Tessie: log warning instead of raising UpdateFailed for missing energy history (#168068)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

homeassistant/components/tessie/coordinator.py

@@ -224,10 +224,11 @@ class TessieEnergyHistoryCoordinator(DataUpdateCoordinator[dict[str, Any]]):
             or not isinstance(data.get("time_series"), list)
             or not data["time_series"]
         ):
-            raise UpdateFailed(
-                translation_domain=DOMAIN,
-                translation_key="invalid_energy_history_data",
+            _LOGGER.warning(
+                "Tessie returned no energy history time_series for coordinator %s; skipping update",
+                self.config_entry.entry_id,
             )
+            return self.data
 
         time_series = data["time_series"]
         output: dict[str, Any] = {}

homeassistant/components/tessie/sensor.py

@@ -638,4 +638,4 @@ class TessieEnergyHistorySensorEntity(TessieEnergyHistoryEntity, SensorEntity):
         """Update the attributes of the sensor."""
         self._attr_available = self._value is not None
         self._attr_native_value = self._value
-        self._attr_last_reset = self.coordinator.data["_period_start"]
+        self._attr_last_reset = self.coordinator.data.get("_period_start")

tests/components/tessie/test_coordinator.py

@@ -1,5 +1,6 @@
 """Test the Tessie sensor platform."""
 
+from copy import deepcopy
 from datetime import timedelta
 
 from freezegun.api import FrozenDateTimeFactory
@@ -14,11 +15,17 @@ from homeassistant.components.tessie.coordinator import (
     TESSIE_SYNC_INTERVAL,
 )
 from homeassistant.config_entries import ConfigEntryState
-from homeassistant.const import STATE_ON, STATE_UNAVAILABLE, Platform
+from homeassistant.const import STATE_ON, STATE_UNAVAILABLE, STATE_UNKNOWN, Platform
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.update_coordinator import UpdateFailed
 
-from .common import ERROR_AUTH, ERROR_CONNECTION, ERROR_UNKNOWN, setup_platform
+from .common import (
+    ENERGY_HISTORY,
+    ERROR_AUTH,
+    ERROR_CONNECTION,
+    ERROR_UNKNOWN,
+    setup_platform,
+)
 
 from tests.common import async_fire_time_changed
 
@@ -184,21 +191,52 @@ async def test_coordinator_energy_history_error(
 async def test_coordinator_energy_history_invalid_data(
     hass: HomeAssistant, mock_energy_history, freezer: FrozenDateTimeFactory
 ) -> None:
-    """Tests that the energy history coordinator handles invalid data."""
+    """Tests that the energy history coordinator handles invalid data gracefully."""
 
     entry = await setup_platform(hass, [Platform.SENSOR])
     coordinator = entry.runtime_data.energysites[0].history_coordinator
     assert coordinator is not None
 
+    # Capture state after successful initial load
+    state_before = hass.states.get("sensor.energy_site_grid_imported").state
+
     mock_energy_history.reset_mock()
     mock_energy_history.side_effect = lambda *a, **kw: {"response": {}}
     freezer.tick(TESSIE_ENERGY_HISTORY_INTERVAL)
     async_fire_time_changed(hass)
     await hass.async_block_till_done()
     mock_energy_history.assert_called_once()
-    assert (
-        hass.states.get("sensor.energy_site_grid_imported").state == STATE_UNAVAILABLE
-    )
-    assert isinstance(coordinator.last_exception, UpdateFailed)
-    assert coordinator.last_exception.translation_domain == DOMAIN
-    assert coordinator.last_exception.translation_key == "invalid_energy_history_data"
+
+    # Sensor should retain last good state rather than becoming unavailable
+    assert hass.states.get("sensor.energy_site_grid_imported").state == state_before
+    assert coordinator.last_exception is None
+
+
+async def test_coordinator_energy_history_cold_start_invalid_data(
+    hass: HomeAssistant, mock_energy_history, freezer: FrozenDateTimeFactory
+) -> None:
+    """Tests cold-start fallback when the very first energy history fetch has invalid data."""
+
+    mock_energy_history.side_effect = lambda *a, **kw: {"response": {}}
+    entry = await setup_platform(hass, [Platform.SENSOR])
+    coordinator = entry.runtime_data.energysites[0].history_coordinator
+    assert coordinator is not None
+
+    # Coordinator should not have raised an exception; data stays empty
+    assert coordinator.last_exception is None
+    assert coordinator.data == {}
+
+    # Sensor should be unknown until the first successful fetch
+    assert hass.states.get("sensor.energy_site_grid_imported").state == STATE_UNKNOWN
+
+    # Now recover: restore valid energy history data and trigger an update
+    mock_energy_history.side_effect = lambda *a, **kw: deepcopy(ENERGY_HISTORY)
+    mock_energy_history.reset_mock()
+    freezer.tick(TESSIE_ENERGY_HISTORY_INTERVAL)
+    async_fire_time_changed(hass)
+    await hass.async_block_till_done()
+    mock_energy_history.assert_called_once()
+
+    # Coordinator should have real data and no exception
+    assert coordinator.last_exception is None
+    assert coordinator.data["solar_energy_exported"] == 724