Fix zeroconf when location name has a period (#81022)

homeassistant/components/zeroconf/__init__.py

@@ -234,12 +234,20 @@ def _get_announced_addresses(
     return address_list
 
 
+def _filter_disallowed_characters(name: str) -> str:
+    """Filter disallowed characters from a string.
+
+    . is a reversed character for zeroconf.
+    """
+    return name.replace(".", " ")
+
+
 async def _async_register_hass_zc_service(
     hass: HomeAssistant, aio_zc: HaAsyncZeroconf, uuid: str
 ) -> None:
     # Get instance UUID
     valid_location_name = _truncate_location_name_to_valid(
-        hass.config.location_name or "Home"
+        _filter_disallowed_characters(hass.config.location_name or "Home")
     )
 
     params = {

tests/components/zeroconf/test_init.py

@@ -1162,6 +1162,25 @@ async def test_no_name(hass, mock_async_zeroconf):
     assert info.name == "Home._home-assistant._tcp.local."
 
 
+async def test_setup_with_disallowed_characters_in_local_name(
+    hass, mock_async_zeroconf, caplog
+):
+    """Test we still setup with disallowed characters in the location name."""
+    with patch.object(hass.config_entries.flow, "async_init"), patch.object(
+        zeroconf, "HaAsyncServiceBrowser", side_effect=service_update_mock
+    ), patch.object(
+        hass.config,
+        "location_name",
+        "My.House",
+    ):
+        assert await async_setup_component(hass, zeroconf.DOMAIN, {zeroconf.DOMAIN: {}})
+        hass.bus.async_fire(EVENT_HOMEASSISTANT_START)
+        await hass.async_block_till_done()
+
+    calls = mock_async_zeroconf.async_register_service.mock_calls
+    assert calls[0][1][0].name == "My House._home-assistant._tcp.local."
+
+
 async def test_start_with_frontend(hass, mock_async_zeroconf):
     """Test we start with the frontend."""
     with patch("homeassistant.components.zeroconf.HaZeroconf"):