From 7a4a792b7bf23e42ec332cf17cebc140c8163c8c Mon Sep 17 00:00:00 2001
From: Erik Montnemery <erik@montnemery.com>
Date: Mon, 11 Sep 2023 14:33:43 +0200
Subject: [PATCH] Fix TriggerEntity.async_added_to_hass (#100119)

---
 .../components/template/trigger_entity.py     |  3 +-
 tests/components/template/test_sensor.py      | 44 ++++++++++++++++++-
 2 files changed, 44 insertions(+), 3 deletions(-)

diff --git a/homeassistant/components/template/trigger_entity.py b/homeassistant/components/template/trigger_entity.py
index ca2f7240086..5f5fbe5b99a 100644
--- a/homeassistant/components/template/trigger_entity.py
+++ b/homeassistant/components/template/trigger_entity.py
@@ -23,8 +23,7 @@ class TriggerEntity(TriggerBaseEntity, CoordinatorEntity[TriggerUpdateCoordinato
 
     async def async_added_to_hass(self) -> None:
         """Handle being added to Home Assistant."""
-        await TriggerBaseEntity.async_added_to_hass(self)
-        await CoordinatorEntity.async_added_to_hass(self)  # type: ignore[arg-type]
+        await super().async_added_to_hass()
         if self.coordinator.data is not None:
             self._process_data()
 
diff --git a/tests/components/template/test_sensor.py b/tests/components/template/test_sensor.py
index 1bd1e797c05..4010bb34d2d 100644
--- a/tests/components/template/test_sensor.py
+++ b/tests/components/template/test_sensor.py
@@ -1,7 +1,7 @@
 """The test for the Template sensor platform."""
 from asyncio import Event
 from datetime import timedelta
-from unittest.mock import patch
+from unittest.mock import ANY, patch
 
 import pytest
 
@@ -1140,6 +1140,48 @@ async def test_trigger_entity(
     assert state.context is context
 
 
+@pytest.mark.parametrize(("count", "domain"), [(1, "template")])
+@pytest.mark.parametrize(
+    "config",
+    [
+        {
+            "template": [
+                {
+                    "trigger": {"platform": "event", "event_type": "test_event"},
+                    "sensors": {
+                        "hello": {
+                            "friendly_name": "Hello Name",
+                            "value_template": "{{ trigger.event.data.beer }}",
+                            "entity_picture_template": "{{ '/local/dogs.png' }}",
+                            "icon_template": "{{ 'mdi:pirate' }}",
+                            "attribute_templates": {
+                                "last": "{{now().strftime('%D %X')}}",
+                                "history_1": "{{this.attributes.last|default('Not yet set')}}",
+                            },
+                        },
+                    },
+                },
+            ],
+        },
+    ],
+)
+async def test_trigger_entity_runs_once(
+    hass: HomeAssistant, start_ha, entity_registry: er.EntityRegistry
+) -> None:
+    """Test trigger entity handles a trigger once."""
+    state = hass.states.get("sensor.hello_name")
+    assert state is not None
+    assert state.state == STATE_UNKNOWN
+
+    hass.bus.async_fire("test_event", {"beer": 2})
+    await hass.async_block_till_done()
+
+    state = hass.states.get("sensor.hello_name")
+    assert state.state == "2"
+    assert state.attributes.get("last") == ANY
+    assert state.attributes.get("history_1") == "Not yet set"
+
+
 @pytest.mark.parametrize(("count", "domain"), [(1, "template")])
 @pytest.mark.parametrize(
     "config",