From 07a4422a704aafbb6d42b3155312b9dbbc3428b2 Mon Sep 17 00:00:00 2001
From: Nathan Tilley <nathan@tilley.xyz>
Date: Sat, 30 Jan 2021 02:05:58 -0500
Subject: [PATCH] Implement person significant change (#45713)

---
 .../components/person/significant_change.py   | 21 +++++++++++++++++++
 .../person/test_significant_change.py         | 16 ++++++++++++++
 2 files changed, 37 insertions(+)
 create mode 100644 homeassistant/components/person/significant_change.py
 create mode 100644 tests/components/person/test_significant_change.py

diff --git a/homeassistant/components/person/significant_change.py b/homeassistant/components/person/significant_change.py
new file mode 100644
index 00000000000..d9c1ec6cc23
--- /dev/null
+++ b/homeassistant/components/person/significant_change.py
@@ -0,0 +1,21 @@
+"""Helper to test significant Person state changes."""
+from typing import Any, Optional
+
+from homeassistant.core import HomeAssistant, callback
+
+
+@callback
+def async_check_significant_change(
+    hass: HomeAssistant,
+    old_state: str,
+    old_attrs: dict,
+    new_state: str,
+    new_attrs: dict,
+    **kwargs: Any,
+) -> Optional[bool]:
+    """Test if state significantly changed."""
+
+    if new_state != old_state:
+        return True
+
+    return False
diff --git a/tests/components/person/test_significant_change.py b/tests/components/person/test_significant_change.py
new file mode 100644
index 00000000000..1b4f6940e90
--- /dev/null
+++ b/tests/components/person/test_significant_change.py
@@ -0,0 +1,16 @@
+"""Test the Person significant change platform."""
+from homeassistant.components.person.significant_change import (
+    async_check_significant_change,
+)
+
+
+async def test_significant_change():
+    """Detect Person significant changes and ensure that attribute changes do not trigger a significant change."""
+    old_attrs = {"source": "device_tracker.wifi_device"}
+    new_attrs = {"source": "device_tracker.gps_device"}
+    assert not async_check_significant_change(
+        None, "home", old_attrs, "home", new_attrs
+    )
+    assert async_check_significant_change(
+        None, "home", new_attrs, "not_home", new_attrs
+    )