empty name uses device name, use get_base_entity_object_id

esphome/core/entity_helpers.py

@@ -187,8 +187,17 @@ def entity_duplicate_validator(platform: str) -> Callable[[ConfigType], ConfigTy
         # Get the entity name
         entity_name = config[CONF_NAME]
 
-        # For duplicate detection, just use the sanitized name
-        name_key = sanitize(snake_case(entity_name))
+        # Get device name if entity is on a sub-device
+        device_name = None
+        if CONF_DEVICE_ID in config:
+            device_id_obj = config[CONF_DEVICE_ID]
+            device_name = device_id_obj.id
+
+        # Calculate what object_id will actually be used
+        # This handles empty names correctly by using device/friendly names
+        name_key = get_base_entity_object_id(
+            entity_name, CORE.friendly_name, device_name
+        )
 
         # Check for duplicates
         unique_key = (platform, name_key)

tests/integration/fixtures/duplicate_entities_not_allowed_on_different_devices.yaml

@@ -133,7 +133,35 @@ button:
     name: "Reset Main"
     on_press: []  # Main device
 
-# Scenario 6: Special characters in names - now with unique names
+# Scenario 6: Empty names (should use device names)
+select:
+  - platform: template
+    name: ""
+    device_id: controller_1
+    options:
+      - "Option 1"
+      - "Option 2"
+    lambda: return {"Option 1"};
+    set_action: []
+
+  - platform: template
+    name: ""
+    device_id: controller_2
+    options:
+      - "Option 1"
+      - "Option 2"
+    lambda: return {"Option 1"};
+    set_action: []
+
+  - platform: template
+    name: ""  # Main device
+    options:
+      - "Option 1"
+      - "Option 2"
+    lambda: return {"Option 1"};
+    set_action: []
+
+# Scenario 7: Special characters in names - now with unique names
 number:
   - platform: template
     name: "Temperature Setpoint! Controller 1"

tests/integration/test_duplicate_entities.py

@@ -52,6 +52,7 @@ async def test_duplicate_entities_not_allowed_on_different_devices(
         switches = [e for e in all_entities if e.__class__.__name__ == "SwitchInfo"]
         buttons = [e for e in all_entities if e.__class__.__name__ == "ButtonInfo"]
         numbers = [e for e in all_entities if e.__class__.__name__ == "NumberInfo"]
+        selects = [e for e in all_entities if e.__class__.__name__ == "SelectInfo"]
 
         # Scenario 1: Check that temperature sensors have unique names per device
         temp_sensors = [s for s in sensors if "Temperature" in s.name]
@@ -144,7 +145,28 @@ async def test_duplicate_entities_not_allowed_on_different_devices(
             f"Reset buttons should have unique names, got {reset_names}"
         )
 
-        # Scenario 7: Check special characters in number names - now unique
+        # Scenario 7: Check empty name selects (should use device names)
+        empty_selects = [s for s in selects if s.name == ""]
+        assert len(empty_selects) == 3, (
+            f"Expected exactly 3 empty name selects, got {len(empty_selects)}"
+        )
+
+        # Group by device
+        c1_selects = [s for s in empty_selects if s.device_id == controller_1.device_id]
+        c2_selects = [s for s in empty_selects if s.device_id == controller_2.device_id]
+
+        # For main device, device_id is 0
+        main_selects = [s for s in empty_selects if s.device_id == 0]
+
+        # Check object IDs for empty name entities - they should use device names
+        assert len(c1_selects) == 1 and c1_selects[0].object_id == "controller_1"
+        assert len(c2_selects) == 1 and c2_selects[0].object_id == "controller_2"
+        assert (
+            len(main_selects) == 1
+            and main_selects[0].object_id == "duplicate-entities-test"
+        )
+
+        # Scenario 8: Check special characters in number names - now unique
         temp_numbers = [n for n in numbers if "Temperature Setpoint!" in n.name]
         assert len(temp_numbers) == 2, (
             f"Expected exactly 2 temperature setpoint numbers, got {len(temp_numbers)}"
@@ -170,6 +192,7 @@ async def test_duplicate_entities_not_allowed_on_different_devices(
             + len(switches)
             + len(buttons)
             + len(numbers)
+            + len(selects)
         )
 
         def on_state(state) -> None:

tests/unit_tests/core/test_entity_helpers.py

@@ -555,6 +555,17 @@ def test_entity_duplicate_validator_with_devices() -> None:
     assert validated3 == config3
     assert ("sensor", "humidity") in CORE.unique_ids
 
+    # Empty names should use device names and be allowed
+    config4 = {CONF_NAME: "", CONF_DEVICE_ID: device1}
+    validated4 = validator(config4)
+    assert validated4 == config4
+    assert ("sensor", "device1") in CORE.unique_ids
+
+    config5 = {CONF_NAME: "", CONF_DEVICE_ID: device2}
+    validated5 = validator(config5)
+    assert validated5 == config5
+    assert ("sensor", "device2") in CORE.unique_ids
+
 
 def test_duplicate_entity_yaml_validation(
     yaml_file: Callable[[str], str], capsys: pytest.CaptureFixture[str]