home-assistant · karwosts · Jun 30, 2025 · Jul 7, 2025 · Jul 8, 2025
@@ -2,6 +2,8 @@
 
 from __future__ import annotations
 
+import logging
+
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import CONF_SOURCE, Platform
 from homeassistant.core import HomeAssistant
@@ -11,6 +13,8 @@
 )
 from homeassistant.helpers.helper_integration import async_handle_source_entity_changes
 
+_LOGGER = logging.getLogger(__name__)
+
 
 async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
     """Set up Derivative from a config entry."""
@@ -54,3 +58,37 @@ async def config_entry_update_listener(hass: HomeAssistant, entry: ConfigEntry)
 async def async_unload_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
     """Unload a config entry."""
     return await hass.config_entries.async_unload_platforms(entry, (Platform.SENSOR,))
+
+
+async def async_migrate_entry(hass: HomeAssistant, config_entry: ConfigEntry) -> bool:
+    """Migrate old entry."""
+
+    _LOGGER.debug(
+        "Migrating configuration from version %s.%s",
+        config_entry.version,
+        config_entry.minor_version,
+    )
+
+    if config_entry.version > 1:
+        # This means the user has downgraded from a future version
+        return False
+
+    if config_entry.version == 1:
+        if config_entry.minor_version < 2:
+            new_options = {**config_entry.options}
+
+            if new_options.get("unit_prefix") == "none":
+                # Before we had support for optional selectors, "none" was used for selecting nothing
+                del new_options["unit_prefix"]
+
+            hass.config_entries.async_update_entry(
+                config_entry, options=new_options, version=1, minor_version=2
+            )
+
+ 
8000
   _LOGGER.debug(
+        "Migration to configuration version %s.%s successful",
+        config_entry.version,
+        config_entry.minor_version,
+    )
+
+    return True
@@ -140,6 +140,9 @@ class ConfigFlowHandler(SchemaConfigFlowHandler, domain=DOMAIN):
     config_flow = CONFIG_FLOW
     options_flow = OPTIONS_FLOW
 
+    VERSION = 1
+    MINOR_VERSION = 2
+
     def async_config_entry_title(self, options: Mapping[str, Any]) -> str:
         """Return config entry title."""
         return cast(str, options[CONF_NAME])
@@ -123,10 +123,6 @@ async def async_setup_entry(
         source_entity_id,
     )
 
-    if (unit_prefix := config_entry.options.get(CONF_UNIT_PREFIX)) == "none":
-        # Before we had support for optional selectors, "none" was used for selecting nothing
-        unit_prefix = None
-
     if max_sub_interval_dict := config_entry.options.get(CONF_MAX_SUB_INTERVAL, None):
         max_sub_interval = cv.time_period(max_sub_interval_dict)
     else:
@@ -139,7 +135,7 @@ async def async_setup_entry(
         time_window=cv.time_period_dict(config_entry.options[CONF_TIME_WINDOW]),
         unique_id=config_entry.entry_id,
         unit_of_measurement=None,
-        unit_prefix=unit_prefix,
+        unit_prefix=config_entry.options.get(CONF_UNIT_PREFIX),
         unit_time=config_entry.options[CONF_UNIT_TIME],
         device_info=device_info,
         max_sub_interval=max_sub_interval,

@@ -7,7 +7,7 @@
 from homeassistant.components import derivative
 from homeassistant.components.derivative.config_flow import ConfigFlowHandler
 from homeassistant.components.derivative.const import DOMAIN
-from homeassistant.config_entries import ConfigEntry
+from homeassistant.config_entries import ConfigEntry, ConfigEntryState
 from homeassistant.core import Event, HomeAssistant
 from homeassistant.helpers import device_registry as dr, entity_registry as er
 from homeassistant.helpers.event import async_track_entity_registry_updated_event
@@ -418,3 +418,65 @@ async def test_async_handle_source_entity_new_entity_id(
 
     # Check we got the expected events
     assert events == []
+
+
+@pytest.mark.parametrize(
+    ("unit_prefix", "expect_prefix"),
+    [
+        ({}, None),
+        ({"unit_prefix": "k"}, "k"),
+        ({"unit_prefix": "none"}, None),
+    ],
+)
+async def test_migration(hass: HomeAssistant, unit_prefix, expect_prefix) -> None:
+    """Test migration from v1.1 deletes "none" unit_prefix."""
+
+    config_entry = MockConfigEntry(
+        data={},
+        domain=DOMAIN,
+        options={
+            "name": "My derivative",
+            "round": 1.0,
+            "source": "sensor.power",
+            "time_window": {"seconds": 0.0},
+            **unit_prefix,
+            "unit_time": "min",
+        },
+        title="My derivative",
+        version=1,
+        minor_version=1,
+    )
+    config_entry.add_to_hass(hass)
+    await hass.config_entries.async_setup(config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    assert config_entry.state is ConfigEntryState.LOADED
+    assert config_entry.options["unit_time"] == "min"
+    assert config_entry.options.get("unit_prefix") == expect_prefix
+
+
+async def test_migration_from_future_version(
+    hass: HomeAssistant,
+) -> None:
+    """Test migration from future version."""
+
+    config_entry = MockConfigEntry(
+        data={},
+        domain=DOMAIN,
+        options={
+            "name": "My derivative",
+            "round": 1.0,
+            "source": "sensor.power",
+            "time_window": {"seconds": 0.0},
+            "unit_prefix": "k",
+            "unit_time": "min",
+        },
+        title="My derivative",
+        version=2,
+        minor_version=1,
+    )
+    config_entry.add_to_hass(hass)
+    await hass.config_entries.async_setup(config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    assert config_entry.state is ConfigEntryState.MIGRATION_ERROR