From 80e645c63a298d7e5ec15d2698ba28ff9315a796 Mon Sep 17 00:00:00 2001
From: HasanGenis <hasan_genis28@outlook.com>
Date: Wed, 23 Sep 2026 14:11:45 +0300
Subject: [PATCH 1/2] feat(sorts): make recursive quick sort generic over
 comparable items

Add a Comparable Protocol + TypeVar bound to recursive_quick_sort's quick_sort() so it is typed list[T] instead of a bare list, matching the pattern in insertion_sort.py. Adds a doctest asserting TypeError on non-comparable mixed-type input and registers it (aliased to recursive_quick_sort to avoid colliding with sorts.quick_sort.quick_sort) in the shared test battery and in test_sort_rejects_non_comparable_items.

Part of #15234
---
 sorts/recursive_quick_sort.py | 17 ++++++++++++++++-
 tests/test_sorts.py           |  3 +++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/sorts/recursive_quick_sort.py b/sorts/recursive_quick_sort.py
index c29009aca673..62808e288f52 100644
--- a/sorts/recursive_quick_sort.py
+++ b/sorts/recursive_quick_sort.py
@@ -1,10 +1,25 @@
-def quick_sort(data: list) -> list:
+from typing import Any, Protocol, TypeVar
+
+
+class Comparable(Protocol):
+    def __lt__(self, other: Any, /) -> bool: ...
+
+
+T = TypeVar("T", bound=Comparable)
+
+
+def quick_sort[T: Comparable](data: list[T]) -> list[T]:
     """
     >>> for data in ([2, 1, 0], [2.2, 1.1, 0], "quick_sort"):
     ...     quick_sort(data) == sorted(data)
     True
     True
     True
+
+    >>> quick_sort([1, "a"])
+    Traceback (most recent call last):
+        ...
+    TypeError: '<=' not supported between instances of 'str' and 'int'
     """
     if len(data) <= 1:
         return data
diff --git a/tests/test_sorts.py b/tests/test_sorts.py
index d18be1c22b83..44d6a49a95f3 100644
--- a/tests/test_sorts.py
+++ b/tests/test_sorts.py
@@ -43,6 +43,7 @@
 from sorts.quick_sort import quick_sort
 from sorts.recursive_insertion_sort import rec_insertion_sort
 from sorts.recursive_mergesort_array import merge
+from sorts.recursive_quick_sort import quick_sort as recursive_quick_sort
 from sorts.reversort import reversort
 from sorts.selection_sort import selection_sort
 from sorts.shell_sort import shell_sort
@@ -79,6 +80,7 @@ def test_heap_sort() -> None:
     pancake_sort,
     patience_sort,
     quick_sort,
+    recursive_quick_sort,
     reversort,
     selection_sort,
     shell_sort,
@@ -149,6 +151,7 @@ def test_rec_insertion_sort(case) -> None:
         odd_even_sort,
         odd_even_transposition,
         pancake_sort,
+        recursive_quick_sort,
         reversort,
         selection_sort,
         shrink_shell_sort,

From 792887f515490b8c557f4fc73c2264b5f420338a Mon Sep 17 00:00:00 2001
From: Christian Clauss <cclauss@me.com>
Date: Thu, 24 Sep 2026 16:39:16 +0200
Subject: [PATCH 2/2] Apply suggestion from @cclauss

---
 sorts/recursive_quick_sort.py | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/sorts/recursive_quick_sort.py b/sorts/recursive_quick_sort.py
index 62808e288f52..d71e79fd6450 100644
--- a/sorts/recursive_quick_sort.py
+++ b/sorts/recursive_quick_sort.py
@@ -1,13 +1,10 @@
-from typing import Any, Protocol, TypeVar
+from typing import Any, Protocol
 
 
 class Comparable(Protocol):
     def __lt__(self, other: Any, /) -> bool: ...
 
 
-T = TypeVar("T", bound=Comparable)
-
-
 def quick_sort[T: Comparable](data: list[T]) -> list[T]:
     """
     >>> for data in ([2, 1, 0], [2.2, 1.1, 0], "quick_sort"):