From 91995aa5169175de55494bc3bb59781c7a3097fc Mon Sep 17 00:00:00 2001
From: Dan Parizher <105245560+danparizher@users.noreply.github.com>
Date: Thu, 18 Sep 2025 10:05:05 -0400
Subject: [PATCH] [`pyupgrade`] Fix false positive when class name is shadowed
 by local variable (`UP008`) (#20427)

## Summary

Fixes #20422

---------

Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
---
 .../resources/test/fixtures/pyupgrade/UP008.py   | 16 ++++++++++++++++
 .../rules/super_call_with_parameters.rs          |  6 +++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP008.py b/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP008.py
index be5b629cab..dd46c6c4d0 100644
--- a/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP008.py
+++ b/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP008.py
@@ -271,3 +271,19 @@ class ChildI9(ParentI):
                 if False: super
                 if False: __class__
         builtins.super(ChildI9, self).f()
+
+
+# See: https://github.com/astral-sh/ruff/issues/20422
+# UP008 should not apply when the class variable is shadowed
+class A:
+    def f(self):
+        return 1
+
+class B(A):
+    def f(self):
+        return 2
+
+class C(B):
+    def f(self):
+        C = B  # Local variable C shadows the class name
+        return super(C, self).f()  # Should NOT trigger UP008
diff --git a/crates/ruff_linter/src/rules/pyupgrade/rules/super_call_with_parameters.rs b/crates/ruff_linter/src/rules/pyupgrade/rules/super_call_with_parameters.rs
index c6dd7f2811..30ff93d6be 100644
--- a/crates/ruff_linter/src/rules/pyupgrade/rules/super_call_with_parameters.rs
+++ b/crates/ruff_linter/src/rules/pyupgrade/rules/super_call_with_parameters.rs
@@ -139,7 +139,11 @@ pub(crate) fn super_call_with_parameters(checker: &Checker, call: &ast::ExprCall
         return;
     };
 
-    if !((first_arg_id == "__class__" || first_arg_id == parent_name.as_str())
+    if !((first_arg_id == "__class__"
+        || (first_arg_id == parent_name.as_str()
+            // If the first argument matches the class name, check if it's a local variable
+            // that shadows the class name. If so, don't apply UP008.
+            && !checker.semantic().current_scope().has(first_arg_id)))
         && second_arg_id == parent_arg.name().as_str())
     {
         return;