From 50bf3fa45a0ba502d054dd61aebceed626871f16 Mon Sep 17 00:00:00 2001
From: GiGaGon <107241144+MeGaGiGaGon@users.noreply.github.com>
Date: Thu, 19 Jun 2025 14:51:23 -0700
Subject: [PATCH] [`flake8-pie`] Add fix safety section to `PIE794` (#18802)

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## Summary

<!-- What's the purpose of the change? What does it do, and why? -->

Part of #15584

This PR adds a fix safety section to `PIE794`

I could not track down when this rule was initially implemented/made
unsafe due how old it could be + multiple large refactors to `ruff`.

There is no comment/reasoning in the code given for the unsafety.

Here is a code example demonstrating why it should be unsafe, since
removing any of the assignments would change program behavior
[playground](https://play.ruff.rs/01004644-4259-4449-a581-5007cd59846a)
```py
class A:
    x = 1
    x = 2
    print(x)

class B:
    x = print(3)
    x = print(4)

class C:
    x = [1,2,3]
    y = x
    x = y[1]
```

## Test Plan

<!-- How was it tested? -->

N/A, no tests affected.

---------

Co-authored-by: Dylan <dylwil3@gmail.com>
---
 .../flake8_pie/rules/duplicate_class_field_definition.rs      | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/crates/ruff_linter/src/rules/flake8_pie/rules/duplicate_class_field_definition.rs b/crates/ruff_linter/src/rules/flake8_pie/rules/duplicate_class_field_definition.rs
index a430f8c9b0..003cf23b13 100644
--- a/crates/ruff_linter/src/rules/flake8_pie/rules/duplicate_class_field_definition.rs
+++ b/crates/ruff_linter/src/rules/flake8_pie/rules/duplicate_class_field_definition.rs
@@ -30,6 +30,10 @@ use crate::{AlwaysFixableViolation, Fix};
 ///     name = Tom
 ///     ...
 /// ```
+///
+/// ## Fix Safety
+/// This fix is always marked as unsafe since we cannot know
+//  for certain which assignment was intended.
 #[derive(ViolationMetadata)]
 pub(crate) struct DuplicateClassFieldDefinition {
     name: String,