ESPHome: Use MAC as unique ID (#83741)

* ESPHome: Use MAC as unique ID

* Normalize incoming zeroconf/dhcp macs

* Update comment

* Test ESPHome without mac in zeroconf

* Use format_mac

* Remove unique ID index from DomainData

tests/components/esphome/test_init.py

@@ -0,0 +1,30 @@
+"""ESPHome set up tests."""
+from unittest.mock import AsyncMock
+
+from aioesphomeapi import DeviceInfo
+
+from homeassistant.components.esphome import DOMAIN
+from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_PORT
+
+from tests.common import MockConfigEntry
+
+
+async def test_unique_id_updated_to_mac(hass, mock_client, mock_zeroconf):
+    """Test we update config entry unique ID to MAC address."""
+    entry = MockConfigEntry(
+        domain=DOMAIN,
+        data={CONF_HOST: "test.local", CONF_PORT: 6053, CONF_PASSWORD: ""},
+        unique_id="mock-config-name",
+    )
+    entry.add_to_hass(hass)
+
+    mock_client.device_info = AsyncMock(
+        return_value=DeviceInfo(
+            mac_address="1122334455aa",
+        )
+    )
+
+    await hass.config_entries.async_setup(entry.entry_id)
+    await hass.async_block_till_done()
+
+    assert entry.unique_id == "11:22:33:44:55:aa"