Refactor

homeassistant/bootstrap.py

@@ -100,7 +100,6 @@ async def async_setup_hass(
 ) -> core.HomeAssistant | None:
     """Set up Home Assistant."""
     hass = core.HomeAssistant()
-    core._cv_hass.set(hass)  # pylint: disable=protected-access
     hass.config.config_dir = runtime_config.config_dir
 
     async_enable_logging(
@@ -166,6 +165,7 @@ async def async_setup_hass(
         old_config = hass.config
         old_logging = hass.data.get(DATA_LOGGING)
 
+        core._cv_hass.reset(hass._context_token)  # pylint: disable=protected-access
         hass = core.HomeAssistant()
         if old_logging:
             hass.data[DATA_LOGGING] = old_logging

homeassistant/core.py

@@ -15,7 +15,7 @@ from collections.abc import (
     Iterable,
     Mapping,
 )
-from contextvars import ContextVar
+from contextvars import ContextVar, Token
 import datetime
 import enum
 import functools
@@ -178,12 +178,6 @@ def is_callback(func: Callable[..., Any]) -> bool:
     return getattr(func, "_hass_callback", False) is True
 
 
-@callback
-def async_get_hass() -> HomeAssistant:
-    """Return the HomeAssistant instance."""
-    return _cv_hass.get()
-
-
 @enum.unique
 class HassJobType(enum.Enum):
     """Represent a job type."""
@@ -250,9 +244,23 @@ class HomeAssistant:
     auth: AuthManager
     http: HomeAssistantHTTP = None  # type: ignore[assignment]
     config_entries: ConfigEntries = None  # type: ignore[assignment]
+    _initialized: bool = False
+    _context_token: Token[HomeAssistant]
+
+    def __new__(cls) -> HomeAssistant:
+        """Return the existing HA instance if it exists, otherwise create one."""
+        try:
+            return _cv_hass.get()
+        except LookupError:
+            hass = super().__new__(cls)
+            hass._context_token = _cv_hass.set(hass)
+            return hass
 
     def __init__(self) -> None:
         """Initialize new Home Assistant object."""
+        if self._initialized:
+            return
+        self._initialized = True
         self.loop = asyncio.get_running_loop()
         self._pending_tasks: list[asyncio.Future[Any]] = []
         self._track_task = True

tests/test_bootstrap.py

@@ -501,7 +501,7 @@ async def test_setup_hass(
     assert len(mock_ensure_config_exists.mock_calls) == 1
     assert len(mock_process_ha_config_upgrade.mock_calls) == 1
 
-    assert hass == core.async_get_hass()
+    assert hass == core.HomeAssistant()
 
 
 async def test_setup_hass_takes_longer_than_log_slow_startup(