From cc5c569a67b4ef8fb4fcedfcd7c73e8c01179b32 Mon Sep 17 00:00:00 2001
From: epenet <6771947+epenet@users.noreply.github.com>
Date: Wed, 2 Jul 2025 07:34:59 +0000
Subject: [PATCH] One more

---
 homeassistant/helpers/service_info/dhcp.py |  6 -----
 tests/conftest.py                          | 28 ++++++++++++----------
 tests/helpers/test_service_info.py         | 15 +++++++++---
 3 files changed, 28 insertions(+), 21 deletions(-)

diff --git a/homeassistant/helpers/service_info/dhcp.py b/homeassistant/helpers/service_info/dhcp.py
index eb9fe629123..d46c7a59004 100644
--- a/homeassistant/helpers/service_info/dhcp.py
+++ b/homeassistant/helpers/service_info/dhcp.py
@@ -18,9 +18,3 @@ class DhcpServiceInfo(BaseServiceInfo):
     as a lowercase string without colons.
     eg. "AA:BB:CC:12:34:56" is stored as "aabbcc123456"
     """
-
-    def __post_init__(self) -> None:
-        """Post init checks.
-
-        Needed so it can be overridden in tests.
-        """
diff --git a/tests/conftest.py b/tests/conftest.py
index 4fc3996bc7c..15f9243312c 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -156,18 +156,6 @@ asyncio.set_event_loop_policy(runner.HassEventLoopPolicy(False))
 asyncio.set_event_loop_policy = lambda policy: None
 
 
-def _dhcp_service_info_post_init(self: DhcpServiceInfo) -> None:
-    """Post-init processing for DhcpServiceInfo.
-
-    Ensure that the macaddress is always in lowercase and without colons to match DHCP service.
-    """
-    if self.macaddress != self.macaddress.lower().replace(":", ""):
-        raise ValueError("macaddress is not correctly formatted")
-
-
-DhcpServiceInfo.__post_init__ = _dhcp_service_info_post_init
-
-
 def pytest_addoption(parser: pytest.Parser) -> None:
     """Register custom pytest options."""
     parser.addoption("--dburl", action="store", default="sqlite://")
@@ -2091,3 +2079,19 @@ def disable_block_async_io() -> Generator[None]:
             blocking_call.object, blocking_call.function, blocking_call.original_func
         )
     calls.clear()
+
+
+_real_dhcp_service_info_init = DhcpServiceInfo.__init__
+
+
+def _dhcp_service_info_init(self: DhcpServiceInfo, *args: Any, **kwargs: Any) -> None:
+    """Override __init__ for DhcpServiceInfo.
+
+    Ensure that the macaddress is always in lowercase and without colons to match DHCP service.
+    """
+    _real_dhcp_service_info_init(self, *args, **kwargs)
+    if self.macaddress != self.macaddress.lower().replace(":", ""):
+        raise ValueError("macaddress is not correctly formatted")
+
+
+DhcpServiceInfo.__init__ = _dhcp_service_info_init
diff --git a/tests/helpers/test_service_info.py b/tests/helpers/test_service_info.py
index c84be7af38f..249ceb0e637 100644
--- a/tests/helpers/test_service_info.py
+++ b/tests/helpers/test_service_info.py
@@ -1,14 +1,23 @@
 """Test service_info helpers."""
 
+import pytest
+
 from homeassistant.helpers.service_info.dhcp import DhcpServiceInfo
 
-# Ensure that DhcpServiceInfo.__post_init__ is called, even on a constant outside of a test
+# Ensure that incorrectly formatted mac addresses are rejected, even
+# on a constant outside of a test
 try:
     _ = DhcpServiceInfo(ip="", hostname="", macaddress="AA:BB:CC:DD:EE:FF")
 except ValueError:
     pass
 else:
     raise RuntimeError(
-        "DhcpServiceInfo.__post_init__ was not called. "
-        "Please ensure that the __post_init__ method is correctly defined."
+        "DhcpServiceInfo incorrectly formatted mac address was not rejected. "
+        "Please ensure that the DhcpServiceInfo is correctly patched."
     )
+
+
+def test_invalid_macaddress() -> None:
+    """Test that DhcpServiceInfo raises ValueError for unformatted macaddress."""
+    with pytest.raises(ValueError):
+        DhcpServiceInfo(ip="", hostname="", macaddress="AA:BB:CC:DD:EE:FF")