Add discovery to NUT integration (#36827)

* Add discovery to NUT integration

* implement async_step_zeroconf

* Update test to make sure unique id not set

* Remove host/port import when coming from discovery, add title placeholders

* fix mis-paste

Co-authored-by: J. Nick Koston <nick@koston.org>

tests/components/nut/test_config_flow.py

@@ -1,4 +1,5 @@
 """Test the Network UPS Tools (NUT) config flow."""
+
 from homeassistant import config_entries, data_entry_flow, setup
 from homeassistant.components.nut.const import DOMAIN
 from homeassistant.const import CONF_RESOURCES, CONF_SCAN_INTERVAL
@@ -16,6 +17,59 @@ VALID_CONFIG = {
 }
 
 
+async def test_form_zeroconf(hass):
+    """Test we can setup from zeroconf."""
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN,
+        context={"source": config_entries.SOURCE_ZEROCONF},
+        data={"host": "192.168.1.5", "port": 1234},
+    )
+    assert result["type"] == data_entry_flow.RESULT_TYPE_FORM
+    assert result["step_id"] == "user"
+    assert result["errors"] == {}
+
+    mock_pynut = _get_mock_pynutclient(
+        list_vars={"battery.voltage": "voltage", "ups.status": "OL"}, list_ups=["ups1"]
+    )
+
+    with patch(
+        "homeassistant.components.nut.PyNUTClient", return_value=mock_pynut,
+    ):
+        result2 = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            {"username": "test-username", "password": "test-password"},
+        )
+
+    assert result2["step_id"] == "resources"
+    assert result2["type"] == "form"
+
+    with patch(
+        "homeassistant.components.nut.PyNUTClient", return_value=mock_pynut,
+    ), patch(
+        "homeassistant.components.nut.async_setup", return_value=True
+    ) as mock_setup, patch(
+        "homeassistant.components.nut.async_setup_entry", return_value=True,
+    ) as mock_setup_entry:
+        result3 = await hass.config_entries.flow.async_configure(
+            result2["flow_id"],
+            {"resources": ["battery.voltage", "ups.status", "ups.status.display"]},
+        )
+
+    assert result3["type"] == "create_entry"
+    assert result3["title"] == "192.168.1.5:1234"
+    assert result3["data"] == {
+        "host": "192.168.1.5",
+        "password": "test-password",
+        "port": 1234,
+        "resources": ["battery.voltage", "ups.status", "ups.status.display"],
+        "username": "test-username",
+    }
+    assert result3["result"].unique_id is None
+    await hass.async_block_till_done()
+    assert len(mock_setup.mock_calls) == 1
+    assert len(mock_setup_entry.mock_calls) == 1
+
+
 async def test_form_user_one_ups(hass):
     """Test we get the form."""
     await setup.async_setup_component(hass, "persistent_notification", {})