From d8c139f21126370c4a9574f045659fd1f86bdde4 Mon Sep 17 00:00:00 2001
From: G Johansson <goran.johansson@shiftit.se>
Date: Mon, 8 Jan 2024 09:31:44 +0100
Subject: [PATCH] Fix language flavors in holiday (#107392)

---
 homeassistant/components/holiday/calendar.py | 12 +++
 tests/components/holiday/test_calendar.py    | 85 ++++++++++++++++++++
 2 files changed, 97 insertions(+)

diff --git a/homeassistant/components/holiday/calendar.py b/homeassistant/components/holiday/calendar.py
index bb9a332cb73..e48cc11d677 100644
--- a/homeassistant/components/holiday/calendar.py
+++ b/homeassistant/components/holiday/calendar.py
@@ -43,6 +43,18 @@ async def async_setup_entry(
                 )
                 language = lang
                 break
+    if (
+        obj_holidays.supported_languages
+        and language not in obj_holidays.supported_languages
+        and (default_language := obj_holidays.default_language)
+    ):
+        obj_holidays = country_holidays(
+            country,
+            subdiv=province,
+            years={dt_util.now().year, dt_util.now().year + 1},
+            language=default_language,
+        )
+        language = default_language
 
     async_add_entities(
         [
diff --git a/tests/components/holiday/test_calendar.py b/tests/components/holiday/test_calendar.py
index 06011fb8e6b..df0ce6d50d5 100644
--- a/tests/components/holiday/test_calendar.py
+++ b/tests/components/holiday/test_calendar.py
@@ -227,3 +227,88 @@ async def test_no_next_event(
     assert state is not None
     assert state.state == "off"
     assert state.attributes == {"friendly_name": "Germany"}
+
+
+async def test_language_not_exist(
+    hass: HomeAssistant, freezer: FrozenDateTimeFactory
+) -> None:
+    """Test when language doesn't exist it will fallback to country default language."""
+
+    hass.config.language = "nb"  # Norweigan language "Norks bokmål"
+    hass.config.country = "NO"
+
+    freezer.move_to(datetime(2023, 1, 1, 12, tzinfo=dt_util.UTC))
+
+    config_entry = MockConfigEntry(
+        domain=DOMAIN,
+        data={CONF_COUNTRY: "NO"},
+        title="Norge",
+    )
+    config_entry.add_to_hass(hass)
+
+    await hass.config_entries.async_setup(config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    state = hass.states.get("calendar.norge")
+    assert state is not None
+    assert state.state == "on"
+    assert state.attributes == {
+        "friendly_name": "Norge",
+        "all_day": True,
+        "description": "",
+        "end_time": "2023-01-02 00:00:00",
+        "location": "Norge",
+        "message": "Første nyttårsdag",
+        "start_time": "2023-01-01 00:00:00",
+    }
+
+    response = await hass.services.async_call(
+        CALENDAR_DOMAIN,
+        SERVICE_GET_EVENTS,
+        {
+            "entity_id": "calendar.norge",
+            "end_date_time": dt_util.now(),
+        },
+        blocking=True,
+        return_response=True,
+    )
+    assert response == {
+        "calendar.norge": {
+            "events": [
+                {
+                    "start": "2023-01-01",
+                    "end": "2023-01-02",
+                    "summary": "Første nyttårsdag",
+                    "location": "Norge",
+                }
+            ]
+        }
+    }
+
+    # Test with English as exist as optional language for Norway
+    hass.config.language = "en"
+    hass.config.country = "NO"
+    await hass.config_entries.async_reload(config_entry.entry_id)
+    await hass.async_block_till_done()
+    response = await hass.services.async_call(
+        CALENDAR_DOMAIN,
+        SERVICE_GET_EVENTS,
+        {
+            "entity_id": "calendar.norge",
+            "end_date_time": dt_util.now(),
+        },
+        blocking=True,
+        return_response=True,
+    )
+    assert response == {
+        "calendar.norge": {
+            "events": [
+                {
+                    "start": "2023-01-01",
+                    "end": "2023-01-02",
+                    "summary": "New Year's Day",
+                    "location": "Norge",
+                }
+            ]
+        }
+    }