Make the device_tracker more forgiving when passed an empty ip address string (#91101)

This has come up over and over and over again

fixes #87165 fixes #51980

homeassistant/components/device_tracker/config_entry.py

@@ -348,7 +348,7 @@ class ScannerEntity(BaseTrackerEntity):
                 self.mac_address,
                 self.unique_id,
             )
-            if self.is_connected:
+            if self.is_connected and self.ip_address:
                 _async_connected_device_registered(
                     hass,
                     self.mac_address,
@@ -405,7 +405,7 @@ class ScannerEntity(BaseTrackerEntity):
         """Return the device state attributes."""
         attr: dict[str, StateType] = {}
         attr.update(super().state_attributes)
-        if self.ip_address is not None:
+        if self.ip_address:
             attr[ATTR_IP] = self.ip_address
         if self.mac_address is not None:
             attr[ATTR_MAC] = self.mac_address

tests/components/device_tracker/test_config_entry.py

@@ -195,21 +195,6 @@ async def test_connected_device_registered(
     class MockDisconnectedScannerEntity(MockScannerEntity):
         """Mock a disconnected scanner entity."""
 
-        @property
-        def mac_address(self) -> str:
-            return "aa:bb:cc:dd:ee:ff"
-
-        @property
-        def is_connected(self) -> bool:
-            return True
-
-        @property
-        def hostname(self) -> str:
-            return "connected"
-
-    class MockConnectedScannerEntity(MockScannerEntity):
-        """Mock a disconnected scanner entity."""
-
         @property
         def mac_address(self) -> str:
             return "aa:bb:cc:dd:ee:00"
@@ -222,10 +207,44 @@ async def test_connected_device_registered(
         def hostname(self) -> str:
             return "disconnected"
 
+    class MockConnectedScannerEntity(MockScannerEntity):
+        """Mock a disconnected scanner entity."""
+
+        @property
+        def mac_address(self) -> str:
+            return "aa:bb:cc:dd:ee:ff"
+
+        @property
+        def is_connected(self) -> bool:
+            return True
+
+        @property
+        def hostname(self) -> str:
+            return "connected"
+
+    class MockConnectedScannerEntityBadIPAddress(MockConnectedScannerEntity):
+        """Mock a disconnected scanner entity."""
+
+        @property
+        def mac_address(self) -> str:
+            return "aa:bb:cc:dd:ee:01"
+
+        @property
+        def ip_address(self) -> str:
+            return ""
+
+        @property
+        def hostname(self) -> str:
+            return "connected_bad_ip"
+
     async def async_setup_entry(hass, config_entry, async_add_entities):
         """Mock setup entry method."""
         async_add_entities(
-            [MockConnectedScannerEntity(), MockDisconnectedScannerEntity()]
+            [
+                MockConnectedScannerEntity(),
+                MockDisconnectedScannerEntity(),
+                MockConnectedScannerEntityBadIPAddress(),
+            ]
         )
         return True
 
@@ -240,7 +259,7 @@ async def test_connected_device_registered(
     full_name = f"{entity_platform.domain}.{config_entry.domain}"
     assert full_name in hass.config.components
     assert len(hass.states.async_entity_ids()) == 0  # should be disabled
-    assert len(entity_registry.entities) == 2
+    assert len(entity_registry.entities) == 3
     assert (
         entity_registry.entities["test_domain.test_aa_bb_cc_dd_ee_ff"].config_entry_id
         == "super-mock-id"