) -> T: ...
+    def __getitem__(self, index: int, /) -> T: ...
     @typing.overload
-    def __getitem__(self, index: slice) -> typing.List[T]: ...
+    def __getitem__(self, index: slice, /) -> typing.List[T]: ...
 
-    def __contains__(self, item: T) -> bool: ...
+    def __contains__(self, item: T, /) -> bool: ...
 
     def __reversed__(self) -> typing.Iterator[T]: ...
 
     def __len__(self) -> int: ...
 
-    def __add__(self, other: typing.List[T]) -> typing.List[T]: ...
+    def __add__(self, other: typing.List[T], /) -> typing.List[T]: ...
 
-    def __eq__(self, other: typing.Any) -> bool: ...
-    def __ne__(self, other: typing.Any) -> bool: ...
-    def __le__(self, other: typing.Any) -> bool: ...
-    def __lt__(self, other: typing.Any) -> bool: ...
-    def __gt__(self, other: typing.Any) -> bool: ...
-    def __ge__(self, other: typing.Any) -> bool: ...
+    def __eq__(self, other: typing.Any, /) -> bool: ...
+    def __ne__(self, other: typing.Any, /) -> bool: ...
+    def __le__(self, other: typing.Any, /) -> bool: ...
+    def __lt__(self, other: typing.Any, /) -> bool: ...
+    def __gt__(self, other: typing.Any, /) -> bool: ...
+    def __ge__(self, other: typing.Any, /) -> bool: ...
 
-    def count(self, item: T) -> int: ...
+    def count(self, item: T, /) -> int: ...
 
-    def index(self, item: T) -> int: ...
+    def index(self, item: T, /) -> int: ...
 
     def copy(self) -> typing.List[T]: ...