From 9286dd8d7af99d03a8df8a1503b1534d8066d145 Mon Sep 17 00:00:00 2001
From: abmantis <amfcalt@gmail.com>
Date: Fri, 8 May 2026 17:47:23 +0100
Subject: [PATCH] Fix deprecated_class to work with inheritance

---
 homeassistant/helpers/deprecation.py | 35 +++++++++++++++++++++-------
 tests/helpers/test_deprecation.py    |  7 ++++++
 2 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/homeassistant/helpers/deprecation.py b/homeassistant/helpers/deprecation.py
index 8f4dfca21102cf..0be8dfeb2b1546 100644
--- a/homeassistant/helpers/deprecation.py
+++ b/homeassistant/helpers/deprecation.py
@@ -6,7 +6,7 @@
 import functools
 import inspect
 import logging
-from typing import Any, NamedTuple
+from typing import Any, NamedTuple, cast
 
 
 def deprecated_substitute[_ObjectT: object](
@@ -86,27 +86,44 @@ def get_deprecated(
     return config.get(new_name, default)
 
 
-def deprecated_class[**_P, _R](
+def deprecated_class[_T](
     replacement: str, *, breaks_in_ha_version: str | None = None
-) -> Callable[[Callable[_P, _R]], Callable[_P, _R]]:
+) -> Callable[[type[_T]], type[_T]]:
     """Mark class as deprecated and provide a replacement class to be used instead.
 
     If the deprecated function was called from a custom integration, ask the user to
     report an issue.
     """
 
-    def deprecated_decorator(cls: Callable[_P, _R]) -> Callable[_P, _R]:
+    def deprecated_decorator(cls: type[_T]) -> type[_T]:
         """Decorate class as deprecated."""
+        base_meta = type(cls)
 
-        @functools.wraps(cls)
-        def deprecated_cls(*args: _P.args, **kwargs: _P.kwargs) -> _R:
-            """Wrap for the original class."""
+        def __call__(self: type[Any], *args: Any, **kwargs: Any) -> Any:
             _print_deprecation_warning(
                 cls, replacement, "class", "instantiated", breaks_in_ha_version
             )
-            return cls(*args, **kwargs)
+            return base_meta.__call__(self, *args, **kwargs)
+
+        deprecated_meta = type(
+            f"Deprecated{base_meta.__name__}",
+            (base_meta,),
+            {"__call__": __call__},
+        )
+
+        deprecated_cls = deprecated_meta(
+            cls.__name__,
+            (cls,),
+            {
+                "__module__": cls.__module__,
+                "__qualname__": cls.__qualname__,
+                "__doc__": cls.__doc__,
+                "__slots__": (),
+                "__wrapped__": cls,
+            },
+        )
 
-        return deprecated_cls
+        return cast(type[_T], deprecated_cls)
 
     return deprecated_decorator
 
diff --git a/tests/helpers/test_deprecation.py b/tests/helpers/test_deprecation.py
index b77e7e1ef44f0a..825b688afbf203 100644
--- a/tests/helpers/test_deprecation.py
+++ b/tests/helpers/test_deprecation.py
@@ -121,6 +121,10 @@ class MockDeprecatedClass:
     """Mock class for deprecated testing."""
 
 
+class MockDeprecatedSubClass(MockDeprecatedClass):
+    """Mock subclass for deprecated testing."""
+
+
 @patch("logging.getLogger")
 def test_deprecated_class(mock_get_logger) -> None:
     """Test deprecated class."""
@@ -131,6 +135,9 @@ def test_deprecated_class(mock_get_logger) -> None:
     assert mock_logger.warning.called
     assert len(mock_logger.warning.mock_calls) == 1
 
+    MockDeprecatedSubClass()
+    assert len(mock_logger.warning.mock_calls) == 2
+
 
 @pytest.mark.parametrize(
     ("breaks_in_ha_version", "extra_msg"),