Allow components with empty list config (i.e. person) in packages (#25827)

* Fix #23424

* mypy Lists

homeassistant/config.py

@@ -631,10 +631,9 @@ def _recursive_merge(conf: Dict[str, Any], package: Dict[str, Any]) -> Union[boo
             error = _recursive_merge(conf=conf[key], package=pack_conf)
 
         elif isinstance(pack_conf, list):
-            if not pack_conf:
-                continue
-            conf[key] = cv.ensure_list(conf.get(key))
-            conf[key].extend(cv.ensure_list(pack_conf))
+            conf[key] = cv.remove_falsy(
+                cv.ensure_list(conf.get(key)) + cv.ensure_list(pack_conf)
+            )
 
         else:
             if conf.get(key) is not None:
@@ -669,21 +668,16 @@ async def merge_packages_config(
                 _log_pkg_error(pack_name, comp_name, config, str(ex))
                 continue
 
-            if hasattr(component, "PLATFORM_SCHEMA"):
-                if not comp_conf:
-                    continue  # Ensure we dont add Falsy items to list
-                config[comp_name] = cv.ensure_list(config.get(comp_name))
-                config[comp_name].extend(cv.ensure_list(comp_conf))
-                continue
+            merge_list = hasattr(component, "PLATFORM_SCHEMA")
 
-            if hasattr(component, "CONFIG_SCHEMA"):
+            if not merge_list and hasattr(component, "CONFIG_SCHEMA"):
                 merge_type, _ = _identify_config_schema(component)
+                merge_list = merge_type == "list"
 
-                if merge_type == "list":
-                    if not comp_conf:
-                        continue  # Ensure we dont add Falsy items to list
-                    config[comp_name] = cv.ensure_list(config.get(comp_name))
-                    config[comp_name].extend(cv.ensure_list(comp_conf))
+            if merge_list:
+                config[comp_name] = cv.remove_falsy(
+                    cv.ensure_list(config.get(comp_name)) + cv.ensure_list(comp_conf)
+                )
                 continue
 
             if comp_conf is None:

homeassistant/helpers/config_validation.py

@@ -11,7 +11,7 @@ from datetime import (
 )
 from socket import _GLOBAL_DEFAULT_TIMEOUT
 from numbers import Number
-from typing import Any, Union, TypeVar, Callable, Sequence, Dict, Optional
+from typing import Any, Union, TypeVar, Callable, List, Dict, Optional
 from urllib.parse import urlparse
 from uuid import UUID
 
@@ -191,7 +191,7 @@ def isdir(value: Any) -> str:
     return dir_in
 
 
-def ensure_list(value: Union[T, Sequence[T], None]) -> Sequence[T]:
+def ensure_list(value: Union[T, List[T], None]) -> List[T]:
     """Wrap value in list if it is not one."""
     if value is None:
         return []
@@ -207,7 +207,7 @@ def entity_id(value: Any) -> str:
     raise vol.Invalid("Entity ID {} is an invalid entity id".format(value))
 
 
-def entity_ids(value: Union[str, Sequence]) -> Sequence[str]:
+def entity_ids(value: Union[str, List]) -> List[str]:
     """Validate Entity IDs."""
     if value is None:
         raise vol.Invalid("Entity IDs can not be None")
@@ -234,7 +234,7 @@ def entity_domain(domain: str):
 def entities_domain(domain: str):
     """Validate that entities belong to domain."""
 
-    def validate(values: Union[str, Sequence]) -> Sequence[str]:
+    def validate(values: Union[str, List]) -> List[str]:
         """Test if entity domain is domain."""
         values = entity_ids(values)
         for ent_id in values:
@@ -370,7 +370,7 @@ def positive_timedelta(value: timedelta) -> timedelta:
     return value
 
 
-def remove_falsy(value: Sequence[T]) -> Sequence[T]:
+def remove_falsy(value: List[T]) -> List[T]:
     """Remove falsy values from a list."""
     return [v for v in value if v]
 
@@ -562,7 +562,7 @@ def uuid4_hex(value):
     return result.hex
 
 
-def ensure_list_csv(value: Any) -> Sequence:
+def ensure_list_csv(value: Any) -> List:
     """Ensure that input is a list or make one from comma-separated string."""
     if isinstance(value, str):
         return [member.strip() for member in value.split(",")]

tests/test_config.py

@@ -735,7 +735,7 @@ async def test_merge_once_only_lists(hass):
     """Test if we have a merge for a comp that may occur only once. Lists."""
     packages = {
         "pack_2": {
-            "api": {"list_1": ["item_2", "item_3"], "list_2": ["item_1"], "list_3": []}
+            "api": {"list_1": ["item_2", "item_3"], "list_2": ["item_4"], "list_3": []}
         }
     }
     config = {
@@ -745,7 +745,8 @@ async def test_merge_once_only_lists(hass):
     await config_util.merge_packages_config(hass, config, packages)
     assert config["api"] == {
         "list_1": ["item_1", "item_2", "item_3"],
-        "list_2": ["item_1"],
+        "list_2": ["item_4"],
+        "list_3": [],
     }