From 458fcc63723a6b2db9d73535230e7ba0478653a5 Mon Sep 17 00:00:00 2001
From: Michael <35783820+mib1185@users.noreply.github.com>
Date: Tue, 19 Dec 2023 09:58:02 +0100
Subject: [PATCH] Add significant Change support for alarm control panel
 (#106021)

---
 .../alarm_control_panel/significant_change.py | 38 ++++++++++++++
 .../test_significant_change.py                | 51 +++++++++++++++++++
 2 files changed, 89 insertions(+)
 create mode 100644 homeassistant/components/alarm_control_panel/significant_change.py
 create mode 100644 tests/components/alarm_control_panel/test_significant_change.py

diff --git a/homeassistant/components/alarm_control_panel/significant_change.py b/homeassistant/components/alarm_control_panel/significant_change.py
new file mode 100644
index 00000000000000..d33347a67f1db3
--- /dev/null
+++ b/homeassistant/components/alarm_control_panel/significant_change.py
@@ -0,0 +1,38 @@
+"""Helper to test significant Alarm Control Panel state changes."""
+from __future__ import annotations
+
+from typing import Any
+
+from homeassistant.core import HomeAssistant, callback
+
+from . import ATTR_CHANGED_BY, ATTR_CODE_ARM_REQUIRED
+
+SIGNIFICANT_ATTRIBUTES: set[str] = {
+    ATTR_CHANGED_BY,
+    ATTR_CODE_ARM_REQUIRED,
+}
+
+
+@callback
+def async_check_significant_change(
+    hass: HomeAssistant,
+    old_state: str,
+    old_attrs: dict,
+    new_state: str,
+    new_attrs: dict,
+    **kwargs: Any,
+) -> bool | None:
+    """Test if state significantly changed."""
+    if old_state != new_state:
+        return True
+
+    old_attrs_s = set(old_attrs.items())
+    new_attrs_s = set(new_attrs.items())
+    changed_attrs: set[str] = {item[0] for item in old_attrs_s ^ new_attrs_s}
+
+    for attr_name in changed_attrs:
+        if attr_name in SIGNIFICANT_ATTRIBUTES:
+            return True
+
+    # no significant attribute change detected
+    return False
diff --git a/tests/components/alarm_control_panel/test_significant_change.py b/tests/components/alarm_control_panel/test_significant_change.py
new file mode 100644
index 00000000000000..d65a1d5cb00c77
--- /dev/null
+++ b/tests/components/alarm_control_panel/test_significant_change.py
@@ -0,0 +1,51 @@
+"""Test the Alarm Control Panel significant change platform."""
+import pytest
+
+from homeassistant.components.alarm_control_panel import (
+    ATTR_CHANGED_BY,
+    ATTR_CODE_ARM_REQUIRED,
+    ATTR_CODE_FORMAT,
+)
+from homeassistant.components.alarm_control_panel.significant_change import (
+    async_check_significant_change,
+)
+
+
+async def test_significant_state_change() -> None:
+    """Detect Alarm Control Panel significant state changes."""
+    attrs = {}
+    assert not async_check_significant_change(None, "on", attrs, "on", attrs)
+    assert async_check_significant_change(None, "on", attrs, "off", attrs)
+
+
+@pytest.mark.parametrize(
+    ("old_attrs", "new_attrs", "expected_result"),
+    [
+        ({ATTR_CHANGED_BY: "old_value"}, {ATTR_CHANGED_BY: "old_value"}, False),
+        ({ATTR_CHANGED_BY: "old_value"}, {ATTR_CHANGED_BY: "new_value"}, True),
+        (
+            {ATTR_CODE_ARM_REQUIRED: "old_value"},
+            {ATTR_CODE_ARM_REQUIRED: "new_value"},
+            True,
+        ),
+        # multiple attributes
+        (
+            {ATTR_CHANGED_BY: "old_value", ATTR_CODE_ARM_REQUIRED: "old_value"},
+            {ATTR_CHANGED_BY: "new_value", ATTR_CODE_ARM_REQUIRED: "old_value"},
+            True,
+        ),
+        # insignificant attributes
+        ({ATTR_CODE_FORMAT: "old_value"}, {ATTR_CODE_FORMAT: "old_value"}, False),
+        ({ATTR_CODE_FORMAT: "old_value"}, {ATTR_CODE_FORMAT: "new_value"}, False),
+        ({"unknown_attr": "old_value"}, {"unknown_attr": "old_value"}, False),
+        ({"unknown_attr": "old_value"}, {"unknown_attr": "new_value"}, False),
+    ],
+)
+async def test_significant_atributes_change(
+    old_attrs: dict, new_attrs: dict, expected_result: bool
+) -> None:
+    """Detect Humidifier significant attribute changes."""
+    assert (
+        async_check_significant_change(None, "state", old_attrs, "state", new_attrs)
+        == expected_result
+    )