From 8dcd3b5afddcccae967acf176235472bf9fbb153 Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Mon, 16 Feb 2026 17:28:00 +0000
Subject: [PATCH] Optimization: make State final and avoid construction via
 cls()

Constructions via cls() was pretty slow due to the large number of keyword
arguments, as this used a generic calling convention.
---
 mypy/build.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/mypy/build.py b/mypy/build.py
index bf56075427d0..97c8b9d5ef90 100644
--- a/mypy/build.py
+++ b/mypy/build.py
@@ -39,6 +39,7 @@
     TypeAlias as _TypeAlias,
     TypedDict,
     cast,
+    final,
 )
 
 from librt.base64 import b64encode
@@ -2172,6 +2173,7 @@ def __init__(self, reason: int = SuppressionReason.NOT_FOUND) -> None:
         self.reason = reason
 
 
+@final
 class State:
     """The state for a module.
 
@@ -2258,9 +2260,8 @@ class State:
     # Mapping from line number to type ignore codes on this line (for imports only).
     imports_ignored: dict[int, list[str]]
 
-    @classmethod
+    @staticmethod
     def new_state(
-        cls,
         id: str | None,
         path: str | None,
         source: str | None,
@@ -2350,7 +2351,7 @@ def new_state(
             error_lines = []
             imports_ignored = {}
 
-        state = cls(
+        state = State(
             manager=manager,
             order=State.order_counter,
             id=id,