From 092551352958c3d7b4b10e00669a161033dd2662 Mon Sep 17 00:00:00 2001
From: Steve C <diceroll123@gmail.com>
Date: Sat, 2 Nov 2024 13:10:56 -0400
Subject: [PATCH] [`pyupgrade`] - ignore kwarg unpacking for `UP044` (#14053)

## Summary

Fixes #14047

## Test Plan

`catgo test`

---------

Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>
---
 .../test/fixtures/pyupgrade/UP044.py          |  8 +++++++
 .../pyupgrade/rules/use_pep646_unpack.rs      | 22 ++++++++++++++++---
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP044.py b/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP044.py
index cd5aebe3780d1..7468a2635bba3 100644
--- a/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP044.py
+++ b/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP044.py
@@ -17,3 +17,11 @@ def f(*args: Unpack[other.Type]): pass
 def foo(*args: Unpack[int | str]) -> None: pass
 def foo(*args: Unpack[int and str]) -> None: pass
 def foo(*args: Unpack[int > str]) -> None: pass
+
+# We do not use the shorthand unpacking syntax in the following cases
+from typing import TypedDict
+class KwargsDict(TypedDict):
+    x: int
+    y: int
+
+def foo(name: str, /, **kwargs: Unpack[KwargsDict]) -> None: pass
diff --git a/crates/ruff_linter/src/rules/pyupgrade/rules/use_pep646_unpack.rs b/crates/ruff_linter/src/rules/pyupgrade/rules/use_pep646_unpack.rs
index 454b7b0c8b4e1..4ac19e34715cc 100644
--- a/crates/ruff_linter/src/rules/pyupgrade/rules/use_pep646_unpack.rs
+++ b/crates/ruff_linter/src/rules/pyupgrade/rules/use_pep646_unpack.rs
@@ -11,7 +11,7 @@ use crate::{checkers::ast::Checker, settings::types::PythonVersion};
 /// ## Why is this bad?
 /// [PEP 646] introduced a new syntax for unpacking sequences based on the `*`
 /// operator. This syntax is more concise and readable than the previous
-/// `typing.Unpack` syntax.
+/// `Unpack[]` syntax.
 ///
 /// ## Example
 ///
@@ -30,8 +30,7 @@ use crate::{checkers::ast::Checker, settings::types::PythonVersion};
 ///     pass
 /// ```
 ///
-/// ## References
-/// - [PEP 646](https://peps.python.org/pep-0646/#unpack-for-backwards-compatibility)
+/// [PEP 646]: https://peps.python.org/pep-0646/
 #[violation]
 pub struct NonPEP646Unpack;
 
@@ -58,6 +57,23 @@ pub(crate) fn use_pep646_unpack(checker: &mut Checker, expr: &ExprSubscript) {
         return;
     }
 
+    // Ignore `kwarg` unpacking, as in:
+    // ```python
+    // def f(**kwargs: Unpack[Array]):
+    //     ...
+    // ```
+    if checker
+        .semantic()
+        .current_statement()
+        .as_function_def_stmt()
+        .and_then(|stmt| stmt.parameters.kwarg.as_ref())
+        .and_then(|kwarg| kwarg.annotation.as_ref())
+        .and_then(|annotation| annotation.as_subscript_expr())
+        .is_some_and(|subscript| subscript == expr)
+    {
+        return;
+    }
+
     let ExprSubscript {
         range,
         value,