Fix saving a scene (#49980)

Co-authored-by: Paulus Schoutsen <balloob@gmail.com>

homeassistant/components/config/scene.py

@@ -1,5 +1,4 @@
 """Provide configuration end points for Scenes."""
-from collections import OrderedDict
 import uuid
 
 from homeassistant.components.scene import DOMAIN, PLATFORM_SCHEMA
@@ -48,24 +47,9 @@ class EditSceneConfigView(EditIdBasedConfigView):
 
     def _write_value(self, hass, data, config_key, new_value):
         """Set value."""
-        index = None
-        for index, cur_value in enumerate(data):
-            # When people copy paste their scenes to the config file,
-            # they sometimes forget to add IDs. Fix it here.
-            if CONF_ID not in cur_value:
-                cur_value[CONF_ID] = uuid.uuid4().hex
-
-            elif cur_value[CONF_ID] == config_key:
-                break
-        else:
-            cur_value = {}
-            cur_value[CONF_ID] = config_key
-            index = len(data)
-            data.append(cur_value)
-
         # Iterate through some keys that we want to have ordered in the output
-        updated_value = OrderedDict()
-        for key in ("id", "name", "entities"):
+        updated_value = {CONF_ID: config_key}
+        for key in ("name", "entities"):
             if key in new_value:
                 updated_value[key] = new_value[key]
 
@@ -73,4 +57,16 @@ class EditSceneConfigView(EditIdBasedConfigView):
         # supporting more fields in the future.
         updated_value.update(new_value)
 
-        data[index] = updated_value
+        updated = False
+        for index, cur_value in enumerate(data):
+            # When people copy paste their scenes to the config file,
+            # they sometimes forget to add IDs. Fix it here.
+            if CONF_ID not in cur_value:
+                cur_value[CONF_ID] = uuid.uuid4().hex
+
+            elif cur_value[CONF_ID] == config_key:
+                data[index] = updated_value
+                updated = True
+
+        if not updated:
+            data.append(updated_value)

tests/components/config/test_scene.py

@@ -8,6 +8,55 @@ from homeassistant.helpers import entity_registry as er
 from homeassistant.util.yaml import dump
 
 
+async def test_create_scene(hass, hass_client):
+    """Test creating a scene."""
+    with patch.object(config, "SECTIONS", ["scene"]):
+        await async_setup_component(hass, "config", {})
+
+    client = await hass_client()
+
+    def mock_read(path):
+        """Mock reading data."""
+        return None
+
+    written = []
+
+    def mock_write(path, data):
+        """Mock writing data."""
+        data = dump(data)
+        written.append(data)
+
+    with patch("homeassistant.components.config._read", mock_read), patch(
+        "homeassistant.components.config._write", mock_write
+    ), patch("homeassistant.config.async_hass_config_yaml", return_value={}):
+        resp = await client.post(
+            "/api/config/scene/config/light_off",
+            data=json.dumps(
+                {
+                    # "id": "light_off",
+                    "name": "Lights off",
+                    "entities": {"light.bedroom": {"state": "off"}},
+                }
+            ),
+        )
+
+    assert resp.status == 200
+    result = await resp.json()
+    assert result == {"result": "ok"}
+
+    assert len(written) == 1
+    written_yaml = written[0]
+    assert (
+        written_yaml
+        == """- id: light_off
+  name: Lights off
+  entities:
+    light.bedroom:
+      state: 'off'
+"""
+    )
+
+
 async def test_update_scene(hass, hass_client):
     """Test updating a scene."""
     with patch.object(config, "SECTIONS", ["scene"]):